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16 - b it, 310 m s ps, 3. 3 v/1. 8 v dua l analog - to - digital converter (adc) d ata she et AD9652 f e a t u r es h ig h d y n am ic r an g e s nr = 7 5 .0 d b fs a t 70 m hz ( a i n = ? 1 d b fs) sfd r = 87 db c at 70 mh z ( a in = ? 1 d b fs) no ise sp ec t r a l d en sit y ( ns d ) = ? 15 6. 7 db f s / hz in p u t n o ise at ? 1 d b fs a t 7 0 m h z ns d = ? 157. 6 d b f s / h z f o r sm al l sig n al at ? 7 d b fs a t 7 0 m h z 9 0 db c h an n el i so l a t io n / c r o sst al k on - ch i p d it h er in g (im p r o v es sm al l sig n al l in e ar it y ) ex c el l en t i f sa mp l in g p er f o rman c e snr = 7 3. 7 d b fs a t 170 m hz (a in = ? 1 d b fs) sfd r = 85 db c at 170 m hz (a in = ? 1 d b fs) f u ll p o w e r b an d w id t h o f 46 5 m hz on - c h ip 3. 3 v b u ff er pr o g r am mab l e in p u t sp an o f 2 v p - p to 2 .5 v p - p (d efa u l t ) d iff er en t ia l c l o c k i n p ut r e ce iv er wi t h 1, 2 , 4 , a n d 8 in t eg er i n p ut s ( c l o c k di vi de r i n p ut ac c ep t s u p t o 1. 2 4 ghz) i n t er n al a d c c l o c k d u t y c y c l e st ab il iz er sy n c i n p u t a l l o w s mu l tic h ip sy n c h r o n iz a t io n to t al po w er c o n su mp t i o n : 2 .1 6 w 3. 3 v an d 1. 8 v s up p l y v o l t a g e s ddr l v ds ( an si - 644 l e v e ls ) o ut p ut s s er ial p or t c on t r ol en er g y sa v in g po w er - do w n m o de s a p p l ic a t io n s m il it ar y r a da r a n d c o mmu n i c a ti o n s m u l t im o d e d ig it al r ec eiv er s (3 g o r 4 g) t est an d i n s tru me n ta t io n smar t an t en n a sy st em s f u n c t i on a l b l oc k d i a g r am 12169-001 ddr dat a interleaver lvds output driver adc drv dd cs b av dd3 avdd spi sdio sclk p ro g ram m i ng dat a duty cy cl e s ta b ilize r di v i de 1 to 8 dco generation re f select multichip syn c sync agnd pdwn dco? dco+ d15 ( m s b) to d0 ( l s b) * or + , or ? cl k? clk+ vi n+ a vcm rbi as v i n?b vin+b v i n?a vr ef sen se a d 9652 adc 16 *t he s e p i ns are for channel a and channe l b. f i g u r e 1 . g e n e r a l d e s c r ip t i on th e a d 9652 is a d u a l , 16 - b it a nal o g - t o - d i g i t a l c o n v er t er ( ad c) w i t h s a m p li n g sp e e d s of up t o 310 m s ps . it is d e si g ne d t o s u p p o r t de ma ndi ng , h ig h s p e e d s ig n a l p r o c e s s in g a p p l ic a t io n s t h a t re q u i re ex c ep t i o n a l d y n a m i c r a n g e o v er a wi d e i n p u t f r e q u e nc y r ang e ( u p t o 4 6 5 mh z) . it s ex c ep t i o n a l l o w n o i s e f l o or of ? 15 7 .6 d bf s a n d la r g e si g n a l s p ur i o us - f r e e dy n am i c r ang e ( sf d r ) p e r f o r m anc e ( e x c eed i n g 85 d bf s , t y pi c a l ) a l lo w s l ow l e v el si g n a ls t o b e r e s o l ve d i n t he pr e s e n c e of l ar g e si g n a ls. t h e d u a l a d c c ore s f e at u r e a m u l t is t a g e , p i p e l in e d a r c h i t e c t u r e w i t h in t e g r a t e d ou t p u t e r r or c or r e c t i o n l o g i c . a h ig h p e r f o r manc e on - ch i p b u f fe r a n d i n t er n a l v o l t a g e r ef er en c e s i m p l if y t he i n t e r - f a c e t o e x t e r n a l d r i vi n g c i r c u i tr y w h i l e p r es e r vi n g t h e e xc e p t i on a l p e r f o r m anc e o f t h e ad c. th e a d 9652 c a n s up p o r t i n pu t c lo c k f r e qu e n c i e s of up t o 1. 24 g hz w it h a 1 , 2, 4 , a nd 8 i n t eg er c l o c k di v i de r u s e d t o g en er a t e t h e a d c s a m p le c lo c k . a d u ty c y c le s t a b i l i z er i s p r o vi d e d t o c o m p e n s a te f o r va r i a t i o n s i n t h e ad c c l o c k d u t y c y cl e . t he 16 - bi t o u t p u t d at a ( w i t h an o v e r r ang e b i t ) f rom e a ch ad c i s i n t e r l e a ve d o n t o a si n gl e l v d s o ut p ut p o r t a l o n g w i t h a d o u b l e d a t a r a t e ( ddr) cl o ck . p r o g r am m i ng f o r s e t u p and c o n t r o l ar e ac c o m p l i s he d u s i n g a 3 - wi r e sp i - c o m p a t i b l e s e r ia l in t e r f ac e . th e a d 9652 i s a v ai l ab l e i n a 14 4 - b a l l c sp _ b g a a nd i s s p e c i f i e d o v er t h e i n d u s t r i a l te m p er a t u r e r a n g e o f ? 40 c t o + 85 c. t his p r o d u c t i s p rot e c t e d by p e nd i ng u. s . p at e n t s. p r o d u c t h ighl igh t s 1. i n teg r a t e d d u a l , 16 - bi t , 310 ms p s ad c s. 2. on - c h i p b u f f e r s im p l if ie s a d c d r i v e r in t e r f ac e . 3. o p e r a t i o n f rom 3 .3 v a nd 1 .8 v s up p l i e s a nd a s e p ar a t e d i g i t a l o ut p ut d r i v e r su p p l y a c c o m m o d a t i n g l vd s o u t p u t s. 4. p r o p r ie t a r y d if f e r e n t ia l i n p u t m a in t ain s e x c e l l e n t si g na l - t o - n o is e r a t io ( sn r ) p e r f or m a n c e f or i n p u t f re q u e n c i e s of u p t o 485 m hz . 5. s yn c i n p u t a l l o w s s y n c h r o n i z a t i o n o f m u l t i p l e d e vi c es . 6. t h re e - w i re , 3 .3 v or 1 . 8 v sp i p or t f o r r e g is t e r p r o g r a m m in g a nd r e a d b ac k. r e v. a do c u m en t f eed b a c k in f o r m a t i o n f u r n i s h e d b y a n al o g d ev i c e s i s b el i ev e d t o b e ac c urat e a n d rel i ab l e . h o w ev e r , n o r es p o n s i b i l i t y i s a s s u m ed b y a n a l o g d e v i c e s f o r i t s us e , n o r f o r an y i n f ri n g e m en t s o f p a t en t s o r o t h e r r ig h t s o f th ir d pa r t ie s th a t m a y r e s u l t f r o m i ts u s e . s pe c i f ic a t io n s s u bj e c t t o c h a n g e w ith o u t n o ti c e . n o l i c en s e i s g r an t ed b y i m p l i c a t i o n o r o t h er wi s e un d e r an y p a t en t o r p a t en t r i g h t s o f a n a l o g d e v i c e s . t r a d e m a r k s a n d re g i s t ere d t r a d e m ar k s a re t h e p r o p e r t y o f t h ei r res p ec t i v e o w n er s . o n e t ech n o lo g y way, p . o . b o x 91 06, n o r w o o d , m a 020 62 - 910 6, u . s . a. t el: 781. 329. 4 700 ? 2014 a na l o g d e vic es, i nc . a l l r ig ht s r e se r ve d . t ec hnic al s u p p o r t w w w . an al og. c om http://
AD9652 data sheet t a bl e of co nt e nt s f e at u r e s ................................ ................................ .............................. 1 a p p l ic a t io n s ................................ ................................ ....................... 1 f u n c t io n a l b l o c k d ia g r am ................................ .............................. 1 g e n er a l d es c r i p t i o n ................................ ................................ ......... 1 p r o d u ct h i gh l i gh t s ................................ ................................ ........... 1 r e v is io n h i s t o r y ................................ ................................ ............... 2 s p e c if ic a t io n s ................................ ................................ ..................... 3 a d c d c s p e c if ic a t io n s ................................ ............................... 3 a d c a c s p e c if ic a t io n s ................................ ............................... 4 d ig i t a l s p e c if ic a t io n s ................................ ................................ ... 5 s w i t c hin g s p e c i f ic a t io n s ................................ .............................. 7 t im i n g s p e c if i c a t io n s ................................ ................................ .. 7 a bs o l u t e m ax i m u m r a t in g s ................................ ............................ 9 t he r m a l c ha r a c t e r is t ic s ................................ .............................. 9 e sd c a ut i o n ................................ ................................ .................. 9 p i n c o nf i g u r a t i o n a nd f u n c t i o n d e s c r i p t i o n s ........................... 10 t y p i c a l p e r f o r m anc e c h ar a c t e r i s t i c s ................................ ........... 13 e q u i va l e n t c i r c u i ts ................................ ................................ ......... 19 t h e or y of o p e r a t i on ................................ ................................ ...... 20 ad c a rc h i t e c t u re ................................ ................................ ...... 20 an a l o g i n p u t c o n s i d er a t i o n s ................................ .................... 20 v o l t a g e ref er en c e ................................ ................................ ....... 23 c l o c k i n p u t c o n s id e r a t io n s ................................ ...................... 23 p o w e r di s si p a t i o n a nd s t a ndb y m o de ................................ .... 25 i n t e r n a l b ac kg r o u n d c a l ib r a t io n ................................ ............. 25 di g i t a l o u t p u ts ................................ ................................ ........... 26 a d c o v e r r ang e ................................ ................................ .......... 26 f as t t hr e s h o l d d e t e c t io n ( f d a /f d b ) ................................ ........ 28 s er i a l p o r t i n t er f a c e ................................ ................................ ........ 29 c o n f ig u r a t io n u s in g t h e s p i ................................ ..................... 29 h ar dw ar e i n t e r f a c e ................................ ................................ ..... 29 co n f i g u r a t i o n w i t h o u t t h e s p i ................................ ................ 29 s p i a cce s s i b l e f e a t ur e s ................................ .............................. 30 m e m o r y m ap ................................ ................................ .................. 31 r e a d i ng t he m e mo r y m a p r e g i s t e r t ab l e ............................... 31 m em o r y m a p r eg i s t er t a b l e ................................ ..................... 32 a p p l ic a t io n s i n f o r m a t io n ................................ .............................. 35 d e sig n g u id e l i n e s ................................ ................................ ...... 35 o u t li ne d i me ns i o ns ................................ ................................ ....... 36 o r d e r in g g u id e ................................ ................................ .......... 36 r e v isio n hi s t or y 5/ 14 r e v . 0 t o r e v . a c h a n g es t o s u p p l y c u r r en t, c lo c k di vi d er = 1 p a r a m et er a n d po w e r c o n s u m p t i o n , c lo c k di vi d er = 1 p a r a m et er , t a b l e 1 ...... 3 4/ 14 r e v i s i on 0: i ni t i a l v e r si o n re v . a | p a ge 2 of 36
d ata she et ad 9652 sp ec ific a t io n s a dc dc s pe c i fi c a ti o n s av d d 3 = 3 .3 v , a vd d = a vd d _cl k = 1. 8 v , sp i v d d = dr v dd = 1 .8 v, sa m p l e r at e = 310 m sp s ( c l o c k i n p u t = 1240 mh z , a d 9652 di v i de d by 4 ) , v i n = ? 1 .0 d b f s d i f f e r e n t i a l i n p u t , 2. 5 v p - p f ul l - s c a l e i n p u t r ang e , d u ty c y c l e s t a b i l i z er ( d c s ) e n ab l e d, d it he r d i s ab l e d, unless otherwis e n o t e d . ta bl e 1 . p ar am e t er t em p er a t u r e m in ty p m ax un i t r e s ol u t i on fu l l 16 bits a c cur a cy n o m i s s i ng codes fu l l g u ar an t e e d o ff s e t er r o r fu l l 1.5 mv g ai n error fu l l ? 0.3 % fsr d if f er en t ia l n o n l in ea r it y ( d n l ) 1 fu l l ? 0.76/ +1 . 1 l sb i n t e g r al n onl i ne ar i t y ( i n l ) 1 fu l l ? 4.5/ + 4.5 l sb m a t c hin g c h a r a c t e r is t ic o ff s e t er r o r fu l l 0. 7 mv g ai n e r r or fu l l 0.1 % fsr t em pe r a t u r e dr if t o ff s e t er r o r fu l l 0.8 p p m / c g ai n e r r or fu ll 16 p p m / c in pu t r ef er r e d n o is e v re f = 1.25 v 25 c 3.7 lsb rms anal o g inpu t i npu t s pan ( fo r v re f = 1.25 v ) fu l l 2.5 v p -p i npu t c apac i t anc e 2 fu l l 5.8 pf i npu t r e s i s t anc e 3 fu l l 27 k? i npu t c om m on - m od e v ol t ag e fu l l 2.0 2.4 v p o wer s u pplie s s u p pl y v ol t ag e av d d 3 fu l l 3.15 3.3 3.45 v av d d fu l l 1.7 1.8 1.9 v avdd _cl k full 1.7 1.8 1.9 v dr v dd fu l l 1.7 1.8 1.9 v s piv dd fu l l 1.7 1.8 3.6 v s up p l y c ur r e n t , c l o ck d ivid er = 1 i av d d 3 fu l l 145 ma i avdd full 701 m a i a vd d _ cl k full 56 ma i dr v dd fu l l 180 ma i sp i vd d fu l l 0.005 ma po wer c o n s u m pt io n c l o ck d ivi d er = 1 n or m al o pe r a t i o n 1 fu l l 2160 2236 mw stan d by p ow e r 4 fu l l 80 mw po w e r - d o w n p ow e r fu l l 1 mw 1 m e a s ure d w i t h a l o w i n p ut f re q ue n cy, f ul l - s ca l e s i n e w a v e. 2 i np u t c a p a ci ta nc e r e f e r s to the e f f e cti v e c a p a ci ta nc e b e tw e e n o ne d i f f e r e nti a l i np u t pi n a nd a g nd . 3 i np u t r e s i s ta nc e r e f e r s to the e f f e cti v e r e s i s ta nc e b e tw e e n o ne d i f f e r e nti a l i np u t pi n a nd a g nd . 4 s t an d b y p o w e r is me as u r e d w it h a d c in p u t a nd the c lk p in s in ac t iv e ( tha t i s , s e t t o a v dd o r a g nd) . rev. a | page 3 of 36
AD9652 data sheet a d c a c s p e c if ic a t i on s av d d 3 = 3. 3 v , a vd d = a v d d _c l k = 1 .8 v , sp i v d d = dr v dd = 1 .8 v, sa m p l e r at e = 310 ms p s ( c l o c k i n p u t = 1240 mh z , a d 9652 di v i de d by 4 ) , v i n = ? 1 .0 d b f s d i f f e r e n t i a l i n p u t , 2 .5 v p - p f ul l - s c a le i n p u t r a n ge , d c s e n a b l e d, d i t he r d i s ab l e d, u n l es s o t h er w i s e n o t e d . table 2 . v r ef = 1 v v r ef = 1.2 5 v , d ef au lt p aram et er 1 t em p er at u re mi n t yp ma x mi n t yp ma x unit d i f f er en t i al i n p u t v ol t ag e 25 c 2 .0 2 .5 v p - p s i g na l - to - n oi s e r at i o ( s nr ) f in = 3 0 m h z (u se n y q uist 1 s e t t in g s) 25 c 74. 0 75. 4 db fs f in = 7 0 m h z (u se n y q uist 1 s e t t in g s) 25 c 73. 6 74. 0 75. 0 db fs f ul l 73. 3 db fs f in = 70 m h z ( us e n yq u i s t 1 s e t t i ng s , w i t h d i t he r en a bl e d ) 25 c 73. 1 74. 3 db fs f in = 170 m h z ( u se n y q uist 2 s e t t i n g s) 25 c 72. 1 73. 7 db fs f in = 170 mhz (use nyquist 2 settings, with dither enabled) 25c 71.2 72.0 dbfs f in = 305 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c 70. 1 70. 7 db fs f in = 400 m h z ( us e n yq u i s t 3 s e t t i ng s ) 25 c 67. 9 68 .0 db fs sig n a l - to - n oi s e an d d i s t or t i on ( s i n ad ) f in = 3 0 m h z (u se n y q uist 1 s e t t in g s) 25 c 72. 8 74. 2 db fs f in = 7 0 m h z (u se n y q uist 1 s e t t in g s) 25 c 73. 5 73. 8 74. 6 db fs f ul l 73. 2 db fs f in = 7 0 m h z (u se n y q uist 1 s e t t in g s, w it h d it h er e n a b l ed) 25 c 73. 0 74. 0 db fs f in = 170 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c 72. 0 72. 6 db fs f in = 170 mhz (use nyquist 2 settings, with dither enabled) 25c 71.1 71.7 dbfs f in = 305 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c 68. 5 db fs f in = 400 m h z ( u se n y q uist 3 s e t t i n g s) 25 c 65. 8 db fs ef f ec t i v e n um b er of b i t s ( en o b ) f in = 3 0 m h z (u se n y q uist 1 s e t t in g s) 25 c 11. 8 12. 0 bi ts f in = 7 0 m h z (u se n y q uist 1 s e t t in g s) 25 c 12 12. 0 12. 1 bi ts f ul l 11. 9 bi ts f in = 70 m h z ( u se n y q uist 1 s e t t in g s, w it h d it h e r e n a b l e d ) 25 c 11. 8 12. 0 bi ts f in = 170 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c 11. 7 11. 8 bi ts f in = 170 mhz (use nyquist 2 settings, with dither enabled) 25c 11.5 11.6 bits f in = 305 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c 11. 1 bi ts f in = 400 m h z ( us e n yq u i s t 3 s e t t i ng s ) 25 c 10. 6 bi ts w o rs t s e co nd o r t h i rd ha rm o ni c f in = 30 mhz (use nyquist 1 settings) 25 c ? 96 ? 94 db c f in = 7 0 m h z (u se n y q uist 1 s e t t in g s) 25 c ? 90 ? 87 ? 83 db c f ul l ? 83 db c f in = 70 m h z ( us e n yq u i s t 1 s e t t i ng s , w i t h d i t he r en a bl e d ) 25 c ? 92 ? 89 db c f in = 170 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c ? 87 ? 85 db c f in = 170 m h z ( us e n yq u i s t 2 s e t t i ng s , w i t h d i t he r ena bl e d ) 25 c ? 87 ? 85 db c f in = 305 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c ? 89 ? 86 db c f in = 400 m h z ( us e n yq u i s t 3 s e t t i ng s ) 25 c ? 80 ? 77 db c sp u r io u s- f r ee d yn am i c r an g e ( s f d r ) f in = 30 mhz (use nyqui st 1 settings) 25c 96 94 db c f in = 7 0 m h z (u se n y q uist 1 s e t t in g s) 25 c 90 83 87 db c f ul l 83 db c f in = 70 m h z ( us e n yq u i s t 1 s e t t i ng s . w i t h d i t he r en a bl e d ) 25 c 92 89 db c f in = 170 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c 84 85 db c f in = 170 m h z ( us e n yq u i s t 2 s e t t i ng s , w i t h d i t he r ena bl e d ) 25 c 87 85 db c f in = 305 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c 89 86 db c f in = 400 m h z ( us e n yq u i s t 3 s e t t i ng s ) 25 c 80 77 db c re v. a | page 4 of 36
d ata she et ad 9652 v r ef = 1 v v r ef = 1.2 5 v , d ef au lt p aram et er 1 t em p er at u re mi n t yp ma x mi n t yp ma x unit w o rs t o t h e r ( no t i ncl u d i ng 2 nd o r 3 rd h a rm o ni c) f in = 3 0 m h z (u se n y q uist 1 s e t t in g s) 25 c ? 1 01 ? 1 02 db c f in = 7 0 m h z (u se n y q uist 1 s e t t in g s) 25 c ? 99 ? 98 ? 90 db c full ?86 dbc f in = 70 m h z ( us e n yq u i s t 1 s e t t i ng s , w i t h d i t he r en a bl e d ) 25 c ? 1 00 ? 1 00 db c f in = 170 m h z ( us e n yq u i s t 2 s e t t in g s ) 25 c ? 91 ? 90 db c f in = 170 m h z ( us e n yq u i s t 2 s e t t i ng s , w i t h d i t he r ena bl e d ) 25 c ? 90 ? 95 db c f in = 305 m h z ( us e n yq u i s t 2 s e t t i ng s ) 25 c ? 98 ? 97 db c f in = 400 m h z ( us e n yq u i s t 3 s e t t i ng s ) 25 c ? 92 ? 91 db c t wo - t o ne s f d r f in = 70. 1 m h z ( ? 7 d b f s ) , 72. 1 m h z ( ? 7 d b f s ) 25 c 93 db c f in = 184. 1 2 m h z ( ? 7 d b f s ) , 18 7. 12 m h z ( ? 7 d b f s ) 25 c 83 db c c r o sst a l k 2 f ul l 90 90 db f u ll p o w e r ba n d w id t h 3 25 c 485 485 mh z n o ise ba n d w i d t h 4 25 c 650 650 mh z 1 se e the an - 8 3 5 a p p l ic at io n no t e , un d er st a n d in g h ig h s pe ed a d c t e st in g a n d e v a lu a t io n , fo r a c o m p le t e se t o f de fi n i t i o n s. 2 cr o s st a lk i s m e a s u r e d a t 1 0 0 mh z w i t h ?1 . 0 db f s o n o ne c ha nne l a nd no i np u t o n the a l te r na te c ha nne l . 3 f u l l po we r b a nd wi d th i s the b a nd wi d t h o f o p e r a ti o n i n w hi ch pr o p e r a d c pe r f o r m a nc e c a n be a chi e v e d . 4 n o i s e b a nd wi d th i s the ? 3 d b b a nd wi d th f o r the a d c i np u ts a cr o s s w hi ch no i s e c a n e nte r the ad c a nd i s no t a tte nu a ted i nte r na l l y . d igi t a l s p e c if ic a t i on s av d d 3 = 3 .3 v , a vd d = a v d d _c l k = 1 .8 v , sp i v d d = dr v dd = 1 .8 v, sa m p l e r at e = 310 ms p s (c l o c k i n p u t = 1240 mh z , a d 9652 di v i de d by 4 ) , v i n = ? 1 .0 d b f s d i f f e r e n t i a l i n p u t , 2 .5 v p - p f ul l - s c a le i n p u t r a n ge , d c s e n a b le d, d i t he r d i s ab le d, u n l es s o t h er w i s e n o t e d . ta bl e 3. p ar am e t er t est c o n d it io n s/ c o mmen t s te mp e ra t u r e m in ty p m ax un i t differential clock inputs (clk+, clk?) logic compliance cmos/lvds/lvp ecl differ e n t i a l i npu t v ol t ag e fu l l 0.3 3.6 v p - p input voltage range fu l l ag n d av d d _cl k v i n t ernal common - m od e bi as fu l l 0.9 v i npu t c om m on - mode range fu l l 0.9 1.4 v h ig h l ev el i n p u t c u r r en t full +10 + 145 a l o w l ev el i n p u t c u r r en t fu l l ? 155 ?1 5 a input c apac i t anc e 1 fu l l 5 pf i npu t r e s i s t anc e 1 fu l l 10 k? sy n c i n put l o g ic c o mp l ia n c e cm o s/ l v d s i n t e r nal bi as fu l l 0.9 v i npu t v ol t ag e r ang e fu l l ag n d av d d _cl k v hi g h l e v e l i npu t v ol t ag e fu l l 1.2 av d d _cl k v lo w l e v e l i npu t v ol t ag e fu l l ag n d 0.6 v h ig h l ev el i n p u t c u r r en t fu l l ? 15 + 110 a l o w l ev el i n p u t c u r r en t fu l l ? 105 + 15 a i npu t c apac i t anc e fu l l 1.5 pf i npu t r e s i s t anc e fu l l 16 k? re v . a | p a ge 5 of 36
AD9652 data sheet p ar am e t er t est c o n d it io n s/ c o m m en t s te m p e ra t u r e m in ty p m ax unit l o gic in pu t ( cs b ) 2 h i g h l e v e l i npu t v ol t ag e fu l l 1.22 s piv dd v l o w l e v e l i npu t v ol t ag e fu l l 0 0.6 v h ig h l ev el i n p u t c u r r en t fu l l ? 65 + 65 a l o w l ev el i n p u t c u r r en t full ? 135 0 a i npu t r e s i s t anc e fu l l 26 k ? i npu t c apac i t anc e fu l l 2 pf l o gic in pu t ( s c lk ) 3 h i g h level inpu t v ol t ag e fu l l 1.22 s piv dd v l o w l e v e l i npu t v ol t ag e fu l l 0 0.6 v h ig h l ev el i n p u t c u r r en t fu l l 0 110 a l o w l ev el i n p u t c u r r en t fu l l ? 60 +5 0 a i npu t r e s i s t anc e fu l l 26 k ? i npu t c apac i t anc e fu l l 2 pf l o gic in pu t s ( s dio ) 2 h i g h l e v e l i npu t voltage fu l l 1.22 s piv dd v l o w l e v e l i npu t v ol t ag e fu l l 0 0.6 v h ig h l ev el i n p u t c u r r en t fu l l ?6 5 + 70 a l o w l ev el i n p u t c u r r en t fu l l ? 135 0 a i npu t r e s i s t anc e fu l l 26 k ? i npu t c apac i t anc e fu l l 5 pf l o gic in pu t s ( pdwn ) 3 h i g h l e v e l i npu t v ol t ag e fu l l 1.22 dr v dd v l o w l e v e l i npu t v ol t ag e fu l l 0 0.6 v h ig h l ev el i n p u t c u r r en t fu l l ? 80 + 190 a l o w l ev el i n p u t c u r r en t fu ll ? 145 + 130 a i npu t r e s i s t anc e fu l l 26 k ? i npu t c apac i t anc e fu l l 5 pf digit a l o u t pu t s l v d s d a t a and or o utp uts a ssu m e s n o m i n a l 1 0 0 ? d if f er en t ia l t er m in a t io n ansi mode d i f f e r e n ti a l o utp ut voltage ( v od ) m a x imu m s et t in g , d ef a u lt fu l l 310 350 450 mv o utp ut o f f s e t v o l ta g e ( v os ) fu l l 1.15 1.22 1.35 v r ed u ced swing mode d i f f e r e n ti a l o utp ut v o l ta g e ( v od ) m in imu m s et t in g fu l l 150 200 280 mv o utp ut o f f s e t v o l ta g e ( v os ) fu l l 1.15 1.22 1.35 v 1 i np u t c a p a c i ta nc e / r e s i s ta nc e r e f e r s to the e f f e c ti v e c a p a ci ta nc e / r e s i s ta nc e b e tw e e n o ne d i f f e r e nti a l i np u t pi n a nd a g n d . 2 i nte r na l w e a k p u ll- u p. 3 i nte r na l w e a k p u ll- d o wn. re v . a | p a ge 6 of 36
data sheet AD9652 r e v. a | pa ge 7 o f 3 6 switchi n g specificati o ns table 4. p a r a me t e r t e st c o ndition s /c ommen ts t e mper a tur e m i n t y p ma x unit cl o c k input p ar a me te rs ( c l k ) i n put clock r a te f u ll 80 1240 mh z co nve r s i o n r a t e 1 f u ll 80 310 msps p e r i o d div ide - b y -1 m o de (t cl k ) f u ll 3.2 ns p u lse w i dth h i gh ( t ch ), m i nimum divide -b y-1 m o de dcs enabled f u ll 0.8 ns d c s d i s a b l e d f u ll 1.3 ns divide -b y - 2 m o de t h r o ugh divide -b y - 8 m o de f u l l 0.8 ns aper tur e dela y ( t a ) f u ll 1.0 ns aper tur e unc e r t ain t y ( j itt e r , t j ) f u ll 0.1 ps r ms d a t a o u tpu t p a r a me te rs lv d s m o d e da ta p r opag a tion dela y (t pd ) f u ll 290 ps dc o p r opag a tion d e la y (t dc o ) f u ll 290 ps dc o-to -d a ta skew (t sk e w ) f u ll 0 ns pi p e li n e d e lay ( l ate n c y ) fu l l 2 6 c y c l e s w a ke -up t ime f r om standb y f u ll 100 s f r o m p o w e r - d o w n f u ll 1 sec o u t- of-r ange rec o v er y t ime f u ll 3 c y c l e s 1 con v er si on ra t e i s t h e cloc k ra t e a f t er t h e di vi der . timing spe cific ations table 5. p a r a me t e r t e st c o ndition s /c ommen ts m i n t y p ma x unit sy nc ti ming requireme n t s t ssyn c sy nc t o the risi ng edge of clk + setup time 0.1 ns t hsy n c sy nc t o the risi ng edge of clk + hold time 0.1 ns spi ti ming req u ireme nt s t ds setup time bet w een the da ta and th e rising ed ge of sclk 2 ns t dh hold time bet w een the da ta and the rising edg e of sclk 2 ns t clk p e r i od of the sc lk 40 ns t s s e tup time bet w een csb and sclk 2 ns t h hold time bet w een csb and sclk 2 ns t high m inimum per iod tha t sclk is in a logic high st a t e 10 ns t lo w m inimum per iod tha t sclk is in a logic low sta t e 10 ns t en_sdio t ime r e q u ir ed f o r the sdio pin to swit c h fr om an input t o an output r e la tiv e t o the sclk falling edge (not sho w n in t iming diagr a ms) 10 ns t dis_sdio t ime r e q u ir ed f o r the sdio pin t o swit c h fr om an output t o an i n put r e la tiv e t o the sclk r ising edge (not sho w n in t iming diagr a ms) 10 ns t spi_rst t ime r equir ed af ter po w e r-up , h a r d or sof t r eset un til spi ac c ess i s a v ai lab l e ( n ot sho w n in t imin g diagr a ms) 500 s
AD9652 data sheet ti ming diagrams t pd t skew t ch t dco t clk n ? 1 n + 1 n + 2 n + 3 n + 5 n + 4 n v i n x clk+ clk? dco ? dco + t a paral l e l i n t er l ea ved channe l a and channe l b ch a n ? 26 ch b n ? 26 ch a n ? 25 ch b n ? 25 ch a n ? 24 ch b n ? 24 ch a n ? 23 ch b n ? 23 ch a n ? 22 d0 ( l s b) ch a n ? 26 ch b n ? 26 ch a n ? 25 ch b n ? 25 ch a n ? 24 ch b n ? 24 ch a n ? 23 ch b n ? 23 ch a n ? 22 d15 ( m s b) 12169-002 fi g u r e 2 . l v ds d at a o u t p u t t im in g t ssyn c t hsync sync cl k 12169-003 fi g u r e 3 . sy nc t i m i ng inp ut s do n? t care do n? t care do n? t care do n? t care s di o s cl k cs b t s t dh t cl k t ds t h r/w w1 w0 a12 a11 a10 a9 a8 a7 d5 d4 d3 d2 d1 d0 t lo w t h igh 12169-049 fi g u r e 4 . s e r i al p or t i n t e r f a c e t i m i n g d iag r a m re v . a | p a ge 8 of 36
data sheet AD9652 r e v. a | pa ge 9 o f 3 6 absolute maximum ra tings table 6. p a r a me t e r r a ting electrical avdd3 to agnd ?0.3 v to +3.6 v avdd_clk to agnd ?0.3 v to +2.0 v avdd to agnd ?0.3 v to +2.0 v drvdd to agnd ?0.3 v to +2.0 v spivdd to agnd ?0.3 v to +3.6 v vin+a/vin+b, vin?a/vin?b to agnd 1.2 v to 3.0 v clk+, clk? to a g nd ?0.3 v t o a v d d _ clk + 0.2 v sync to agnd ?0.3 v to avdd_clk + 0.2 v vcm to agnd ?0.3 v to avdd + 0.2 v csb to agnd ?0.3 v to spivdd + 0.3 v sclk to agnd ?0.3 v to spivdd + 0.3 v sdio to agnd ?0.3 v to spivdd + 0.3 v pdwn to agnd ?0.3 v to drvdd + 0.3 v or+/or? to agnd ?0.3 v to drvdd + 0.3 v d0 through d15 to agnd ?0.3 v to drvdd + 0.3 v dco to agnd ?0.3 v to drvdd + 0.3 v environmental o p er a t in g t e mp er a tur e r a nge (a m b ie nt ) ?40c to +85c m a ximum junc tion t e mpera tur e under bias 125c stor age t empera tur e r a nge ( a mbien t ) ?65c to +150c s t r e s s es a t o r ab o v e t h os e lis t e d un der a b s o l u t e m a xi m um r a t i n g s ma y c a us e p e r m an en t da ma g e t o t h e pr o d uc t. this is a s t r e s s ra t i ng o n ly ; f u n c t i o n al op era t io n o f t h e p r o d uc t a t t h es e o r a n y o t h e r condi t i on s ab o v e t h o s e indi ca te d i n t h e o p er a t io n a l s e c t io n o f t his sp e c if ic a t io n is no t im pl ie d . o p e r a t io n b e yon d t h e maxi m u m op era t i n g con d i t i o n s fo r ext en d e d p er i o d s ma y af fe c t pro d u c t rel i abi l it y . thermal c h aracteristics ty p i c a l ja is sp e c if ie d fo r b o t h a 4-l a yer p r in t e d cir c ui t b o a r d (pcb) wi t h a s o lid g r o u nd plane f r o m t h e jedec 51-2 a nd an 8-l a yer pcb . the 8-l a yer pcb has 2 oz co p p er l a yers (m1 a n d m8), 1 oz co p p e r inn er la yers, and v i as connec t in g to l a yers m2, m5, a nd m7. a s sho w n in t a b le 7, a i r f lo w incr e a s e s h e a t dissi p a tio n , which re d u c e s ja . i n ad di ti o n , m e tal in di r e ct co n t a c t w i th t h e pa c k a g e lead s f r o m m e tal tra c es, th r o ugh h o le s, gr o u n d , a n d p o w er plan es, re d u ces t h e ja . table 7. therm a l resistance pa c k a g e t y p e ai r f l o w ve l o c i t y (m/sec) b o a r d t y p e ja 2 unit 144-b a ll c s p _ bg a 10 mm 1 0 m m (b c-1 44- 6) 0 8-la y e r pcb 15.8 c/w 1.0 8-la y e r pcb 13.9 c/w 0 jedec 1 21.7 c/w 1.0 jedec 1 19.2 c/w 1 p e r je dec jesd51-7, pl us je dec 25-5 2s2p test board. 2 p e r je d e c je sd51-2 ( s t ill air) or je dec je sd51-6 ( m oving air) . esd caution
AD9652 data sheet rev. a | page 10 of 36 pin conf igura tion and fu nction descriptions a b c d e f g j h k l m 1 2 3 5 6 7 10 11 12 48 9 rb i a s v cm avdd 3 v i n ? b a v d d 3 a v d d3 a v d d 3 s e n se v r e f vi n+ b v i n ? a vi n+ a a g nd av dd 3 a v d d3 a g nd av dd 3 av dd 3 av dd 3 av dd 3 ag n d a g nd a g nd ag nd ag n d ag n d avdd ag n d av dd _ clk av dd _ cl k av dd a g nd ag n d a g nd a g nd ag nd clk ? ag n d avdd ag n d av dd _ clk av dd _ cl k av dd a g nd cs b a g nd a g nd ag nd clk + ag n d avdd ag n d av dd _ clk av dd _ cl k av dd a g nd s d i o a g nd a g nd ag nd t est ag n d avdd ag n d av dd _ clk av dd _ cl k av dd a g nd s c l k a g nd a g nd ag nd sy n c ag n d avdd ag n d avd d avdd a v d d ag n d o r + a g nd a g nd ag nd pd w n ag n d avdd ag n d avd d avdd a v d d ag n d o r ? a g nd a g nd ag nd d 0 ? d 0 + drg nd d rg n d dr g nd dr g nd dr g nd d1 5 + d 1 5 ? d rg n d d c0 + d rg n d d 1 ? d 1 + dr v d d spi v d d d rvdd dr vdd d rvdd d1 4 + d 1 4 ? dr v d d d c 0 ? drvd d d 2+ d 3+ d 4+ d 6+ d 7+ d 8+ d 11+ d 12+ d 13+ d 5+ d 9+ d 10+ d 2? d 3? d 4? d 6? d 7? d 8? d 11? d 12? d 13? d 5? d 9? d 10? a d9652 t o p vi ew ( n o t t o s cal e) 12169-004 figure 5. pin c o nfiguration ta ble 8. pi n f u nct i on d es c ri pt i o ns p i n no . m n emonic t y pe description adc p o w e r sup p lies k5 spivdd supply serial interface logic volt age supply (1.8 v typical, 3.3 v optional) k3, k4, k6, k7, k9, k10 drvdd supply digita l output driver supply (1.8 v nominal). a3, a6, a7, a10, b2, b3, b6, b7, b10, b11 avdd3 supply 3.3 v analog power supply (3.3 v nominal). c6, c7, d6, d7, e6, e7, f6, f7 avdd_clk supply 1.8 v analog power supply for clock circuitry (1.8 v nominal). c3, c10, d3, d1 0, e3, e10, f3, f10, g3, g6, g7, g10, h3, h6, h7, h10 avdd supply 1.8 v analog power supply (1.8 v nominal). b1, b4, b5, b8, b9, b12, c1, c2, c4, c5, c8, c9, c 11, c12, d2, d4, d5, d8, d9, d11, e2, e4, e5, e8, e9, e1 1, f 2, f4, f5, f8, f9, f11, g2, g4, g5, g8, g9, g11, h2, h4, h5, h8, h9, h11 ag n d analog gr ound analog ground reference for avdd3, avdd_clk, and avdd.
data sheet AD9652 rev. a | page 11 of 36 p i n no . m n emonic t y pe description j3 drgnd digital ground digital and output driver ground reference. j4 drgnd digital ground digital and output driver ground reference. j5 drgnd digital ground digital and output driver ground reference. j6 drgnd digital ground digital and output driver ground reference. j7 drgnd digital ground digital and output driver ground reference. j9 drgnd digital ground digital and output driver ground reference. j10 drgnd digital ground digital and output driver ground reference. adc analog a9 vin+a input differential analog input pin (+) for channel a. a8 vin?a input differential analog input pin (?) for channel a. a4 vin+b input differential analog input pin (+) for channel b. a5 vin?b input differential analog input pin (?) for channel b. a2 vcm output common-mode level bias output for analog inputs. decouple this pin to ground using a 0.1 f capacitor. a1 rbias o utput ex t e rnal bias r e sist er c o nnec t ion. a 10 k r e sister must be c o nnec t ed bet w een this pin a n d analog gr ound ( a gnd). a12 vref input/output voltage reference input/output. a11 sense input reference mode selection (see table 12). e1 clk+ input adc clock input (true). d1 clk? input adc clock input (complement). dig ital i n puts f1 test input pull-down. unused digital input, pull to ground through a 50 resistor. g1 sync input digital input clock synchronization pin. tie low if unused. h1 p d w n in p u t p o w e r-d o wn i n put ( a c t iv e h igh ). the opera tion of this pin depends on the spi mode and c a n be c o nfigur e d as po w e r- do w n or standby (see register 0x08 in table 17). dig i tal o utputs j2 d0+ output channel a/channel b lvds output data 0 (true, lsb). j1 d0? output channel a/channel b lvds output data 0 (complement, lsb). k2 d1+ output channel a/channel b lvds output data 1 (true). k1 d1? output channel a/channel b lvds output data 1 (complement). l1 d2+ output channel a/channel b lvds output data 2 (true). m1 d2? output channel a/channel b lvds output data 2 (complement). l2 d3+ output channel a/channel b lvds output data 3 (true). m2 d3? output channel a/channel b lvds output data 3 (complement). l3 d4+ output channel a/channel b lvds output data 4 (true). m3 d4? output channel a/channel b lvds output data 4 (complement). l4 d5+ output channel a/channel b lvds output data 5 (true). m4 d5? output channel a/channel b lvds output data 5 (complement). l5 d6+ output channel a/channel b lvds output data 6 (true). m5 d6? output channel a/channel b lvds output data 6 (complement). l6 d7+ output channel a/channel b lvds output data 7 (true). m6 d7? output channel a/channel b lvds output data 7 (complement). l7 d8+ output channel a/channel b lvds output data 8 (true). m7 d8? output channel a/channel b lvds output data 8 (complement). l8 d9+ output channel a/channel b lvds output data 9 (true). m8 d9? output channel a/channel b lvds output data 9 (complement). l9 d10+ output channel a/channel b lvds output data 10 (true). m9 d10? output channel a/channel b lvds output data 10 (complement). l10 d11+ output channel a/channel b lvds output data 11 (true). m10 d11? output channel a/channel b lvds output data 11 (complement). l11 d12+ output channel a/channel b lvds output data 12 (true). m11 d12? output channel a/channel b lvds output data 12 (complement).
AD9652 data sheet rev. a | page 12 of 36 p i n no . m n emonic t y pe description l12 d13+ o utput channel a/channel b lvds output data 13 (true). m12 d13? o utput channel a/channel b lvds output data 13 (complement). k11 d14+ o utput channel a/channel b lvds output data 14 (true). k12 d14? o utput channel a/channel b lvds output data 14 (complement). j 11 d15+ o utput channel a/channel b lvds output data 15 (true, msb). j12 d15? o utput channel a/channel b lvds output data 15 (complement, msb). g12 or+ o utput channel a/channel b lvds overrange (true). h12 or? o utput channel a/channel b lvds overrange (complement). j 8 dc o+ o utput channel a/channel b lvds data clock output (true). k8 dc o? o utput channel a/channel b lvds data clock output (complement). spi c o n tr o l f12 sclk i n put spi serial clock. e12 sdio i n put/ o utput spi serial data input/output. d12 csb i n put spi chip s elec t ( a c t iv e l o w) . this pin must be p u lled high a t power-up.
d ata she et ad 9652 t y pi ca l pe rf orm a nce c ha ra ct e ri s t i cs avdd 3 = 3.3 v, avdd = avdd_cl k = 1.8 v , spivdd = drvdd = 1.8 v, sa mple r ate = 310 msps (c lock input = 1240 mhz, AD9652 divide by 4) , vin = ?1.0 dbfs differential, v ref = 1.25 v , dcs enabled, dither disabled, unless otherwise noted. 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 140 120 100 80 60 40 20 am p l i t ude ( d b) f in (mh z) a in = ?1d bf s s nrf s = 75. 0d b s f dr = 89d bc 12169-005 f i g u r e 6 . si ng l e to ne f a st f ou r ie r t r a n sfo r m ( fft ) w it h f in = 7 0. 1 m h z ( nsd = ? 1 5 6 . 7 d bf s/ h z ) 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 140 120 100 80 60 40 20 am p l i t ude ( d b) f in (mh z) a in = ?7dbfs snrfs = 75.7db sfdr = 91.9dbc 12169-007 f i g u r e 7 . si ng l e to ne f f t wi t h f in = 70 . 1 m hz at ? 7 d b f s ( nsd = ? 1 5 7 . 6 d bf s/ h z ) 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 140 120 100 80 60 40 20 am p l i t ude ( d b) f in (mh z) a in = ?1dbfs snrfs = 73.2db sfdr = 88dbc 12169-009 f i g u r e 8 . si ng l e to ne f f t wi t h f in = 18 5 m h z . at ? 1 d b f s ( nsd = ? 15 5. 2 d b f s /h z ) , re g i ste r 0 x 2 2 a = 0 x0 1 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 140 120 100 80 60 40 20 am p l i t ude ( d b) f in (mh z) a in = ?1dbfs snrfs = 74.4db sfdr = 90dbc 12169-006 f i g u r e 9 . si ng l e to ne f f t wi t h f in = 70 . 1 m hz w it h d it h e r ( nsd = ? 1 5 6 . 3 d bf s/ h z ) 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 140 120 100 80 60 40 20 am p l i t ude ( d b) f in (mh z) a in = ?7dbfs snrfs = 75.2db sfdr = 94.4dbc 12169-008 f i g u r e 10 . s i ng l e t o ne f f t w i t h f in = 7 0 .1 m h z a t ? 7 d bf s wi t h d i t he r ( nsd = ? 1 5 7 . 1 d bf s/ h z ) 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 140 120 100 80 60 40 20 am p l i t ude ( d b) f in (mh z) a in = ?1dbfs snrfs = 72.9db sfdr = 88dbc 12169-010 f i g u r e 11 . s i ng l e t o ne f f t w i t h f in = 1 85 m hz at ? 1 d b f s w i t h d it h e r ( nsd = ? 15 4. 9 d b f s /h z ) , re g i ste r 0 x 2 2 a = 0 x0 1 rev. a | page 13 of 36
AD9652 data sheet 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 140 120 100 80 60 40 20 am p l i t ude ( d b) f in (mh z) a in = ?7d bf s s nrf s = 75d b sfdr = 92dbc 12169-0 1 1 figure 12 . single tone fft with f in = 185 mhz at ?7 dbfs ( nsd = ?156.9 dbfs/hz) , register 0x22a = 0x01 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 50 100 150 12169- 200 m ag ni t ude ( d b) f in (mh z) a in = ?1dbfs snrfs = 69.7db sfdr = 86.9dbc f i g u r e 13 . fft f in = 30 5 m hz , a in = ?1 d b f s , d i t h er o f f , r e g is t e r 0x 22a = 0x 0 1 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 50 100 150 12169- 204 m ag ni t ude ( d b) f in (mh z) a in = ?7dbfs snrfs = 72.7db sfdr = 90.7dbc figure 14 . fft f in = 305 mhz, a in = ?7 dbfs, dither off , register 0x22a = 0x01 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 140 120 100 80 60 40 20 am p l i t ude ( d b) f in (mh z) a in = ?7d bf s s nrf s = 74. 5d b sfdr = 93dbc 12169-012 figure 15 . single tone fft with f in = 185 mhz at ?7db fs with dither (nsd = ?156.4 dbfs/hz) , register 0x22a = 0x01 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 50 100 150 12169- 201 m ag ni t ude ( d b) f in (mh z) a in = ?1dbfs snrfs = 69.5db sfdr = 91.6dbc figure 16 . fft f in = 305 mhz, a in = ?1 dbfs, dither on , register 0x22a = 0x01 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 50 100 150 12169- 205 m ag ni t ude ( d b) f in (mh z) a in = ?7dbfs snrfs = 72.8db sfdr = 90.7dbc f i g u r e 17 . fft f in = 30 5 m hz , a in = ?7 d b f s , d i t h er o n , re g is t e r 0x 22a = 0x 0 1 rev. a | page 14 of 36
d ata she et ad 9652 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 50 100 150 12169- 202 m ag ni t ude ( d b) f in (mh z) a in = ?1d bf s s nrf s = 68. 0d b sfdr = 75.7dbc f i g u r e 18 . fft f in = 40 0 m hz , a in = ?1 d b f s , d i t h er o f f , r e g is t e r 0x 22a = 0x 0 2 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 50 100 150 12169- 206 m ag ni t ude ( d b) f in (mh z) a in = ?7d bf s s nrf s = 71. 7d b sfdr = 81.3dbc figure 19 . fft f in = 400 mhz, a in = ?7 dbfs, dither off , register 0x22a = 0x02 140 20 78 60 62 64 66 68 70 72 74 76 40 60 80 100 120 ?80 ?60 ?40 ?20 0 12169- 014 s nr ( d b) s f dr ( d b) a in ( ?dbfs ) sf d r ( d b c) , ?40 c s fdr (dbc), +25c s fdr (dbc), +85c sf dr ( d bf s ) , ? 4 0 c s fdr (dbfs), +25c sfdr (dbfs), +85c snrf s ( d b) , ? 4 0 c s nrf s ( d b) , + 2 5 c s nrfs (db), +85c f i g u r e 20 . s i ng l e t o ne sn r / sf dr v s . i np ut a m p l i t ud e ( a in ) w i t h f in = 9 0. 1 m hz , v re f = 1 . 2 5 v , o v e r t em p era t u re, d i t h er o f f 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 50 100 150 12169- 203 m ag ni t ude ( d b) f in (mh z) a in = ?1d bf s s nrf s = 68. 0d b sfdr = 75.0dbc f i g u r e 21 . fft f in = 40 0 m hz , a in = ?1 d b f s , d i t h er o n , r e g is t e r 0x 22a = 0x 0 2 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 50 100 150 12169- 207 m ag ni t ude ( d b) f in (mh z) a in = ?7d bf s s nrf s = 71. 9d b sfdr = 80.2dbc figure 22 . fft f in = 400 mhz, a in = ?7 dbfs, dither on , register 0x22a = 0x02 140 20 78 60 62 64 66 68 70 72 74 76 40 60 80 100 120 s nr ( d b) s f dr ( d b) ?80 ?60 ?40 ?20 0 12169- 114 a in ( ?dbfs ) sf d r ( d b c) , ?40 c s fdr (dbc), +25c s fdr (dbc), +85c sf dr ( d bf s ) , ? 4 0 c s fdr (dbfs), +25c sfdr (dbfs), +85c snrf s ( d b) , ? 4 0 c s nrf s ( d b) , + 2 5 c s nrfs (db), +85c figu r e 23 . s i ng l e t o ne sn r / sf dr v s . i np ut a m p l i t ud e ( a in ) w i t h f in = 9 0. 1 m hz , v re f = 1 . 2 5 v , o v e r t em p era t u re, d i t h er o n re v . a | page 15 of 36
AD9652 data sheet 140 20 78 60 62 64 66 68 70 72 74 76 40 60 80 100 120 ?80 ?60 ?40 ?20 0 s nr ( d b) s f dr ( d b) ?80 ?60 ?40 ?20 0 12169- 015 a in ( ?dbfs ) sfdr (dbc), ?40c sfdr (dbc), +25c sfdr (dbc), +85c sfdr (dbfs), ?40c sfdr (dbfs), +25c sfdr (dbfs), +85c s nrf s ( d b) , ? 4 0 c s nrf s ( d b) , + 2 5 c snrfs (db), +85c fi g u r e 24 . s i ng l e t o ne sn r / sf dr v s . i np ut a m p l i t ud e ( a in ) w i t h f in = 9 0. 1 m hz , v re f = 1 . 0 v , o v er t e m p era t u re, d i t h er o f f 76 74 72 70 68 66 64 62 60 58 56 110 70 74 78 82 86 90 94 98 102 106 0 50 100 150 200 250 300 350 400 450 500 550 12169- 116 s nr ( d b) s f dr ( d bc) f in (mh z) sf dr ( n yq u i st set t i n g 1 ) s f dr ( nyquist setting 2) s f dr ( nyquist setting 3) snrf s ( n yq u i st set t i n g 1 ) s nrf s ( nyquist setting 2) s nrf s ( nyquist setting 3) f i g u r e 25 . s i ng l e t o ne sn r / sf dr v s . i np ut f r e q u e nc y ( f in ) , a m pl i t u de = ? 1 db fs , v re f = 1. 25 v 76 74 72 70 68 66 64 62 60 58 56 110 70 74 78 82 86 90 94 98 102 106 0 50 100 150 200 250 300 350 400 450 500 550 12169- 017 s nr ( d b) s f dr ( d bc) f in (mh z) sf dr ( n yq u i st set t i n g 1 ) s f dr ( nyquist setting 2) s f dr ( nyquist setting 3) snrf s ( n yq u i st set t i n g 1 ) s nrf s ( nyquist setting 2) s nrf s ( nyquist setting 3) f i g u r e 26 . s i ng l e t o ne sn r / sf dr v s . i np ut f r e q u e nc y ( f in ) , a m pl i t u de = ? 7 db fs , v re f = 1. 25 v 140 20 78 60 62 64 66 68 70 72 74 76 40 60 80 100 120 ?80 ?60 ?40 ?20 0 s nr ( d b) s f dr ( d b) ?80 ?60 ?40 ?20 0 12169- 115 a in ( ?dbfs ) s fdr (dbc), ?40c sfdr (dbc), +25c sfdr (dbc), +85c sfdr (dbfs), ?40c sfdr (dbfs), +25c sfdr (dbfs), +85c s nrf s ( d b) , ? 4 0 c s nrf s ( d b) , + 2 5 c snrfs (db), +85c figu r e 27 . s i ng l e t o ne sn r / sf dr v s . i np ut a m p l i t ud e ( a in ) w i t h f in = 90. 1 m hz , v re f = 1 . 0 v , o v e r t e m p er a t u re, d i t he r o n 76 74 72 70 68 66 64 62 60 58 56 110 70 74 78 82 86 90 94 98 102 106 0 50 100 150 200 250 300 350 400 450 500 550 12169- 016 s nr ( d b) s f dr ( d b) f in (mh z) s f dr ( n yq u i st set t i n g 1 ) s f dr ( n yq u ist setting 2) s f dr ( n yq u ist setting 3) snrfs (n yq u i st set t i n g 1 ) s nrf s ( n yq u ist setting 2) s nrf s ( n yq u ist setting 3) f i g u r e 28 . s i ng l e t o ne sn r / sf dr v s . i np ut f r e q u e nc y ( f in ) , a m pl i t u de = ? 1 db fs , v re f = 1 . 0 v 76 74 72 70 68 66 64 62 60 58 56 110 70 74 78 82 86 90 94 98 102 106 0 50 100 150 200 250 300 350 400 450 500 550 12169- 117 s nr ( d b) s f dr ( d bc) f in (mh z) s f dr ( n yq u i st set t i n g 1 ) s f dr ( n yq u ist setting 2) s f dr ( n yq u ist setting 3) snrfs (n yq u i st set t i n g 1 ) s nrf s ( n yq u ist setting 2) s nrf s ( n yq u ist setting 3) f i g u r e 29 . s i ng l e t o ne sn r / sf dr v s . i np ut f r e q u e nc y ( f in ) , a m p l i t u d e = ? 7 d b f s, v re f = 1 . 0 v re v . a | page 16 of 36
d ata she et ad 9652 0 ?120 ?100 ?80 ?60 ?40 ?20 105 100 95 90 85 80 75 ?80 ?60 ?40 ?20 0 12169- 329 i m d ( d b) s f dr ( d bf s ) in p u t a m p litu d e ( db fs ) imd2 (dbc) imd3 (dbc) imd2 (dbfs) imd3 (dbfs) sfdr (dbfs) figure 30 . two tone sfdr/ intermodulation distortion ( imd ) vs . input amplitude, for f in = 70.1 mhz and 72.1 mhz, dither d isabled 0 ?120 ?100 ?80 ?60 ?40 ?20 105 100 95 90 85 80 75 ?80 ?60 ?40 ?20 0 12169- 330 i m d ( d b) s f dr ( d bf s ) in p u t a m p litu d e ( db fs ) imd2 (dbc) imd3 (dbc) imd2 (dbfs) imd3 (dbfs) sfdr (dbfs) figure 31 . two tone sfdr/imd vs . input amplitude, for f in = 184 mhz and 187 mhz, dither d isabled , register 0x22a = 0x01 0 ?140 ?120 ?100 ?80 ?60 ?40 ?20 0 150 125 100 75 50 25 am p l i t ude ( d b) f in (mh z) a in 1 = a in 2 = ?7d bf s s f dr = 87d bc ( 94d bf s ) i m d2 = ?92d bc ( ?99d bf s ) i m d3 = ?87d bc ( ?94d bf s ) 12169-331 f i g u r e 32 . t wo to n e f f t w i t h f in = 89 . 1 m h z a n d 92 . 1 m h z , v r ef = 1. 2 5 v 0 ?120 ?100 ?80 ?60 ?40 ?20 105 100 95 90 85 80 75 ?80 ?60 ?40 ?20 0 12169- 332 i m d ( d b) s f dr ( d bf s ) in p u t a m p litu d e ( db fs ) imd2 (dbc) imd3 (dbc) imd2 (dbfs) imd3 (dbfs) sfdr (dbfs) figure 33 . two tone sfdr/ imd vs. input amplitude, for f in = 70.1 mhz and 72.1 mhz, dither e nabled 0 ?120 ?100 ?80 ?60 ?40 ?20 105 100 95 90 85 80 75 ?80 ?60 ?40 ?20 0 12169- 333 i m d ( d b) s f dr ( d bf s ) in p u t a m p litu d e ( db fs ) imd2 (dbc) imd3 (dbc) imd2 (dbfs) imd3 (dbfs) sfdr (dbfs) figure 34 . two tone sfdr/imd vs . input amplitude, for f in = 184 mhz and 187 mhz, dither e nabled , register 0x22a = 0x01 70000 0 10000 20000 30000 40000 50000 60000 n ? 20 n ? 18 n ? 16 n ? 14 n ? 12 n ? 10 n ? 8 n ? 6 n ? 4 n ? 2 n + 2 0 n + 1 8 n + 1 6 n + 1 4 n + 1 2 n + 1 0 n + 8 n + 6 n + 4 n + 2 n 12169- 026 num be r o f hi t s co de s figure 35 . grounded input histogram rev. a | page 17 of 36
AD9652 data sheet 100 70 75 80 85 90 95 80 120 160 200 240 280 320 12169- 335 s nrf s / s f dr ( d b/ d bc) e nco de rat e ( m hz ) snrfs (v ref = 1v) s f dr ( v re f = 1v ) sn r f s (v re f = 1. 25v ) s f dr ( v re f = 1. 25v ) f i g u r e 36 . e nc o d e r a t e swe e p , f in = 9 0. 1 m h z at ?7 d bf s , v re f = 1. 25 v an d 1. 0 v 1. 0 ?1.0 ?0. 8 ?0. 6 ?0. 4 ?0. 2 0 0. 2 0. 4 0. 6 0. 8 0 10000 20000 30000 40000 50000 60000 12169- 024 dnl ( l s b) co de s f i g u r e 37 . d nl w i t h di t h e r o f f , f in = 3 0 m h z 1. 0 ?1.0 ?0. 8 ?0. 6 ?0. 4 ?0. 2 0 0. 2 0. 4 0. 6 0. 8 0 10000 20000 30000 40000 50000 60000 12169- 025 dnl ( l s b) co de s f i g u r e 38 . d nl w it h d i t h er o n , f in = 3 0 m h z 100 70 75 80 85 90 95 80 120 160 200 240 280 320 12169- 338 s nrf s / s f dr ( d b/ d bc) e nco de rat e ( m hz ) snrfs (v ref = 1v) s f dr ( v re f = 1v ) sn r f s (v re f = 1. 25v ) s f dr ( v re f = 1. 25v ) f i g u r e 39 . e nc o d e r a t e swe e p , f in = 90 . 1 m h z a t ? 1 d bf s , v re f = 1. 25 v an d 1. 0 v 6 ?6 ?3 0 3 0 10000 20000 30000 40000 50000 60000 12169- 124 in l ( ls b ) co de s f i g u r e 40 . in l wi t h di t he r o f f , f in = 3 0 m hz 6 ?6 ?3 0 3 0 10000 20000 30000 40000 50000 60000 12169- 125 in l ( ls b ) co de s f i g u r e 41 . in l wi t h di t he r o n, f in = 30 m hz rev. a | page 18 of 36
d ata she et ad 9652 equivalent circuits 12169-027 v i n x avdd3 27k figure 42 . equivalent analog input circuit 0. 9v 10k? 10k? clk+ clk? av dd_cl k avdd av dd 12169-028 f i g u r e 43 . e q ui v a l e nt c l o c k l np ut c i r c ui t dr vd d da t a o u t + v? v+ da t a o u t ? v+ v? 12169- 029 f i g u r e 44 . e q ui v a l e nt l v ds o ut p ut c i r c u it ( dc o , o r , a nd d0 to d 15 ) 12169- 030 s di o 350? 26k? spi vd d f i g u r e 45 . e q ui v a l e nt sdio c i r c u it 12169- 300 p dw n 350? 26k? f i g u r e 46 . e q ui v a l e nt pd w n inp ut c i r c ui t 26k? 350? spi vd d sclk 12169- 339 f i g u r e 47 . e q ui v a l e nt sc l k inp ut c i r c u i t cs b 350? 26k? spi vd d 12169- 032 f i g u r e 48 . e q u iv al e n t c sb inp ut c ir c u it av dd_cl k av dd_cl k 16k? 0. 9v 0. 9v syn c 12169-033 fi g u r e 49 . e q ui v a l e nt sy nc inp ut c i r c ui t 350? 12168- 208 avdd sen se f i g u r e 50 . e q ui v a l e nt se nse c ir c u i t 12169-209 6k? av dd vr ef f i g u r e 51 . e q ui v a l e nt vr e f c ir c u i t re v . a | p a ge 19 of 36
AD9652 data sheet t he o r y o f ope ra t i on th e a d 9652 is a d u a l , 1 6 - b i t ad c wi t h s a m p l i n g s p eed s o f up t o 3 10 ms p s . t he a d 9652 i s d es i g n e d t o s u p p o r t co m m un i ca t i o n s a nd in s t r u m e n t a t io n a p p l i c a t io n s w h e r e h ig h p e r f o r m a n c e a nd wi d e b a n d w i d t h a r e d es i r e d. t h e d u a l ad c d es i g n c a n b e u s ed f o r d i v er s i ty r ec e i v e rs , w he r e t he ad c s o p er a t e i d e n t i c a l l y o n t h e s a m e c a r r i er b ut f r o m t wo s e p a r a t e a n t e n n a e. t h e ad c s c a n a l s o b e o p er a t e d wi t h i nde p e n de n t a n a l o g i n p u t s. t he u s e r c an s a m p l e f r e q u en c i es f rom d c t o 3 1 0 m hz u s i n g ap p r o p r i at e l o w - p a s s or b a n d - p a ss f i l t er i n g a t t h e ad c i n p u ts w it h l it t l e l o s s i n a d c p e r f o r m anc e . a t y pi c a l o p e r at i o n of 4 8 5 m hz a t th e an a l o g in p u t is p e r m i t t e d b u t o c c u r s a t t h e ex p en s e o f i n c r e a s e d ad c n o i s e a n d d i s t o r t i o n . s y n c h ron i z a t i on c a p ab i l i t y is p r o v id e d t o a l l o w s y n c hr o n i ze d ti m i n g bet w een m u l t i p le d e v i c e s. p ro g r a m m i n g a n d c on t ro l of t h e a d 9652 a re a c c o m p li sh e d u si n g a 3 - w i re , sp i - c o m p at i b l e s e r ia l in t e r f ac e . a d c a r ch i t ect ur e th e a d 9652 c o n sis t s o f a d u a l, bu f f e r e d f ron t - e nd s a m p l e - a nd - ho ld c i r c u i t , f o l lo w e d b y a p i p e li n e d s w it c h e d - c ap a c it o r ad c . th e ad9 6 52 u s e s a u n iq u e a r c hi t e c t u r e t ha t u t il i z e s t h e b e n ef i ts o f p i p e l i n e d c o n v e r t e r s, a s w e l l a s a n o vel i n p u t c i r c u i t t o m ax im i z e p e r f o r m anc e o f t he f i r s t s t ag e . t h e q u an t i z e d o u t p u t s f r o m e a c h s t ag e ar e c o mb i ne d t o p r o d uce a 16 - bi t r es u l t i n t h e d i g i t a l c o r r e c t io n l o g ic . t he p i p e l i n e d a r c h i te c t u r e p er m i ts t h e f i r s t s t a g e t o o p er a t e o n a n e w i n p u t s a m p l e , a n d t h e r em a i n i n g s t a g es t o o p er a t e o n t h e p r e c e d i n g s a m p le s. s a m p li n g o c c u r s o n t h e r i si n g e d g e o f t h e cl o ck . e ac h s t a g e o f t he p i p e l i n e , e x c l u d in g t h e l a s t , c o n si s t s o f a lo w r e s o l u t io n f l as h a d c c o n n e c t e d t o a s w i t c h e d - c a p a c it o r d i g it a l - t o - an a l o g c o n v e r t e r ( d a c ) an d an i n t e r s t ag e re s i d u a l m u l t i p l y i n g da c ( m d a c ) . t h e m d a c m a g n i f i e s t h e d i f f er en c e b e tw e en t h e re c on s t r u c t e d d a c o u t p u t an d t he f l as h i np u t f o r t h e n e x t s t a g e i n t h e p i p e l i n e . o n e b i t o f r e d u n d a n c y i s u s e d i n e ac h s t ag e t o f ac i l i t a t e d ig i t a l c o r r e c t io n o f f l as h e r r o r s . t h e la s t s t a g e c o n si s t s o f a f la sh a d c. th e a d 9652 u s es i n ter n a l d i g i t a l p r o c e s si n g t o c o n t i n u a l l y t r ac k in t e r n al e r ror s t ha t o c c u r a t e ac h o f t he p i p e l in e s t a g e s an d c or re c t s f or t h e m t o e n s u re c on t i n u ou s p e r f or m a n c e o v e r v a r i ou s op e r a t i n g c on d i t i on s . t his r e q u ir e s add i t i o nal s t a r t - up t i m e d u e t o t h e r es et t i n g a n d c o l le c t i on of c or re c t i on d a t a . t he i n p u t s t a g e o f e ac h c ha n n e l c o n t a i n s a d if f e r e n t ia l s am p l in g c i r c u i t t h a t c a n b e a c - or d c - c o u p l e d in d if f e r e n t ia l o r s in g l e - e n d e d m o d e s. t h e o u t p u t s t a g i n g b lo c k a l i g n s t h e d a t a , c o r r e c t s er r o r s, a n d p a s s es t h e d a t a t o t h e o u t p u t b u f f er s. t h e o u t p u t b u f f er s a r e p o w er e d f r o m a s ep a r a t e s u p p l y , a l l o w i n g d i g i t a l ou t p u t n oi s e t o b e s e p a r a t e d f r om t h e a n a l o g c or e . d u r i n g p ow e r - d o wn , t h e o u t p u t b u f f er s en t er a hig h i m p e d an c e s t a t e . a n a l og i n p u t c ons i d e r a t io n s th e a na l o g i n p u t s t o t he a d 96 52 a re hig h p e r f o r m a n c e d i f f er en t i a l bu f f e r s t h at a r e de s i g ne d f o r o p t i m u m p e r f o r m anc e w hi l e p r o c e s s in g a d if f e r e n t ia l i n p u t s ig n a l . t he in p u t b u f f e r p r o v id e s a c o n s i s t e nt i n p u t im p e d an c e t o e a s e i n t er f a c e o f t h e a n a lo g i n p u t . th e d if f e r e n t ia l a n a lo g in p u t i m p e d an c e is a p p r o x im a t e l y 54 k ? in p a r a l l e l w i t h a 5.8 pf ca p a c i t o r . a p a s s i v e n e t w or k o f d i s c r ete co m p o n e n t s ca n b e us e d t o c r e at e a l o w - p a s s f i l t er a t t h e ad c i n p u t; t h e p r e c i s e va l u es a r e d ep en d en t o n t h e a p p l i c a t i o n . i n i n t e r me d i a t e f r e q u e nc y ( i f ) u nd e r s am p l i ng a p p l i c a t i o ns , r e d uce t he s hu n t c ap a c i t o r s. i n c o m b in a t io n w i t h t h e d r i v in g s o u r c e i m p e d anc e , t he s h u n t c a p a c i t o r s l i m i t t he in p u t b andw i d t h . ref er t o t h e a n a l o g d i a l o g ue ar t i c l e , t r ans f o r me r - c o up l e d f ron t - e n d f o r w i d eb a n d a/d c o n v er t e r s , f or m ore i n f or m a t i on o n t his s u b j e c t . th e a d 9652 u s es i n ter n a l o p t i m i z e d s e t t i n g s f o r t h e va r i ou s i n p u t si g n a l f r e q u e n c i e s. r eg i s ter 0 x 2 2 a i s u s e d t o c o n f i g u r e t h e a d c f o r th e d es i r ed f r eq u e n c y ba n d . ta bl e 9. r e g i ste r 0 x 22a s e tti n g s r eg i st er 0 x 22a s e tti n g i n p ut f r e q ue n c y r a ng e 0 ( d e f au lt ] 0 to 155 mhz (1 st nyquist) 1 155 t o 3 10 m h z (2 nd n yquist) 2 3 1 0 m h z a n d a bov e (3 rd n yq u ist) f o r b es t d y n a m i c p er f o r m a n c e , t h e s o u r c e i m p e d a n c es d r i vi n g e a c h o f t h e d i f f er en t i a l i n p u ts , m a t c h v i n x , an d d if f e r e n t ia l l y b a l a n c e t h e i n p u ts . i n p u t com m on m od e t h e a n a lo g i n p u t s o f t he ad9 6 5 2 a r e n o t i n ter n a l l y d c b ias e d . in a c - c o u p l e d a p p l ic a t io n s , t h e u s e r m u s t p r o v i d e t his b ias ex t er n a l l y . s e t t i n g t h e d e vi c e s o t h a t t h e c o m m on - mo d e v o l t a g e e qu a ls 2 .0 v is re c o m m e n d e d f o r o p t im u m p e r f o r m a n c e . a n on - b o a rd c om m on - m o d e v o l t a g e r ef er en c e i s i n c l u d e d i n t h e de s i g n a nd i s a v a i l a b l e f r o m t h e vc m pi n . u si n g t h e v c m o u t p u t t o s et t h e i n p u t c o m m o n m o d e i s r e c o m m en d e d . t he v c m p i n m us t b e d e co u p l e d t o g rou n d wi th a 0. 1 f ca p a ci t o r , a s de s c r i b e d i n t h e a p p l ic a t io n s i n f or m a t i on s ec ti o n . pla c e t hi s d e c o u p l in g c a p ac i t o r c l o s e t o t h e p in t o m in i m i ze t h e s e r ie s r es i s t a n c e a n d i n d u c t a n c e b e tw e en t h e de v i c e an d t his c a p ac i t o r. com m on - mo d e v o l ta g e se r v o i n a p p l i c a t i o n s w h er e t h er e m a y b e a v o l t a g e l o s s b e tw e en t h e vcm ou t p u t o f th e a d 9652 and t he an a l o g i n p u t s , t he c o m mo n - mo d e v o l t ag e s e r v o c an b e e n ab l e d. wh e n t he i n p u ts a r e ac - c o up l e d a nd a r e s i s ta n c e o f >1 0 0 ? i s p l a c ed bet w een t h e v c m o u t p u t a n d t h e a n a lo g i n p u t s, a si g n if ic an t v o l t a g e d r o p ca n o cc ur ; e n a b l e t h e c om m on - mo d e v o l t ag e s e r v o . se tt i n g b i t 0 i n r eg i s t er 0 x 0 f t o a l o g ic hig h e n a b l e s t he v c m s e r v o mo d e . i n t h i s mo de , t h e ad9 6 5 2 m on i t or s t h e c om m o n - mo d e rev. a | page 20 of 36
data sheet AD9652 rev. a | page 21 of 36 in p u t le ve l a t t h e a n alog in p u ts a nd ad j u sts t h e v cm o u t p u t l e vel to ke e p t h e c o mmon- m o d e i n put vol t age a t an opt i m a l le v e l . i f both c h a nne ls a r e o p er a t io nal , c h ann e l a is m o n i t o r e d . h o w e v e r , i f ch a n n e l a is in p o wer - do w n o r st andb y mo de, t h en c h a nne l b in put is m o n i t o r e d . dither th e AD9652 h a s a n o p ti o n al i n t e rn al d i t h e r ci r c ui tr y th a t ca n b e us e d t o im p r o v e s f dr , p a r t ic u l a r ly f o r sm a l l s i g n a l s. d i t h e r i n g i s th e a c t of i n j e c t i n g a k n ow n but r a nd o m a m ou n t of w h ite noi s e in t o t h e in p u t o f t h e AD9652 . di th er in g ha s t h e e f fe c t o f im p r o v in g th e local l i ne a r i t y w i th i n th e a d c tr a n s f e r fun c ti o n . t h e ad965 2 a l l o w s di t h er to b e a dde d t o e i t h e r ad c in p u t i n d e p e nden t ly . t h e f u l l s cale o f t h e di t h er d a c i s s m a l l en o ug h t h a t ena b li n g di t h er do es n o t limi t t h e ext er n al in p u t sig n a l am pli t ude. a s sho w n i n f i g u r e 52, t h e di t h er t h a t is adde d to t h e in p u t o f t h e a d c th r o u g h th e d i th e r d a c i s p r e c i s e l y s u b t r a ct ed o u t d i gi tall y t o m i nim i z e s n r degrada t i o n . w h en di t h er i n g i s ena b le d, t h e di t h er d a c is dr i ven b y a ps eudo r a n d om n u m b er g e n e ra t o r (p n gen ) . i n t h e ad9 652 , t h e di t h er d a c is p r e c is e ly ca l i b r a t e d t o r e su l t in o n ly a ver y sma l l deg r ad a t io n i n s n r an d s in a d w h en di th er is enab led . adc core dither dac pn g en di t h er enable AD9652 vin x do ut 12 16 9- 03 4 f i gu r e 52 . di th er blo c k di a g r am the s f d r i m p r o v emen t com es a t t h e exp e n s e of s n r deg r a d a t io n, b u t b e ca us e t h e d i t h er is i n ter n a l a nd can b e co rr e l a t e d , t h e im pa ct o n s n r is t yp i call y li m i t e d t o le s s th a n 0.5 db i n t h e f i r s t n y q u ist zo ne. ena b li n g i n ter n a l d i t h er do es not i m p a c t f u l l - s c a l e dy n am i c r ange. t he m ag n i t u d e of d i t he r i s co n t r o l la b le , whic h al lo ws t h e us er t o s e le c t t h e desir e d trade- o f f be t w een s f d r i m p r o v em en t v s. s n r d e gra d a t i o n . t o enab le di t h er , s e t bi t 4 o f reg i s t er 0x30. t o mo dif y t h e di t h er ga in, us e reg i s t er 0x212[7:4]. table 10. dither gain regist er 0x212 [7:4] s e tting g a in r a tio g a in (%) 0b0000 (default) maximum dither 100 0b0001 255/256 max 99.6 0b0010 254/256 max 99.2 0b0011 252/256 max 98.4 0b0100 248/256 max 96.8 0b0101 240/256 max 93.75 0b0110 224/256 max 87.5 0b0111 192/256 max 75 0b1000 m i nimum dither 50 l a rge s i g n a l f a st f o uri e r t r an sf o rm i n m o s t cas es, di t h er in g do es no t im p r o ve s f d r fo r la rg e sig n al in p u ts c los e t o f u l l s cale , f o r exa m p le , wi t h a ?1 db fs in p u t. f o r la rge sig n a l i n pu ts, t h e s f d r is typ i ca l l y li mi t e d b y f r o n t-e nd s a m p l i ng di s t or t i on, w h i c h d i t h e r i n g c a n n ot i m pro ve. h o w e ve r , e v en fo r s u ch l a rg e sig n al in p u t s , di t h er in g ma y b e us ef u l fo r cer t a i n a p plic a t i o n s b e ca us e i t mak es t h e n o is e f l o o r w h i t er . a s is co mm on i n pi p e li n e ad cs, t h e AD9652 co n t a i n s smal l dnl e r ror s c a u s e d by r a nd om c o m p one n t m i s m a t c h e s t h a t pro d u c e spu r s or tone s t h a t m a k e t he no i s e f l o o r s o me w h a t r a nd om ly colo r e d de vice -to-de vic e . al t h oug h t h es e t o n es a r e typ i cal l y a t v er y lo w le v e l s a nd do n o t limi t s f d r w h en t h e ad c is q u a n tiz i n g la r g e si gn al i n p u t s , di t h e r i n g co n v e r ts th ese t o n e s t o n o is e and p r o d uces a w h i t er no is e f l o o r . sm a l l si g n a l f f t f o r sma l l sig n a l in p u ts, t h e f r o n t-e n d s a m p li n g cir c ui t typ i ca l l y co n t r i b u t e s ver y li t t le dis t o r tion, an d t h e s f d r is lik e l y t o be l i mite d b y tone s c a u s e d b y dn l e r rors d u e to r a ndom co m p on e n t mis m a t ch es. th er efo r e , fo r smal l si g n al in p u ts (typ icall y , t h os e be lo w ?6 db fs), d i t h er in g can sign ifi can t l y im p r o v e s f d r b y co n ver t i n g t h es e d n l t o n es t o w h i t e n o is e . st at i c l i n e a r i t y d i th e r i n g a l s o r e m o v e s s h a r p l o c a l d i s c o n ti n u i t i e s i n th e in l t r a n sfer f u n c t i o n o f t h e ad c and r e d u ces t h e o v eral l p e a k -t o - p e ak i n l. u t ilizin g di t h er ra n d o m izes lo c a l smal l sig n al d n l er r o rs tha t p r o d uce t h e dis c o n t i n u i t ies i n t h e i n l t r a n sfer f u n c t i on an d t h er efo r e im p r o v e t h e p e ak- t o- p e ak i n l p er f o r ma n c e . differenti a l input config urations o p t i m u m p er f o r ma n c e is achi e v e d b y dr ivin g t h e AD9652 in a dif f er en t i a l i n p u t co nf igur a t io n. f o r b a s eb a nd a p plica t io n s, t h e ad l5566 , ad8 138 , ad a4937 -2 , ad a4938-2 , a nd ad a4930-2 dif f er en t i al dr i vers p r o v i d e e x c e l l e n t p e r f o r m a n c e a n d a fl e x i b l e in t er f ace t o t h e ad c. the o u t p u t co mm o n - m o d e v o l t a g e o f t h e ad a4930-2 is e a si ly s e t w i t h th e v c m p i n o f th e AD9652 (s ee f i gu r e 53), a n d the dr i v er can b e conf igur e d in a sa l l en- k e y f i l t er to p o lo g y to p r o v ide b a nd li mi t i n g o f t h e i n p u t sig n al . vi n x 76. 8 ? 12 0 ? 0. 1 f 200 ? 200 ? 90 ? 0.1f 33 ? 33 ? 33 ? 15 ? 15 ? 5p f 15p f 15p f adc vin? x vi n + x vc m ada 493 0- 2 1216 9- 035 figure 53. d i f f er ent ia l input c o nf ig u r a t ion u s i n g t h e a d a 49 30- 2 f o r b a s eb a nd a p plica t io n s w h e r e s n r is a ke y p a ra m et er , dif f er en t i a l t r a n sfo r m er co u p ling is t h e r e co m m ende d in pu t
AD9652 data sheet rev. a | page 22 of 36 co nf igura t io n. an exa m ple is sh o w n i n f i gur e 54. t o b i as t h e a n alog in p u t, t h e v c m v o l t a g e ca n b e co nn e c t e d t o t h e ce n t er ta p o f th e seco n d a r y w i n d i n g o f th e tra n sf o r m e r . 2 v p- p 49.9 ? 0.1f r1 r1 c1 ad c vin+x vi n ? x vcm c2 r2 r3 r2 c2 r3 0.1f 33 ? 12169-036 fig u re 5 4 . d i f f er ent ia l t r ans f o r m er-c o upled c o nf ig u r at io n the sig n al c h a r ac t e r i s t ics m us t be co n sider e d w h e n s e le c t in g a tra n sfo r m e r . m o s t rf tra n sfo r m e rs s a t ur a t e a t f r e q uen c ies b e lo w a fe w m e ga h er t z. e x cessi v e sig n a l p o w er ca n a l s o c a us e c ore s a tu r a t i on , w h i c h l e a d s to d i stor t i on . a t in pu t f r e q uen c ies in t h e s e c o n d n y q u ist zon e and ab o v e, t h e n o is e p er f o r ma n c e o f m o st am plif iers is n o t a d e q ua t e t o ach i e ve th e tr ue s n r perf o r m a n c e o f t h e AD9652 . f o r a p plica t io n s w h e r e s n r is a k e y p a ra m e t e r , d i f f e r en tial do u b le bal u n c o u p lin g i s t h e r e co m m e n d e d i n p u t conf igur a t io n (s e e f i g u r e 56). i n t h is co nf igura t io n, t h e in pu t is ac-c o u ple d an d t h e v c m v o l t a g e is pro v i d e d to e a c h i n put t h rou g h a 3 3 re si stor . t h e s e re si stor s co m p ens a te fo r los s es in t h e i n pu t b a l u ns t o p r o v ide a 50 im p e dan c e t o t h e dr i v er . i n t h e do ub le b a l u n and t r a n sfo r m er co nf igur a t io n s, t h e va l u e o f t h e i n p u t c a p a ci to rs an d r e sisto r s is dep e nde n t o n t h e i n p u t f r e q uen c y a n d s o ur ce im p e dan c e. b a s e d o n t h e s e p a r a m e ters, t h e val u e o f t h e in p u t r e sis t o r s a nd ca p a c i t o rs ma y n e e d t o b e a d ju s t e d , o r s o m e co m p o n en ts ma y n eed t o be r e m o v e d . t a b l e 1 1 d i s p l a y s r e c o m m e n d e d v a l u e s to s et t h e r c n etw o r k fo r di f f e r en t in p u t f r e q uen c y ra n g es. h o w e ver , t h es e val u es a r e dep e nden t o n t h e in p u t sig n al; us e t h e b a n d wi d t h onl y as a s t ar t i n g guide . n o t e t h a t t h e va l u es g i v en i n t a b l e 11 a r e fo r e a ch r1, r2, c1 , c2, a nd r3 com p o n en t sh o w n in f i gur e 54 and f i gur e 56. table 11. e x am ple r c networ k freq uenc y ran g e (mhz) r1 series () c1 diff eren tia l (pf) r2 serie s () c2 shunt (pf) r3 shunt () 0 to 100 33 open 0 15 49.9 100 to 300 15 open 15 2.7 0 an a l ternative to using a transformer-coupled input at frequencies in the second nyquist zone is to use an amplifier with variable gain. the ad8375 or ad8376 digital variable gain amplifier (dvga) provides good performance for driving the AD9652 . figure 55 shows an example of the ad8376 driving the AD9652 through a band-pass antialiasing filter. a d 83 76 a d 96 52 1 h 1h 1nf 1n f vpo s vc m 15 p f 68n h 54 k ?U 2. 9 p f 30 1 ? 16 5 ? 16 5 ? 5. 1 p f 3. 9 p f 18 0n h 100 0p f 100 0p f no t e s 1. al l i n duc t o rs ar e c o i l cr af t ? 0 6 0 3 c s c o m p o n e n t s w i th th e excep t i o n o f t h e 1 h ch o k e i n du ct o r s ( c o i l cr af t 0 6 0 3 l s ) . 2 . f i l t er val u es sho w n ar e f o r a 2 0 m h z b a n d w i dt h f i l t e r c e n t er ed a t 1 4 0 mh z . 18 0n h 220 n h 220 n h 12 169- 0 37 fig u re 5 5 . d i f f er ent ia l input c o nf ig u r a t ion u s i n g t h e ad83 76 adc r1 0.1f 0.1f 2v p - p vi n + x vi n ? x c1 c2 r1 r2 r2 0. 1 f s 0. 1 f c2 33 ? 33 ? s p a p r3 r3 0.1 f 33 ? vc m 121 69- 038 figure 56. d i ffer e nt ial d o uble b a lun in put configu r ation table 12. v re f con f iguration op tion s s e lec t e d mode sense voltage resulting a d c ref e renc e v o lt age ( v ) resulting input span (diff e r e n tial v p - p) external reference avdd n/a 1 2 external reference internal fixed reference gnd v ref 2 2 v ref 2 1 n/a = not appl ica b l e . 2 v re f is set via register 0x18. the default v re f is 1.25 v.
d ata she et ad 9652 v o l t a g e r ef e r e n c e a s t a b l e a n d a c c u r a t e v o l t a g e r ef er en c e i s b u i l t i n t o t h e a d 9652 . th e f ul l - sc a l e i np u t r a n g e c a n b e a dju s t e d b y v ar y i n g t h e r e f er en c e v o l t a g e v ia t he spi . t h e i n p u t s p a n o f t h e ad c l i n e ar l y t r ac ks r ef er en c e v o l t a g e c h a n g es . i n t er n a l r ef e r en c e c o n n ect i o n a s t a b l e a n d a c c u r a t e p r o g r am m ab l e r ef er en c e i s b u i l t i n t o t he a d 9652 , a l l o w i n g a v o l t a g e r ef er en c e f rom 1 .0 v t o 1 .2 5 v t o p r o v i d e u p t o a 2 . 5 v p - p d if f e r e n t ia l f ul l - s c a l e i n p u t. by d ef a u l t t h e v r ef v o l t a g e i s s e t 1 . 2 5 v , b u t c a n b e m o d if ie d u s in g reg i st er 0 x 1 8 [ 2 :0 ] , v r ef s el e c t . t o c on f i g u re t h e a d 9652 f o r a n i n t er n a l r ef er en c e, t h e s e n s e p i n m u s t b e t i e d l o w . w h e n s e n s e i s t i e d lo w , t h e a d c u s e s v r ef di r e c t l y a nd p r o v i de s a d if f e r e n t ia l i n p u t v o l t a g e of t wo t i me s t he v r ef v a l u e . t o ac h ie v e o p t i m a l no i s e p e r f o r m anc e w he n u si ng t he i n t e r n a l r ef er en c e , i t is re c o m m e n d e d t ha t t h e v re f p i n b e d e c o u p l e d by 1. 0 f a n d 0. 1 f ca p a ci t o r s c l o s e t o t h e p i n . fi g u r e 57 sh o w s t h e c o n f i g u r a t i o n f o r t h e i n t er n a l r ef er en c e c o n n e c t i o n r e s u l t i ng in a in p u t v o l t ag e s e t b y v r e f , t ha t is , a 2. 5 v p - p d if f e r e n t ia l f ul l - s c a l e i np u t . vref v select AD9652 select logic 0.1f 1. 0 f v i n?a/vin?b v i n+ a/ v i n+ b adc co re sense 12169-039 f i g u r e 57 . i nt ern a l r ef eren ce c o nf i g u r a t i o n i f t h e i n t er n a l r ef er en c e o f t h e ad9 6 52 i s u s e d t o d r i ve m u l t i p l e c o n ve r t e r s t o i m p r o ve g a i n m a t c h i n g , t he l o a d i ng o f t he r e f e r e nc e b y t he o t he r c o n ver t e r s m u s t b e c on s i d e re d . f i g u re 58 sho w s ho w t h e i n t er n a l r ef er en c e v o l t a g e i s a f f e c t e d b y l o a d i n g . 0 ?1 ?2 ?3 ?4 0 2. 0 1. 8 1. 6 1.4 1.2 1. 0 0. 8 0. 6 0. 4 0. 2 12169- 056 v re f e rro r ( %) l o ad curre nt ( ma) v ref = 1.25v fig u r e 58 . r ef e ren c e v o l t a g e e rr o r v s . l o a d c u rr en t e x t er n a l r ef er en c e op e r a t i o n t h e u s e o f a n e x t er n a l r ef er en c e m a y b e n e c es s a r y t o en h a n c e t h e g ain a c c u r a c y o f t h e ad c o r im p r o v e t h e r m a l d r if t c ha r a c - t e r is t ic s . whe n t h e s e n s e p i n i s t i e d t o a vd d , t h e i n t e r n a l r ef er en c e i s d i s a b le d , a l l o wi n g t h e u s e o f a n ex t er n a l r ef er en c e t h at is a pp li e d t o t h e v r e f pi n . a n i n ter n a l r ef er en c e b u f f er l o a d s t h e ex t er n a l r ef er en c e w i t h a n e q u i va l en t 6 k ? l o a d . t h e i n t er n a l b u f f er g en er a t es t h e p o si t i v e a n d n eg a t i v e f u l l - s c a l e r ef er en c es f o r t h e ad c c o r e . t h er ef o r e , t h e ex t er n a l r ef er en c e m u s t b e l im i t e d t o a m a x im u m o f 1 . 2 5 v t o m ai n t ai n a n i n p u t v o l t ag e of 2 .5 v p-p d if f e r e n t ia l f u l l - s c a l e i n p u t o r l es s. c l oc k i np u t c o nsid e r a t io n s f or op t im u m p e r f o r m a n c e , cl o ck t he a d 9652 s a m pl e cl o ck i np u t s , c l k + a nd c l k ? , w i t h a d if f e r e n t ia l s ig n a l w i t h a h ig h s l e w r at e . t h e s ig n al i s t y p ic al l y a c - c o u p l e d i n t o t h e c lk + a nd clk ? pi n s v ia a t r ans f o r me r o r v ia c a p a c i t o r s. t h e s e p i ns ar e b i a s e d i n t e r na l l y ( s e e fi g u r e 59 ) and r e q u i r e no e x t e r n a l b i as . if t h e i n p u t s a r e f lo a t e d , t h e c l k ? p i n i s in t e n t i o n al l y b i as e d sl i g h t ly l ow er t h an cl k + t o p r e v e n t sp u r i o u s c lo c k i n g ( t his is n ot s h ow n i n fi g u re 59 ) . avdd_clk clk+ 5pf 5pf clk? 0.9v 12169-041 f i g u r e 59 . s i m p l if ie d e q ui valent cl o c k inp ut c ir c u i t rev. a | page 23 of 36
AD9652 data sheet c l o c k i n p u t o p ti o n s th e a d 9652 ha s a v e r y f l e x i b le c lo c k i n p u t s t r u c t u r e . t he c l o ck in p u t c an b e a c m o s , l v d s , l v p e cl, o r si n e w a v e si g n a l . reg a r d l es s o f t h e ty p e o f s i g n a l b ei n g u s e d , c l o ck s o ur ce j i tt e r is o f t h e m o s t c o nc e r n, a s de s c r i b e d i n t h e j i t t e r c on s i d e r a t i on s s ec ti o n . fi g u r e 60 a nd fi g u re 61 s h ow t w o p r ef er ab l e m e t ho d s f or cl o ck i n g t h e a d 9652 ( at c l o c k r at e s of up t o 1240 m hz ) . a l o w j i t t e r c l o c k s ou r c e i s c on v e r t e d f rom a s i n gl e - e nde d s i g nal t o a d i f f e r e n t i a l si g n a l u si n g a n r f b a l u n o r r f t r an s f o r me r . the r f b a l u n c o nf i g u r a t i on i s re c om m e n d e d f or c l o c k f r e q u en c i es betw ee n 1 2 5 m h z a n d 1240 m h z , an d t he r f t r a n s f or m e r i s re c om m e n d e d f or c l o c k f re q u e n c i e s f rom 80 mh z t o 200 mh z . t he b ac k - t o - b ac k s c h o t t k y d io d e s a re u s e d a c r o s s t he t r ans f o r me r s e c o n d ar y o r t he b a l u n b a l a nc e d s id e t o l i m i t cl o ck a m p l i t ud e e x c u r s io n s in t o t he a d 9652 t o ap p r o x i m at e l y 0 . 8 v p - p d if f e r e n t ia l . t his l i m it h el p s p r e ve n t l a r g e v o l t a g e s w i n g s of t h e c l o c k f rom f e e d i n g t h rou g h t o ot h e r p or t i on s of t he a d 9652 , w h i l e p r es er vi n g f a s t r i s e a n d f a l l t i m es of t h e cl o c k , w hi c h a r e c r i t ic al t o l o w j i t t er p er f o r m a n c e . 390p f 390p f 390pf schot t ky di o de s : hs m s 2822 clock input 50? 100? cl k? cl k+ adc m ini- c ircuit s ? adt 1- 1w t , 1: 1z xf mr 12169-042 f i g u r e 60 . t r a n s f or me r - c ou p l e d d if f e r e n t ia l c lo c k (u p t o 20 0 m hz ) 390pf 390pf 390pf cl o ck i np ut 1n f 25? 25? clk? clk+ schot t ky di o de s : hs m s 2822 adc 12169-043 f i g u r e 61 . b a l un- c ou p l e d d if f e r e n t ia l c lo c k ( u p t o 12 40 m hz ) i f a l o w j i t t er c l o c k s o u r c e i s n o t a va i l ab l e , an o t h e r o p t io n i s t o ac c o u p le a d i f f e r e n t i a l p e cl s i g n a l t o t h e s a m p le c lo c k i n p u t p in s as s ho w n i n fi g u r e 62 . t he a d 9510 , a d 9 511 , a d 9512 , a d 9513 , a d 9 514 , ad9 5 1 5 , ad9 5 1 6 , ad9 5 1 7 , a d 9518 , ad9 5 2 0 , ad 9522 , a d 95 23 , a d 9524 , a nd a d c lk 905 / a d c l k 907 / a d c l k 925 c l o c k d r iv e r s of f e r ex c e l l en t j i t t er p er f o r m a n c e . 100? 0. 1 f 0. 1 f 0. 1 f 0.1f 240? 240? pec l d r i ver 50k? 50k? cl k? clk+ clock i np ut cl o ck i np ut a d 95xx adc 12169- 044 f i g u r e 62 . d if f e rent ia l pe c l s a m p l e c l oc k ( u p t o 12 40 m hz ) a t hir d op t i on i s t o a c c o u p le a d i f f er en t i a l l v ds s i g n a l t o t h e s a m pl e cl o ck i n p u t p i n s , a s s h o w n i n fi g u r e 63 . th e a d 9510 , a d 9511 , a d 95 12 , a d 9513 , a d 9514 , ad9 5 1 5 , a d 9516 , a d 9 517 , a d 9518 , a d 9 520 , a d 9522 , a d 9523 , a nd ad9 5 2 4 c l o c k d r i ver s of f e r ex c el le n t j i t t e r p e r f o r m a n c e. 10 0? 0.1f 0.1f 0.1f 0.1f 50k? 50k? cl k? cl k+ clock inp ut cl o ck i np ut a d 95xx l vd s d r i ver adc 12169- 045 f i g u r e 63 . d if f e r e n t ia l l v d s s a m p l e c l oc k ( u p t o 62 5 m h z ) i n p u t c l o c k d i v i d e r th e a d 9652 c o n t a i n s a n in p u t c l o c k d iv id e r w i t h t h e ab i l i t y t o d i vi d e t h e i n p u t c lo c k b y i n teg e r va l u es of 1 , 2 , 4 or 8 . i n t h es e c a s e s, t he d c s is e n ab le d by d e f au l t o n p o w e r - u p. t he c l o c k d i vi d e r a t i o i s s et i n r eg i s t er 0 x 0 b . th e a d 9652 cl o ck d i v i d e r c an b e s y n c hr o n iz e d u s in g t h e e x t e r n a l s y n c i n p u t . b it 1 a n d b it 2 o f reg i s t er 0x 100 a l l ow t he c l o c k di v i de r t o b e r e sy n c h r o ni z e d o n e v e r y s y n c s i g na l o r o n l y o n t h e f i r s t s yn c si g n a l a f t er t h e r eg i s t er i s wr i t t e n . a va li d s y n c c a u s es t h e c lo c k d i vi d er t o r es et t o it s i n it i a l s t at e . t his s y n c hr o n i z a t i o n f e a t u r e a l l o ws m u l t i p l e d e vi c es t o h a ve t he i r c lo c k d i v i d e r s a li g ne d t o g u ar an t e e s i m u l t ane o u s i n p u t s a m p li n g. w i t h t h e di v i de r e na b l e d a n d t he s yn c o p ti o n u s ed , t h e ad c c l o c k d i vi d er o u t p u t p h a s e c a n b e a d j u s t e d af t e r s y n c h ron i z a t i on i n i nc r e me n t s o f i n p u t cl o ck c y cl e s u si n g reg i st er 0 x 1 6 . dr i v e t he s y nc i n p u t u si ng a s i ng l e - e nde d c m o s t y p e s i g na l . i f no t u s e d, c o n ne c t t he s y nc p i n t o g rou n d . cloc k d u t y cy c le t y p i c a l h i g h s p e e d a d cs u s e b o t h c lo c k e d g e s t o g en er a t e a v ari e t y o f in t e r nal t i mi n g s i g n al s an d , a s a r e su lt , m ay b e s e n si t i v e t o c lo c k d u t y c y c le . c o m m o n l y , a 5 % t o le r a n c e i s r e q u ir e d o n t he c l o c k d u t y c y c l e t o m a in t a i n d y n a m ic p e r f o r m a n c e c h a r ac t e r is t ic s . t he a d 9652 c o n t ai ns a cl o c k d cs t h a t r e t i me s t he no ns am p l i ng ( f a l li n g) e d g e , p r o v i d in g an i n t e r n a l c l o c k s ig n a l wi t h a n o m in a l 5 0 % d u ty c y c l e . t h i s a l lo w s t h e u s er t o p r o vi d e a w i d e r a n g e o f c l o c k i n p u t d u ty c y c l e s w i t h o u t a f f ec ti n g th e p e r f or m a n c e of t h e a d 9652 . j i t t e r o n t he r i si ng e d g e o f t he i n p u t cl o c k i s s t i l l o f p ar amo u n t co n cer n an d i s no t r e d uce d b y t h e d u ty c y c le s t a b i li z er . t he d c s c on t ro l l o op d o e s n o t f u n c t i on f or c lo c k r a t e s les s t h a n 8 0 m h z n o m in a l l y . t h e l o o p h as a t i m e c o n s t an t as s o c ia t e d wi t h i t t h a t m u s t b e c o n si d er e d w h e n t h e cl o ck r a t e ch a n g e s dy n am i c a l l y . a w ai t t i me o f 1. 5 s t o 5 s i s re q u i re d af t e r a d y n a m i c c l o c k f re q u e n c y i n c re a s e or d e c re a s e b e f ore t he d c s lo o p i s r e lo c k e d t o t h e i n p u t cl o ck . d u r i n g t h at t i m e p er i o d , t he lo o p i s n o t lo c k e d , t h e d cs lo o p i s b y p a s s e d , a n d i n t e r n a l d e vi c e t i m i n g i s d ep e n d en t o n t h e d u ty c y c l e o f t h e i n p u t c l o c k rev. a | page 24 of 36
d ata she et ad 9652 s i g na l . i n s o me c as e s , i t m ay b e ap p r o p r i at e t o d i s ab l e t he du t y c y c le s t a b i li z e r , f o r e x a m p l e , if a hig h q u a l i t y r f c l o c k is a va i l a b l e t o b e u s e d t o d r i v e t h e a d 9652 c l o c k i n p u t a nd do e s n ot n e e d a d j u s t m e n t i n d u t y c yc l e c or re c t i on . in mo s t ot h e r ap p l i c a t i o ns , e n ab l i ng t he d c s c i r c u i t i s r e c o m me n d e d t o m ax im i z e ac p e r f o r m a n c e . j i tte r c o n s i d e r a ti o n s h ig h s p e e d , hig h r e s o l u t io n a d c s a r e s e n s i t i v e t o t he q u a l i t y of t h e c l o c k i n p u t. t h e d eg r a d a t i o n i n s n r a t a g i v en i n p u t f r e qu e n c y ( f in ) d u e t o j i t t e r (t j ) c an b e c a l c u l at e d by snr hf = ?10 log[(2 f in t jrms ) 2 + 10 ) 10 / ( lf s nr ? ] in the equation, the rms aperture jitter represents the root - mean - square of all jitter sources, which include s the clock input, the analog input signal, and the adc apertur e jitter specification. if undersampling applications are particularly sensitive to jitter, as shown in figure 64 . 80 60 62 64 66 68 70 72 74 76 78 5 50 500 f in (mh z) s nrf s ( d b) 12169- 046 measured 0.8ps 0.2ps 0.1ps 0.05ps 0.05ps f i g u r e 64 . s n r fs v s . inp ut f r e q ue n c y a nd j i t t e r t r e at t he c l o c k i n p u t as an a n a l o g s ig n a l i n c a s es w h er e a p er t u r e j it t e r m a y af f e c t t he dy n a m i c r a ng e o f t he ad9 6 5 2 . dr i v e e x t e r n a l c lo ck s o ur ces a n d b uf f e r s f rom a c l e an ad c o u t p ut d r i v e r sup p ly t o av o i d m o d u l at i n g t h e a d c cl o ck w i t h n o i s e. l o w j i t t er , c r y s t a l c o n t r o l l e d o s c i l l a t o r s m a k e t h e b es t c l o c k s o u r c es . i f t h e c l o c k i s g e n er a t e d f r o m a n o t h er ty p e o f s o u r c e ( b y ga t i n g, d i v i d i n g, o r an o t he r me t h od ) , r et i m e i t by t he o r ig in a l c l o c k a t t h e l as t s t e p . ref er t o t he an - 501 a p p li c a t i o n n o t e , a p er t u r e u n c er t a i n t y a n d a d c s y s t e m p e r f o r ma n ce , a nd t he an - 756 a p p l ic a t io n no t e , s a m p l e d s y s t e ms a n d t h e e f f e c t s o f cloc k p h a se n o i s e a n d ji t t e r , f o r m o r e i n f o r m a t i o n a b o u t j i t t er p er f o r m a n c e a s i t r e l a tes t o a d cs. p ow e r d iss ip a t io n a n d s ta ndb y m o de as sh o w n i n fi g u re 65 , t h e p o w er d i s si p a t e d b y t h e a d 9652 is p rop or t i on a l t o i t s s a m p l e r a t e . t h e da t a i n fi g u re 65 w as ta k en u si ng t h e s a me o p e r a t i ng c o nd it i o ns a s t ho s e u s e d f o r t he t y p i c a l p e r f o r m a n c e c ha r ac t e r i s t ic s s e c t i on . 1. 0 0. 9 0. 8 0. 7 0. 6 0. 5 0. 4 0. 3 0. 2 0. 1 2. 5 2. 0 1. 5 1. 0 0. 5 0 0 80 280 230 180 130 sa mpl e r a t e (msps) curre nt ( a) po w er (w ) 12169- 047 avdd3 avdd_clk drvdd/spivdd avdd pow er f i g u r e 65 . po w e r a nd c u rr en t vs . samp l e r a t e by a ss e r t i n g p ow e r - do w n ( e i t he r t hr o u g h s e t t i n g r eg i s t er 0 x 0 8 o r b y as s e r t in g t h e p d w n p i n hig h) , t he ad 9 652 is p l ac e d in p ow e r - d o w n mo de . i n t h i s s t a t e , t h e ad c t y p i c a l ly d i ss i p a t e s le s s t h a n 1 m w . d u r i ng p o wer - d o wn , t h e o u t p u t d r i v er s a r e p l ac e d in a hi g h im p e d an c e s t a t e . dea ss e r t i n g t h e pd w n p i n ( f orc i n g i t l ow ) r e t u r ns t he a d 9652 t o i t s n or m a l op e r a t i ng mo d e . n o t e t h a t t he le v e l o n p d w n i s r ef er en c e d t o t h e d i g i t a l o u t p ut d r i v e r sup p ly ( dr v dd ) an d c an no t e x c eed th a t s u p p l y v o l t a g e . l ow p ow e r d i s si p a t i o n i n p ow e r - do w n m o de i s a c h i e v e d b y sh ut t i n g d o w n t h e r ef er en c e , r ef er en c e b u f f er , b i a si n g n e tw o r k s, a nd c l o c k . i n t e r na l c a p a c i t o r s a r e di s c h a r g e d w h e n e n t e r i n g p ow e r - do w n mo de a n d t h e n m u s t b e r e c h a r g e d w h e n r e t u r n i n g t o n or m a l o p e r a t i o n . a s a r e s u l t , w a ke - u p t i m e i s r el a t e d t o t h e t i m e s p en t i n p ow e r - do w n m o de , a nd sho r t e r p o w e r - do w n c y c l e s r e s u l t i n p rop or t i on a l ly sh o r t er wa k e - up t i m e s . w h en u si n g t h e s p i p o r t i n t er f a c e , t h e u s er c a n p l a c e t h e ad c i n p ow e r - do w n m o de o r s t a ndb y m o d e . s t a ndb y m o d e a l l o w s t h e u s er t o k e ep t h e i n t er n a l r ef er en c e c i r c u i t r y p o w e r e d w h e n f a s t er w a k e - u p t i m e s a re re q u i re d . s e e t he an - 8 77 a p p l ic a t io n no t e , i n t e r f a ci n g t o h i gh s p e e d a d cs v i a s p i , f o r a ddi t i o na l d e t a i ls. in t e r n a l b a c k g r ou n d c a l ib r a t ion t he a d 9652 us e s a b a c k g r o un d ca l i b r a t i o n t o c o n t i n ua l l y co r r e c t e r r o r s b e t w e e n i n t e r n a l a n a l o g c ir c u i t s t o m ain t a in t h e hig h l e v e l o f no i s e p e r f o r m anc e o v e r v ar y i n g c o nd i t i o ns . t he c a l ib r a t i o n c or re c t i on d i g i t a l l y m on i t or s t h e e r ror s i n t h e v a r i ou s a n a l o g b lo c k s, c a lc u l a t e s t h e e r r o r , a n d a p p li e s c o r r e c t i o n s. t h e b a c k - g rou n d c or re c t i on i s c a l c u l a t e d e v e r y 3 2 33 s a m p le s; t h e r e f o r e , w h e n r un n i n g a t 310 ms p s, t h e u p d a t e r a t e i s a b o u t 83 s e co n d s . e a ch c a l i b r at i o n c y c l e i s i n d ep en d en t f r o m p r e vi o u s c a l i b r a t i o n s to i m p r o v e t r a c k i n g . t h er e a r e n o r e q u i r em en ts o n t h e i n p u t s i g n a l f o r t h e b ac kg r o u n d c a l ib r a t io n . t he c a l ib r a t io n o c c u r s i n d e p e n d e n t l y f o r e ac h a d c p a t h. t he b ac kg r o u n d c a l ib r a t io n c o n t in u a l l y o p e r a t e s b u t do e s n ot u p d a te i f t h e i n p u t si g n a l is s ig n if ic an t l y o u t o f r a n g e ( b e y o n d t h e o t r) b e c a u s e t his c a n c a u s e e r r o r s in t h e c a l ib r a t io n c a l c u l a t i on . t h e c a l i b r a t i on e n g i n e m on i t or s a n y e r ror s a n d rev. a | page 25 of 36
AD9652 data sheet r es et s t h e c a l i b r a t io n c y c l e if t he in p u t s ig n a l e x c e e d s t h e in pu t r a n g e f o r 1000 s a m p l e s w i t h i n a si n g le c a li b r a t i o n c y c le . a t s t ar t u p , w he n t he a d 9652 i s f i r s t p o w e r e d a nd a v a l i d c l o c k is a p p l ie d , a f a s t s t a r t - u p b ac kg r o u n d c a l ib r a t io n is p e r f o r m e d a nd c o n v e r g e s 6 4 t i m e s f a s t e r t h a n t h e n o r m a l c a li b r a t i o n c y c le . a t 310 ms p s, t h e fa s t s t a r t - u p c a l i b r at i o n u p d at e s af t e r 1 .3 s e c o n d s. t h e f a s t st a r t - u p c a li b r a t i o n a l lo w s t h e a d 9652 to b e u se d so o n e r t ha n wai t in g f o r a f u l l c a l ib r a t io n c y c l e a n d t y p i ca l l y d e gr a d e s s n r p e r f o r m a n c e b y les s t h a n 0 .5 d b . t h i s d e g r a d a t i o n la s t s u n t i l a f u l l c a l i b r a t i o n c y c le c o m p le t e s. i n c a s e s w h e re c on f i g u r a t i on of t h e a d 9652 c han g e s a n d a re c a l ib r a t io n is n e e d e d , a f as t s t a r t - u p ca l i b r a t i o n ca n b e i n i t i a t e d b y a n spi r e g i st e r w r i t e o r b y a ss e r t i n g a nd de as s e r t in g t h e p d w n p in . t o in i t ia t e u si n g t h e s p i r eg i s t er , u s e r eg i s t er 0 x 08[ 1: 0] . to s t a r t a n e w f as t c a l i b r at i o n , p u t ei t h e r o r bo th ad c c h a n n e l s i n s t a nd b y a nd t h e n r e t u r n t h e m t o n o r ma l o p e r a t i o n m o d e b y w r it i n g 0 x 2 a n d t h e n 0x 0 t o r e g i s t e r 0x 08 [ 1: 0] . af t er r et u r n i n g t o n o r m a l o p e r a t io n m o d e , t h e f as t c a l ib r a t io n i s in i t i a t e d o ne ti m e f o l l o w ed b y th e n or m a l , f u l l c a l i b r a t i o n c yc l e . i n a dd i t i o n t o s t an d b y, t his is a l s o t h e c as e f o r p o w e r - do w n. w r i t in g a 0 x 1 f o l l o w e d b y a 0x 0 i n i t i at e s a f as t c a l i b r a t io n . a l t e r n a t i vel y , a f a st s t ar t - u p c a l i b r a t i o n c a n b e i ni t i a t e d b y w r i t i ng 0 x 0 c a nd t h e n 0x 08 t o r eg i s ter 0 x 4 f b. th e p d w n p i n c a n b e c o nf i g u r e d t o p u t t h e d e v ic e i n p ow e r - d o w n o r s t andb y mo d e b a s e d o n t he s e t t i ng i n r e g i s t e r 0 x 0 8 [1 : 0 ] . t r a n s i t i on i n g f rom e i t h e r p ow e r - d ow n or s t a n d b y i n t o n or m a l m o d e c au s e s a f as t c a l ib r a t io n to b e in i t ia t e d . c o n f ig u r a t io n c h ang e s t h a t r e q u i r e a n e w c a l i b r a t i o n i n c l u d e , b u t a r e n o t l im i t e d t o , c ha n g e s o f s e t t i n g f o r v r e f , d i t h e r e n a b le / d i s a b l e , cl o ck i n p u t ch a n g e s , an d d c s st a t e c h a ng es. t he r e a r e v a r io u s ad v an c e d c o n f ig u r a t io n o p t i o n s as s o c ia t e d wi t h t he b ac kg r o u n d c a l ib r a t io n f o r a p p l ic a t io n s t ha t r e q u ir e s p ec i a l tr ea t m en t . t h e o p ti o n s i n c l u d e a n o p ti on a l re c o v e r y m o de f o r s t a ndb y an d a p a u s in g b ac kg r o u n d c a l ib r a t io n . i f s t a ndb y i s u s e d i n a n a p p l i c a t i o n, b y d e f a u l t , t h e a d 9652 ke e p s t h e c u r re n t c or re c t i on s , b u t i n i t i a t e s a n e w f as t c a l ib r a t i o n w h e n re t u r n i n g t o n or m a l op e r a t i on m o d e . f or s t a n d b y , i f c o n d i t io n s ha v e n o t s ig n if ic an t l y c ha n g e d , t h e a d 9652 c a n b e c o n f ig u r e d t o r e t a in t he l a s t c o r r e c t io n c o e f f ic ie n t s b y w r i t in g 0 x 0 0 t o reg i s ter 0 x 4 f a b ef o r e en t er i n g t h e s t a n d b y m o d e. t h i s r e tu r n s t h e d e vi c e t o t h e s a m e o p er a t i o n a s w h e n i t e n t er e d s ta n d b y , r e ta i n i n g p r evi o u s c a l i b r a ti o n v a l u e s i n s ta n d b y m o d e a nd c o n t i n u i ng t he no r m a l c a l i b r a t i o n c y c le w he n r e t u r ne d t o n or m a l op e r a t i on m o d e . a l t h o u g h t his is n o t r e c o m m e n d e d , in s o m e in s t an c e s s u c h as w h e n a l l t h e e n v i r o n m e n t a l, c lo c k i n g, a n d i n p u t si g n a ls a r e v e r y s t ab le , t he c a l i b r a t i o n c an b e p a u s e d. p a u si ng t he b a c k g rou n d ca l i b r a t i o n ca us e s a s l i g h t d e g r a d a t io n in p e r f o r m a n c e , b u t c an b e a c c o m p l i sh e d b y wr i t i n g 0 x 1 t o reg i st er 0 x 4 f b , b i t 0 . to r e - en a b le t h e b a c k g r o u n d c a l i b r a t i o n , w r i t e 0 x 0 t o reg i st er 0 x 4 f b , b it 0 . n o t e: reg i s t er 0 x 4 f b h a s r es er v e d b i t s t h a t m u st b e p r es er v e d w h en a c c es si n g t h a t an d s im i l a r r eg i st er s. d igi t a l ou t p u t s th e a d 9652 ou t p u t d r i v e rs a re f or s t an d ar d a n s i lv d s, bu t op t i on a l l y t h e d r i v e c u r r en t c a n b e r e d u c e d u si n g r eg i s t er 0 x 1 5 . th e r e d u c e d dr i v e c u r r en t f o r t h e lv d s o ut p ut s p o t e n t i a l l y r e d uce t h e d i g i t a l l y i n d uce d n o i s e . a s de t a il e d in t he an - 877 a p p li ca t i o n n o t e , i n t e r f a ci n g t o h i g h s p eed a d c s v i a s p i , t h e d at a f o r m at c a n b e s e le c t e d f o r o f f s et b i n a r y , t w o s c o m p le m e n t , o r g r a y c o d e w h e n u si n g t h e s p i c on t ro l . th e a d 9652 ha s a f l e x i b l e t hr e e - s t at e a b i l it y f o r t h e d i g it a l o u t p u t p in s . t he t hr e e - st a te m o d e is e na bl e d w h e n t h e d e vi c e i s s et f o r p o w er - do w n m o de . ti m i n g th e a d 9652 p r o vi d es l a t c h e d d a t a w i t h a p i p e l i n e d e l ay of 26 i n p u t s a m pl e cl o ck c y cl e s . d a t a o u t p u ts a r e a va i l a b l e o n e p rop a g a t i on d e l a y (t pd ) a f t e r t h e r i si n g e d g e o f t h e c lo c k si g n a l . m in im ize t he l e ng t h o f t he o u t p u t d a t a l i ne s and t h e c or re s p on d i n g l o a d s t o r e d u c e t r a n si en ts w i t h i n t h e a d 9652 . t h es e tr a n si en ts c a n de g r a de c o n ve r t e r dy n a m i c p e r f o r m anc e . t h e lo w es t ty p i c a l c o n v er si o n r a t e o f t h e a d 96 52 is 8 0 ms p s. a t c l o c k r a t es b e l o w 8 0 m s p s , dy n am i c p e r f o r m anc e m a y de g r a de . d at a c l o c k o ut p ut th e a d 9652 a l s o p r o vi d es a d a t a c l o c k o ut p ut ( d c o ) in t e n de d f o r c a p t u r in g t he d a t a i n a n e x t e r n a l r e g is t e r. fi g u r e 2 s h ow s a t im in g d i ag r am of t h e a d 965 2 o ut p ut m o d e s . t h e d c o r el a t i ve to t h e d at a o u t p u t c a n b e a d j u s t e d u s i n g reg i s t er 0 x 1 7 . t h er e a r e 3 2 d el a y s et t i n g s w i t h a p p r o x i m a tel y 8 1 p s p er s t e p. d a t a i s o ut p ut in a dd r f o r m at a nd i s a l i g ne d t o t h e r i si n g a nd f a l l i n g e dg e s o f t he c lo c k d e r i v e d f rom d c o . a dc o ve r r a n g e t h e ad c o v er r a n g e (o r ) i n di c a t o r i s a s s e r t e d w h e n a n o v er r a n g e i s d ete c t e d o n t h e i n p u t o f t h e ad c . t h e o v er r a n g e c o n d i t i o n i s d eter m i n e d a t t h e o u t p u t o f t h e a d c p i p e l i n e a n d , t h e re f or e, i s s u b j e c t t o a l a t e n c y o f 26 a d c c lo c k s. a n o v e r r a n g e a t t h e in p u t is i n d ic a t e d b y t his b i t , 26 cl o ck c y cl e s a f t e r it o cc ur s . rev. a | page 26 of 36
d ata she et ad 9652 ta bl e 13 . o ut p ut d at a f o r m at d iff er en t ia l i n p u t v o l t ag e ( v ): ( vi n + x ) C ( vi n C x) in pu t s pa n = 2 .5 v p - p ( v ) o ff set b in ar y o u t p u t m o de t w o s c o mp l em en t m o d e (d efau l t ) or p in l o g ic l e ve l < C 1.25 00 0000 0000 00 00 10 0000 0000 00 00 1 C 1.25 00 0000 0000 00 00 10 0000 0000 00 00 0 0 10 0000 0000 00 00 00 0000 0000 00 00 0 + 1.25 11 1111 1111 11 11 01 1111 1111 11 11 0 > + 1.25 11 1111 1111 1111 01 1111 1111 11 11 1 rev. a | p a ge 27 of 36
AD9652 data sheet f ast t h r esh o l d d et ec t io n (fd a /fd b ) i n r e c e i v e r a p p l i c a t io n s , i t is d e s ir a b l e t o h a v e a m e c han is m t o r e l i a b l y d eter m i n e w h en t h e c o n v er t er i s a b o u t t o b e c l i p p e d . th e s t a nda r d o v e r f l o w i ndi c a t o r on t h e o r pi n s p rov i d e de l a ye d i nf o r ma t i o n , w hic h is s y n c hr o n ize d w i t h t h e o u t p ut d at a . t h e d e l a ye d i ndi c a t o r is o f l im i t e d v a l u e in p r e v e n t in g c l i ppi n g in t his c as e . t h e r ef o r e, i t i s h el p f u l t o h a ve a p r o g r a m m a b l e t h r es h o l d b e l o w f u l l s c a l e t h a t a l l o ws t i m e t o r e d u c e ex t er n a l ga i n b e f o r e t h e c li p o c c u r s. i n a d d i t i o n , b e c a u s e i n p u t si g n a ls c a n h a v e si g n i f i c a n t s le w r a t e s, la t e n c y o f t h i s f u n c t i o n i s o f co n ce r n . u s i n g t h e s p i p o r t, t h e u s er c a n p r o vi d e a t h r es h o l d a b o ve w hic h t h e f a s t d et e c t ( fd ) o u t p u t i s a c t i ve. b i t 0 o f reg i s t er 0x 45 en a b l es t h e fd f e a t u r e. r e g i s t e r 0 x 4 7 t o reg i s ter 0 x 4 c a l l o w t h e u s er t o s et t h e t h r es h o l d l e v e l s a nd t i m i ng . a s l o n g a s t h e si g n a l i s b e lo w t h e s e le c t e d t h r e sh o ld , t h e f d o u t p u t r e m a i n s lo w . i n t his m o d e , t h e m a g n i t u d e o f t he d a t a is c o n s i d e r e d i n t h e c a l c u - l a t i o n o f t h e c o ndi t i o n, b u t t h e s i g n o f t h e d at a ( ei t h er p o s i t i v e o r n e g at i ve ) i s n ot c on s i d e re d . the t h r e s ho l d d e t e c t i o n r e s p o nd s i d en t i c a l l y t o p o s i t i v e a n d n eg a t i v e s i g n a l s o u ts i d e t h e d es i r e d r ang e ( m ag n i t u d e ) . th e f a s t d ete c t i n d i c at o r s, f da f or c h a nn e l a a nd f db f or c h a nne l b , a re a s s e r t e d w he n t h e i n p u t m a g n i t u d e ex c e e d s t h e va l u e p r o g r a m m e d i n t h e f a s t d et e c t u p p er t h r es h ol d re g i s t e r , reg i st er 0 x 4 7 . t h e s e le c t e d t h r es h o l d r eg i s t er i s c o m p a r e d wi t h t h e s i g n a l m a g n i t u d e a t t h e o u t p u t o f t h e ad c . t h e f a s t u p p er t h re s h o l d d e t e c t io n has a l a t e n c y o f s e v e n c lo c k c y c le s. t h e a p p r o x im a t e u p p e r t hr e s h o l d is a 4- b i t v a l u e d e f i n e d by u ppe r t h re s h o l d ( % f u l l s ca le ) = (( r eg is t er 0x 47 v a lu e ) /8 ) 100 % t h e f d i n d i c a to r s a r e n o t c l e a r e d u n t i l t h e si g n a l d r o p s b e lo w t h e lo w er t h r es h o l d f o r t h e p r o g r a m m e d d we l l t i m e . t h e lo w er th r e s h o l d i s p r o g r a m m e d i n t h e f a s t d et ec t l o w er th r e s h o l d r eg i s t er s, r eg i s ter 0 x 4 9 a n d reg i s t er 0 x 4 a. t h e f a s t d e t e c t lo w e r t hr e s h o l d r e g is t e r is a 1 5 - b i t r eg i s t er t h a t i s c o m p a r ed wi th th e s ig n a l m a g n i t u d e a t t h e o u t p u t o f t h e a d c . t h is c o m p a r is o n is s u b j e c t t o t h e a d c p i p e l i n e l a ten c y b u t i s a c c u r a t e i n t er m s o f c o n v er t er r es o l u t i o n . t h e lo w er t h r es h o l d i s d ef i n e d b y l ow e r th r e sh ol d ( % fu ll s ca le ) = (( r eg is t er 0x 4 9 / r eg is t er 0x 4a v al u e )/3276 7 ) 100 % f o r ex a m p le , t o s et a n u p p er t h r es h o l d o f 5 0 % f u l l s c a le , wr i t e 0x 0 4 t o reg i s ter 0x 4 7 , and t o s e t a l o w e r t h r e sho l d o f 40% f ul l s c a le , wr i t e 0 x 3 333 t o r eg i st er 0x 49 a n d reg i s ter 0x 4a . t h e dw e l l t i m e c an b e p r o g r am me d f r o m 1 s a m pl e cl o ck c y cl e t o 6 5 ,5 3 5 s a m p l e c lo c k c y c le s b y p la c i n g t h e d e si r e d va l u e i n t h e f a s t d e t e c t d w e l l t i m e r eg i s t er s, reg i st er 0 x 4 b a n d r eg i s t er 0 x 4 c ( s e e fi g u r e 66 ) . upper threshold lower threshold f da o r f db m i ds cal e d we ll tim e t i mer r eset b y ri s e abo v e lowe r t hre s ho l d t i mer c o mpl et es b ef o r e s i g nal ri s e s abo v e lowe r th r e s h old dwell time 12169-048 figure 66 . thre shold settings for f da a nd f d b si g n a l s rev. a | page 28 of 36
d ata she et ad 9652 ser ial p o r t in t e r f ac e th e a d 9652 s e r i a l p o r t i n t er f a c e ( s p i ) a l l o w s t h e u s er t o c on f i g u re t h e c on v e r t e r f or s p e c i f i c f u n c t i o n s or op e r a t i on s t hr o u g h a s t r u c t u r e d r e g i s t e r s p a c e p r o v i de d i ns i de t h e a d c . t h e s p i g i v es t h e u s er a d d e d f l ex i b i l i ty a n d c u s to m i z a t i o n , de p e ndi n g o n t h e a p p l i c a t i o n. a ddr e s s e s a r e a c c e s s e d v i a t h e s er i a l p o r t a n d c a n b e wr i t t e n to o r r e a d f r o m v i a t h e p o r t. m e m o r y is o r g a n i ze d in t o b y t e s t ha t c an b e f u r t h e r d i v i de d i n t o f i e ld s. t h e s e f i e l d s ar e d o c u me n t e d i n t he m e m o r y ma p s ec ti o n . f o r d et a i l ed o p e r a ti o n a l i n f o r m a ti o n , s ee t he an - 877 a p p l ic a t io n n o te , i n t e r f a ci n g t o h i gh s p e e d a d cs v i a s p i . c on f ig u r a t io n u s in g th e s pi t h r e e p i n s d ef i n e t h e s p i o f t h i s ad c : t he s c l k pi n , t he sd io pi n , a nd t he c sb pi n (s e e ta b l e 14 ) . t h e s c lk ( s e r ia l c l o c k) pi n is u s e d t o s y n c h r o n ize t he r e a d a nd w r i t e d at a p re s e n t e d f rom / t o t h e ad c. t h e s d io ( s er i a l d a t a i n p ut / o ut p ut ) pi n is a d u a l - pu r p o s e pi n t h a t a l l o ws d a t a t o b e s en t a n d r e a d f r o m t h e i n t e r n a l ad c m e m o r y m a p r eg i s t er s . t h e c sb ( c h i p s el e c t b a r ) pi n is an a c t i v e l o w c o n t r o l t h a t en a b l es o r d i s ab l es t h e r e a d a n d w r i t e c y c le s. ta bl e 14 . s e r ial po r t in t e r f ace pin s pin function scl k s er ia l c l o c k . t h e s er ia l s h if t cl o ck in p u t , w h ich is u s ed t o s y n ch r o n iz e s er ia l in t er f a c e r ea d s an d w r it es . s dio serial data input/out put . a dual - purpose pin that typically serves as an input or an output, depending on the instruction being sent and the relative position in the timing frame. csb c hi p s e l e c t bar . a n ac t i v e lo w c o n t r o l t h a t g a t e s t h e r e a d a n d w r it e c y cl es . m u st b e p u lle d t o l og i c hi g h d u r i ng pow e r u p . th e f a l l i n g e dg e o f c sb , in c o n j u n c t io n w i t h t he r is in g e d g e o f s c lk , d et er m i n es t h e s t a r t o f t h e f r a m i n g . a n ex a m p l e o f t h e s e r ia l t im in g an d i t s d e f in i t io n s c a n b e f o u n d in ta b l e 5 a nd fi g u r e 4 . o t h er m o d es i n v o l vi n g t h e c sb pi n ar e a v ai l ab l e . t he c sb pi n c a n b e h e l d l o w i n d ef i n i te l y , w h i c h p er m a n e n t l y en a b l es t h e d e v ic e ; t his is c a l l e d s t r e a m in g . t he c sb pi n c an s t a l l h ig h b e tw e e n b y t es to a l l o w f o r a d d i t i o n a l ex t er n a l t i m i ng . whe n c sb is t ie d hig h , s p i f u n c t io n s a r e p l ac e d in a hig h im p e d an c e mo d e . d u r in g a n in s t r u c t io n p has e , a 1 6 - b i t in s t r u c t io n is t r a n s m i t t e d . d a t a f o l l o w s t he in s t r u c t io n p h as e , an d i t s l e n g t h is d e t e r m i n e d by t h e w 0 a nd t h e w 1 b it s. a l l d a t a is c o mp o s e d o f 8 - b i t wo r d s. t h e f i r s t b i t o f e a c h in d iv i d u a l b y t e of s e r ia l d a t a i n d ic a t e s w h e t h e r a r e ad or wr i t e c o m m an d is is s u e d . t his a l l o ws t h e s e r i a l d a t a i n p u t /o u t p u t ( s d i o ) p in t o c ha n g e d ir e c t io n f r o m a n in p u t to a n o u t p u t . i n a dd i t i o n t o w o r d l e n g t h, t he i n s t r u c t io n p has e d e t e r m i n e s w h et h er t h e s er i a l f r a m e i s a r e a d o r wr i t e o p er a t i o n , a l l o w i n g t h e s er i a l p o r t to b e u s e d b o t h to p r o g r a m t h e c h i p a n d t o r e a d t h e c o n t en ts o f th e o n - c h i p me mo r y . i f t he i ns t r u c t i o n i s a r e a db ac k o p e r a t io n , p e r f o r m in g a r e ad b ac k c a u s e s t h e s e r ia l d a t a in p u t / o ut p ut ( sd io /d c s ) p in t o c ha n g e d ir e c t io n f r o m a n in p u t t o a n o ut p ut a t t h e a p p r o p r i a te p o i n t i n t h e s er i a l f r a m e . d a t a c an b e s e n t in m s b f ir s t m o d e o r in ls b f i r s t m o d e . m sb f i r s t i s t h e d ef a u l t o n p o w er - u p a nd c a n b e c h a ng e d v i a t h e s p i p or t c on f i g u r a t i on re g i s t e r . f or m ore i n f or m a t i on a b o u t t h i s a n d o t h er f e a t u r es , s e e t he an - 877 a p p li ca t i o n n o t e . h a rd wa re i n t e rfa c e th e p i ns de s c r i b e d i n ta b l e 14 c o m p ri se t h e p h y s ic a l in t e r f ac e b e tw e e n t h e u s e r p r o g r a m m i n g d e vi c e a n d t h e s er i a l p o r t o f t h e a d 9652 . t he s c lk p i n an d t he c sb pi n f u n c t i o n a s i n pu t s w h e n u si n g t he s p i in t e r f ac e . t h e s d i o p i n is b id ir e c t io n a l , f u n c t io n in g as an i n p u t d u r in g wr i t e p has e s an d as a n o u t p u t du r i n g r e a d b ac k. t h e s p i i n ter f a c e i s f lex i b le e n o u g h to b e c o n t r o l l ed b y ei t h er f i el d - p r o g r am m ab l e g r i d a r r ay s ( f pga s) or m i c r o c o n t r o lle r s. on e m e t ho d f o r s p i c o n f ig u r at io n is d e sc r i be d in d e t ail i n t he an - 812 a p p l ic at io n n o t e , m i c r ocon t r o ll e r - b a s e d s e r i a l p or t i n t e r f a ce ( s p i ) b oot ci r cu i t . t h e s p i p o r t mu s t n o t b e a c t i ve d u r i n g p er i o d s w h en t h e f u l l d y n a m ic p e r f o r m a n c e o f t he c o n v e r t e r is r e q u ir e d . b e c a u s e t he s c lk si g n a l , t h e c sb s ig n a l , an d t h e s d i o s ig n a l a r e ty p ic a l l y as y n c hr o n o u s to t h e a d c c l o c k, n o is e f r o m t he s e s ig n a l s c an d eg r a d e c o n v er ter p er f o r m a n c e . if t h e o n - b o a r d s p i b us i s us e d f or ot h er d e vi c es , i t m a y b e n e c es s a r y t o p r o vi d e b u f f e r s b etw e en t his b u s an d t h e a d 9652 t o pr e v en t t h es e si g n a ls f r o m t r a n s i - t i o n i n g a t t h e c o n v er t er i n p u ts d u r i n g c r i t i c a l s a m p li n g p e r i o d s. c on f igu r a t io n w it h o u t t he s p i i n a p p li c a t i o n s t h a t d o n o t i n ter f a c e t o t h e s p i c o n t r o l r eg i s t e r s, t h e sd io pi n and t h e s c lk pi n s e r v e a s s t a n d a lo n e cm os - co m p a t i b le c o n t r o l p i n s. w h e n t h e d e v i c e i s p o w e r e d u p , i t i s a ssu m e d t h a t t h e u s er i n t e n d s to u s e t h e p i n s a s s t a t i c c o n t r o l l i ne s f o r t he d cs a nd ou t p u t d a t a f or m a t f e a t u re c on t ro l . i n t h i s mo d e , c on n e c t c sb t o a v d d , w hic h d i s a b l es t h e s er i a l p o r t i n t e r f a c e. ta bl e 15. m o d e s elec t i on pi n ex t er n al vo l t a g e c o n fig u r a t io n s dio a v dd ( d e fa u l t ) d cs e nabl e d ag n d dcs di s a ble d sclk avdd twos compl e ment enabled a gn d ( d e fa u l t ) o f f s e t bi nar y e nabled re v . a | page 29 of 36
AD9652 data sheet sp i a ccessi b l e f ea t u r es ta b l e 16 p r o v id e s a b r ie f d e s c r i p t io n o f t h e g e n er a l f e a t u r es t h a t a r e a c c es s i b l e vi a t h e s p i . t h es e f e a t u r es a r e d es c r i b e d i n d et a i l i n t he an - 877 a p p l i ca t i o n n o t e . ta bl e 16 . fe a tu r e s ac c e ssi b l e u si n g th e s p i fe a t u r e n am e d esc r ip t io n power mode s allows the user to set either power - down mode or standby mode clock allows the user to access the dcs via the spi offset allows the user to digitally adjust the converter offset test i/o allows the user to set test modes to have known data on output bits output mode allows the user to set up outputs output phase allows the user to set the output clock polarity output delay allows the user to vary the delay of the clock derived from dco vref allows the user to set the reference voltage rev. a | page 30 of 36
d ata she et ad 9652 me mo r y ma p r e a d in g t h e m e m or y m a p re g i s t e r t a b le e ac h r o w i n t h e m e m o r y m a p r e g is t e r t ab l e has e ig h t b i t l o c a t i o ns . t he me mo r y m a p i s r o u g h l y d iv i d e d i n t o th r ee s e c t io n s : t he c hi p c o n f ig u r a t io n r e g is t e r s ( a d d r e s s 0 x 0 0 t o a d d r e s s 0x 02) ; t he c h an ne l i nd e x and t r a ns f er r eg i s t er s ( a ddr e s s 0 x 0 5 a nd a d d r e s s 0 xff) ; a nd t he a d c f u nc t i o ns r e g i s t e r s, i n c l u d i n g s e t u p , c o n t r o l , a n d t e s t ( a d d r e s s 0x 08 t o a ddr e s s 0x 4f b ). t he m e m o r y m a p r e g is t e r t ab l e ( s e e ta b l e 17 ) d o c u me n ts t h e d e f a u l t he x ad e c im a l v a l u e f o r e ac h h e x ad e c im a l a d d r e s s sh o w n . t h e c o l u m n w i t h t h e h e a d i n g b i t 7 ( m s b ) i s t h e s t a r t o f t h e d ef a u l t h ex a d e c i m a l v a l u e g i v e n . f o r ex a m p l e , a d d r es s 0 x 09 , t he g lo b a l c lo c k r e g is t e r , has a h ex a d e c i m a l d ef a u l t va l u e o f 0x 0 1 . t his me a ns t h a t t he lsb or b it 0 = 1 , and t h e r e m ainin g b i ts a r e 0 s . t his s e t t in g is t he d e f a u l t ou t p u t f or m a t v a l u e , w hic h is t wo s c o m p l e m e nt . f or m ore i n f or m a t i on o n t he f u nc t i o ns co n t r o l l e d b y r e g i s t e r 0x 00 t o reg i st er 0 x 1 7 , s e e t he an - 877 a p p l i c a t i on n ot e . t his ap p l i c at i o n n o t e a ls o d e t ai l s t he f u n c ti o n s c o n tr o l l ed b y a l l r em a i n i n g r eg i s t er s . o p en an d r e s e r ve d loc a t io ns al l a d d r es s a n d b i t lo c a t i o n s t h a t a r e n o t i n c l u d e d i n ta b l e 17 a re n ot c u r re n t l y s u p p or t e d f or t h i s d e v i c e . u n u s e d b i t s of a v a li d a d dr e s s l o c a t i o n m u st b e wr i t t e n w i t h 0 s , u n l es s o t h er wi s e n ot e d . w r i t i n g t o t h e s e lo c a t i o n s i s r e q u i r e d o n ly w h e n p a r t o f a n a d d re s s l o c a t i on i s op e n ( f or e x a m p l e , a d d re s s 0x 18) . i f t h e e n t i re a d d re s s l o c a t i o n i s op e n / u n u s ed / u n d o c u m en t e d (f o r e x a m p le , a d d r e s s 0 x 1 3 ) , t h i s a d d r e s s lo c a t i o n m u s t n o t b e w r i tt e n . d e f a u l t v a l u e s af t er t h e ad9 6 5 2 i s r es et, c r i t i c a l r e g is t e r s a r e l o ad e d w i t h d ef a u l t va l u es . t h e d ef a u l t v a l u es f o r t h e r eg i s ter s a r e g i v en i n t he m e mo r y m a p r e g i s t e r t ab le , ta b l e 17 . log ic le v e ls a n ex p la n a t i o n o f lo g i c le v e l t e r m i n o lo g y f o l lo w s: ? b i t i s s e t i s sy n o n y m o u s w i t h b i t is s e t t o l o g ic 1 o r wr i t i n g l o g i c 1 f o r t h e b i t. ? c l e a r a b i t is s y n o n y m o u s w i t h b i t is s e t t o l o g ic 0 o r wr i t i n g l o g i c 0 f o r t h e b i t. tr a n s f e r r e gi s te r m a p th e 0x 08, 0x 09, 0x 0b , 0x 0d , 0x 0f , 0x 10, 0x 14, 0x 16, 0x 17, a n d 0x 30 r eg i s t er s a re s h a d o we d . w r i t es t o t h es e a d d r es s es d o n o t af f e c t de v i c e o p e r a t io n u n t i l a t r a n s f e r c o m m a n d i s i ssue d b y w r i t i n g 0 x 0 1 t o a d d r e s s 0 x f f , s e t t i n g t h e t r a n s f e r b i t . t h i s a l lo w s t h es e r eg i s t er s to b e u p d a t e d i n t er n a l l y a n d s i m u lt a n e o u s l y wh en t h e t r a n sf er b i t i s s et. t h e i n t er n a l u p d a t e o cc ur s w h en t h e t r ans f e r b i t i s s e t , a nd t he n t he b i t a u t o c l e ar s. c ha nn e l sp e c i f i c r e gi s te r s s o me c h an ne l s e t u p f u nc t i o ns , s u c h a s t he s i g n a l mo n i t o r t h r e s ho l d s, c an b e p r o g r am m e d t o a d i f f er en t v a l u e fo r e a ch c h a nne l . i n t h e s e c a s e s , c han n e l ad d r e s s l o c a t io n s a r e in t e r n a l l y d u p li c a t e d f o r e a c h c h a n n e l . t h e se r e gi s t e r s a n d b i t s a r e d e si g n a t e d i n ta b l e 17 a s l o c a l . t he s e l o c a l r e g i s t e r s and b i t s c an b e ac c e s s e d b y s e t t i n g t h e a p p r o p r ia t e c han n e l a o r c ha n ne l b b i t s i n reg i st er 0 x 0 5 . i f b o t h b i ts a r e s e t, t h e su b s e q u en t w r i t e a f f e c ts t h e r e g i s t e r s o f b o t h c h a n n e ls. i n a r e a d c y c le , o n l y c h a n n e l a o r c h a nne l b a re s et t o r e a d o n e o f t h e tw o r eg i s t er s. i f b o t h b i t s a r e s et d u r i n g a n s p i r e a d c y c l e , t h e de v i c e r et u r n s t h e va l u e f o r c h a nne l a . r e g i s t e r s a n d b i t s d e si g n a t e d a s g lo b a l i n ta b l e 17 a f f e c t t h e en t i r e de v i c e a nd t he c h an ne l f e a t u r e s f o r w h i c h i n d ep en d en t s et t i n g s a r e n o t a l l o w e d . th e s e t t in g s in r e g is t e r 0 x 0 5 d o n o t a f f ec t t h e g l o b a l r eg i s t er s a n d b i t s . rev. a | page 31 of 36
AD9652 data sheet memo r y m a p r e gi st e r t a ble al l a d d r es s a n d b i t l o c a t i o n s t h a t a r e n o t i n c l u d e d i n ta b l e 17 a re n ot c u r re n t l y s u p p or t e d f or t h i s d e v i c e . ta bl e 17 . m em or y m a p r eg i s t er s addr ( h ex ) r eg i s t er n a me b i t 7 ( m s b ) bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 b i t 0 ( l s b ) d ef au l t v al u e ( h ex ) d ef au l t note s/ c o mme n t s chip configuration registers 0x 00 s p i p or t c o nfi g - u r at io n ( glo b a l) 1 0 lsb first soft reset 1 1 soft reset lsb first 0 0x18 the nibbles are mirrored so that lsb first mode or msb first mode registers correctly, regardless of shift mode 0x 01 ch ip i d ( glo b a l) 8 - b it c hip id[7:0] , ( AD9652 = 0x c1 ) (default) 0x c1 read only 0x 02 ch ip g r ad e ( glo b a l) sp eed g r a d e i d , 0x 00 : d e f a u lt 0 x 00 sp eed g r a de i d u s e d to dif f e r - e n ti at e dev i ces ; r e a d on l y channel index and transfer registers 0x 05 c ha nne l i n d ex ( glo b a l) c ha nn e l b ( de f au l t) c ha nne l a ( de f a u l t) 0x 03 bit s a r e s e t to det er m i n e whi c h de vi c e on t h e ch i p r ecei v es t h e n ext w r i te c om m an d; a p p l i es t o lo c a l r eg i s t er s on ly 0x f f tr an s f e r ( glo b a l) transf e r 0x 00 syn ch r o - n o u s l y t r a n s f er s da ta f r om t h e m a s t er s h i f t r e g i s te r to th e s l av e a d c functions 0x 08 p o w e r m ode s ( lo c a l ) r e ser v ed , s e t to 1 ex t e r n a l p o w er - d o w n p i n fu nc t i o n (l o c a l) 0 = po w er - dow n 1 = s ta n db y int e r na l p o w e r - d ow n m ode ( lo c a l) 00 = n o r m a l op e r a ti on 01 = f u l l p o w e r - do wn 10 = s t a n db y 1 1 = r es er v ed 0x 8 0 c on tr ol s p ow e r - d o wn o p ti on s 0x 09 g l o b a l cl o ck ( glo b a l) enable d cs ( de f a u l t) 0x 01 re v . a | p a ge 32 of 36
d ata she et ad 9652 addr ( h ex ) r eg i s t er n a me b i t 7 ( m s b ) bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 b i t 0 ( l s b ) d ef au l t v al u e ( h ex ) d ef au l t note s/ c o mme n t s 0x 0b c l oc k di vi de ( glo b a l) cl o c k div id e r at io 000 = d i v i d e b y 1 001 = d i v i d e b y 2 010 = r e s e r v e d , d o n o t us e 011 = d i v i d e b y 4 100 = d i v i d e b y 8 0x 00 0x 0d t e s t mode ( lo c a l) r eset p n 23 l o n g ge n p n 23: 1 + x 17 + x 22 res et pn 9 s h or t g e n p n9 : 1 + x 3 + x 8 o u tp u t te s t m ode 000 0 = of f ( de f a u l t ) 000 1 = m i ds c a l e s h or t 001 0 = p os i ti v e f s 001 1 = n e g a ti v e f s 0 1 0 0 = al te r n ati n g c h e c k e r b oar d 010 1 = p n 23 l on g s eq u en ce 011 0 = p n 9 s h o r t s eq u en ce 0 1 1 1 = on e / z e r o w or d tog g l e 0x 00 w he n this r eg i s t er i s s et , t h e t es t dat a is p l a ced on th e out p ut p i n s ( d 0 t o d 15 ) in p l ac e of n or m al data 0x 0f c om m on - m ode s e rv o ( glo b a l) enable common - mode s er v o 0x 00 0x 10 of f s et a dj u s t ( lo c a l) offset adjust in l sb s f r o m + 1 2 7 ( 011 1 11 11) t o ? 12 8 ( 1 000 00 00) ( tw os c om p l e m e n t f or m a t) 0x 00 0x 14 o ut p ut m ode ( lo c a l) o ut p ut f o r m a t 00 = o f f s e t b i n a r y ( de f a u l t) 0 1 = tw os c om p l e m e n t 10 = g r a y c ode 1 1 = r es er v ed 0x 00 co n f ig u r e s th e ou tp u ts a n d th e fo r ma t of th e da ta 0x 15 o ut p ut l v ds c on tr ol ( glo b a l) lvds output drive current a d jus t 000 = 3. 72 m a ( a n si - l v ds, d e f a u lt ) 001 = 3. 50 m a 010 = 3. 30 m a 011 = 2. 96 m a 100 = 2. 82 m a 101 = 2. 57 m a 110 = 2. 27 m a 111 = 2. 00 m a ( r e d u ced s w i n g l v ds) 0x 00 0x 16 c lo c k p h a s e a d jus t ( glo b a l) input clock divider p h a s e a d j u s t 000 = n o d e la y 001 = 1 i n p ut c l o c k cycl e 010 = 2 i n p u t cl o c k cycl e 011 = 3 i n p u t cloc k cycl e 100 = 4 i n p u t cloc k cycl e 101 = 5 i n p u t cloc k cycl e 110 = 6 i n p u t cloc k cycl e 111 = 7 i n p u t cloc k cycl e 0x 00 0x 17 d co out p ut dela y ( glo b a l) dco cl o ck de la y (d ela y = ( 2 500 p s r e g i s t er v a l ue / 3 1) ) 000 00 = 0 p s 000 01 = 81 p s 000 10 = 1 61 p s 111 10 = 24 19 p s 111 11 = 25 00 p s 0x 00 0x 18 i n p ut s p an s el ect ( glo b a l) r e ser v e d , s e t to 1 res er v ed , s e t to 1 v r ef se l e c t 000 = 1. 25 v ( 2. 5 v p - p i n pu t ) , d e f a ul t 001 = 1. 125 v ( 2 . 25 v p - p i n pu t ) 010 = 1. 20 v ( 2. 4 v p - p i n pu t ) 011 = 1. 25 v ( 2. 5 v p - p i n pu t ) 100 = d o n ot u s e 101 = 1. 0 v ( 2. 0 v p - p in p u t) 0x c 0 0x30 dither (local) di t h er e n a b le 0x 00 re v . a | page 33 of 36
AD9652 data sheet addr (hex) r eg i s t er n a me b i t 7 ( m s b ) bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 b i t 0 ( l s b ) d ef au l t v al u e ( h ex ) d ef au l t note s/ c o mme n t s 0x 45 f a s t de te c t ( f d ) c on tr ol en a b le f as t de te c t o ut p ut 0x 00 0x 47 fd u p p er th r e s h ol d f as t det ect u p p er t h r es h ol d [ 3: 0] v al i d p r o g r am m in g r an g e = 0 x 1 to 0 x 8 t h r es h ol d = m i ds ca l e ( r eg i s t e r v a l u e) ( 1/ 8) (f u ll s c a le ) 0x 0 8 0x49 fd l o w e r th r e s h ol d f as t det ect l ow er t h r es h ol d [ 7: 0] 0x 00 0x 4a fd l o w e r th r e s h ol d f as t det ect l ow er t h r es h ol d [1 4 : 8] 0x 0 2 0x 4b fd d w e ll t im e f as t det ect dw ell t i m e [ 7: 0] 0x 00 0x 4c fd d w e ll t im e f as t det ect dw ell t i m e [ 15: 8] 0x 0 8 0x 100 s yn c c on tr ol ( glo b a l) c lo c k di vi de r n e xt sy n c on ly c lo c k di vi de r sy nc en a bl e m a s t er sy nc b u ffe r en a b l e 0x 00 0x 212 d it h er gain ( glo b a l) 0b 000 0 : 10 0 % di t h er a p p l i ed 0b 000 1: 99. 6 % di t h e r a p p l i ed 0b 001 0: 99. 2 % di t h er a p p l i ed 0b 001 1: 98. 4 % di t h e r a p p l i e d 0b 010 0: 96. 8 % di t h e r a p p l i e d 0b 010 1: 93. 7 5% di th e r a p p l i e d 0b 011 0: 87. 5 % di t h e r a p p l i e d 0b 011 1: 75 % di th e r a p p l i e d 0b 100 0 : 5 0 % di t h er a p p l i ed res er ved , s e t to 0 res er ved , s e t to 0 res er ve d, s e t to 0 res er ved , s e t to 0 0x 08 0x22a in p ut f r eq u en cy s e tti n g s ( glo b a l) 0: f in in 1 st n yq u i s t 1: f in in 2 nd n yq u i s t 2: f in i n 3 rd n y q u i s t or hig he r 0x 00 0x 4f a cal ib r at io n p o w er - dow n c o nfi g - u r at io n ( glo b a l) r e ser v ed , s e t to 0 res er v ed , s e t to 0 res er ved , s e t to 0 r e ser v ed , s e t to 0 res er ved , s e t to 0 res er ved , s e t to 0 p ow e r dow n / s t a n db y in it ial c al ib r at i on ac tio n : 0b 00 : u s e p r ev i ou s ca l i b r a t i on co r r ect i o n 0b 11 : in it iat e a f as t c al ib r a t io n 0x 03 0x4fb calibration power - down configura - tion (global) r e ser v ed , s e t to 0 res er v ed , s e t to 0 res er ved , s e t to 0 r e ser v ed , s e t to 0 res er ved , s e t to 1 res et b ac k - gr o un d c al ib r ati o n , s e t hig h th e n l ow res er ved , s e t to 0 p a u s e b a ck - g ro u n d c a l i b r ati o n 0x 0 8 1 set t he c ha nne l i nd e x r e g i s te r a t a d d r e s s 0 x 0 5 to 0 x 0 3 ( d e f a u l t) w he n w r i ti ng to a d d r e s s 0 x 0 0 . rev. a | page 34 of 36
d ata she et ad 9652 a ppl i ca t i ons i nf orm a t i o n d e s ig n g u i d e l ine s b e f ore s t a r t i n g s y s t e m le v e l de s i g n a nd l a yo u t o f t h e a d 9652 , it is r e c o m m e n d e d t ha t t h e d e s ig n e r b e c o m e f am i l ia r wi t h t h e s e g u i d e l i ne s , w hic h d es c r i b es t h e s p e ci a l c i r cui t co n n e ct i o n s a n d l a y o u t r e q u i r em en ts n e e d e d f o r c er t a i n p i n s . pow e r a n d gr ou n d re c om m e n d a t ion s whe n c o n ne c t i ng p o w e r t o t he a d 9652 , i t i s r e c o mm e nde d t h at t h re e s e p a r at e p o wer s u p p l i es b e u s e d . a vd d 3 r e q u i r e s a 3 .3 v s up pl y , a v d d _ c l k and a v d d r e q u ir e a 1. 8 v s up pl y , and d r vd d r e q u i r e s a 1 .8 v s up pl y . s p i vd d i s t y p i c a l l y c o n n e c t e d t o t h e s ame s u p p l y a s d r v d d , b u t c an b e c o n ne c t e d t o a s e p a r a t e s u p p l y b et w e en 1 . 8 v and 3 . 3 v t o e a s e t he i n t e r f ac e t o t he l o g ic de v ic e t ha t c o nn e c t s to t he s p i p ins ( c l k , s d i o , and c sb ) . t h e a vdd 3 su p p l y mu s t b e s u p p l ie d f r o m a c l e an 3 . 3 v p o w e r s o ur c e . d e co u p l i n g mu s t b e a c o m b in a t i o n o f p c b p l ane c a p a c i t anc e and de c o u p l ing c a p a c i t o r s t o c o v e r b o t h hi g h and l o w f r e q u e n c y n o i s e s o ur ce s . t y p i ca l c a p a ci t o r s o f 0. 1 f and 1 f ne a r t he a d 9652 a vdd 3 p i n s a r e a d v i se d . t h e a vd d a n d a vdd _ c lk su p p l y c o n n e c t i o n m u s t b e p ow e r e d u p si m ul t a n e o u s l y to a c h i e v e p r op e r on - c h ip bi a s i n g ; t h er ef o r e, i t i s r e c o m m e n d e d to c o n n e c t t h e t w o su p p ly v o lt a ge s t o a s i n g l e s o u r c e . s im i l a r t o t he a v d d 3 s u p p l y , de c o u p l ing mu s t b e a c o m b in a t io n o f p c b p l ane c a p a c i t anc e and de c o u p l ing c a p a c i t o r s t o c o v e r b o t h h ig h and l o w f r e q u e n c y n o is e s o u r c e s . t y p i ca l ca p a ci t o r s o f 0 . 1 f and 1 f ne ar t he a d 9652 a vd d and a v d d _ c l k p i n s is a dv i s e d . th e d r v d d a nd s p i v d d s u p p l y c o nn e c t i o n mu s t a l s o h av e d e c o u p li n g b u t t h es e c a n b e p l a c e d s l i g ht l y f u r t h e r aw a y f rom t he a d 9652 . dr v dd a n d s p i v dd c a n b e t i e d t o g et h er f o r a p p li c a t i o n s t h a t c a n u s e a 1 .8 v s p i i n t e r f a c e lo g i c . o p t i o n a l ly , sp i v d d c a n b e d r i v e n w i t h a s up p l y o f up t o 3 . 3 v t o s up p o r t hig h e r v o l t a g e l o g ic in t e r f ac e s . m u l t ip l e l a r g e ar e a p c b g rou n d p lane s ar e r e c o m m e nde d a n d p r o vi d e m a n y b en ef i t s. l o w i m p e da n c e p o w e r a nd g r o u nd p l ane s ar e ne e d e d t o m a i n t ain p e r f o r m a n c e . s t ac k in g p o w e r a nd g r o u nd p la n e s i n t h e p c b p r o v i de s hig h f r e q u e n c y de c o u p li ng . g r o u nd p l a n e s a nd t h e r ma l v i a s h e l p d i s s i p at e h e at g en er a t e d b y t h e d e vi c e . w i t h p r o p e r de c o u p l i ng a nd s ma r t p a r t i t i o n i n g o f t h e p cb a n a lo g, d i g i t a l , a n d c lo c k s e c t i o n s, o p t im u m p e r f o r m a n c e is e as i l y ac hie v e d . v cm t h e vc m pi n m u s t b e d e co u pl e d t o g r o un d w i t h a 0. 1 f c a p ac i t o r , as s ho w n i n fi g u r e 54 . f o r o p t im a l c ha n n e l - t o - c h a n ne l is o l a t io n , a 3 3 ? r e s is t o r mu s t b e i n c l u d e d b etw e en t h e ad9 6 5 2 v c m p i n an d t h e c han n e l a an a l o g in p u t n e t w o r k c o n n e c t io n , as w e l l as b e tw e en t h e a d 9652 v c m p i n a nd t he c h a n ne l b an a l o g i n p u t ne t w o r k c o n ne c t i o n . r bi as th e a d 9652 re q u i re s t ha t a 1 0 k r e s is t o r b e p l ac e d b e t w e e n t h e rb i as p i n a n d g r o u n d . t h i s r es i s t o r s ets t h e m a s t er c u r r en t r e f e r en c e o f t h e ad c c o r e a n d m u s t h a ve a t l e a s t a 1 % to l er a n c e. r ef er en ce de c o u p l i n g d e c o u p l e t h e v re f p i n ex t er n a l l y t o g r o u n d wi t h a l o w e s r , 1. 0 f ca p a ci t o r i n p a r a l l e l w i t h a l o w e s r , 0. 1 f ce r a m i c ca p a ci t o r . s pi por t t h e s p i p o r t mu s t n o t b e a c t i ve d u r i n g p er i o d s w h en t h e f u l l d y n a m ic p e r f o r m a n c e o f t he c o n v e r t e r is r e q u ir e d . b e c a u s e t he s c lk , c sb , a n d s d i o si g n a ls a r e t y p i c a l l y a sy n c h r o n o u s t o t he ad c c l o c k , n o i s e f r o m t h e s e si g n a l s c a n d eg r a d e c o n v er t er p e r f o r m anc e . i f t he o n - b o a r d s p i b us i s us e d fo r o t h e r d e v i ces , i t m a y b e n e c e s s a r y t o p r o vi d e b u f f er s b etw e e n t h i s b u s a n d t h e a d 9652 t o ke e p t he s e s i g n a l s f r o m t r an s i t i o n i ng a t t he c o n v e r t e r i n pu t pi n s d u r i n g c r i t i c a l s a m p li n g p e r i o d s. rev. a | page 35 of 36
AD9652 data sheet rev. a | page 36 of 36 outline dimensions * 0. 50 0. 45 0. 40 0. 6 0 r e f 1 . 4 0 1 . 3 4 1 . 1 9 1 . 1 1 1 . 0 1 0 . 9 1 0 . 3 3 n o m 0 . 2 8 m i n a b c d e f g j h k l m 12 11 10 8 7 63 2 1 95 4 10 . 10 10 . 00 s q 9. 90 8. 80 bs c s q 1 1- 1 8- 201 1- a * co m p l i ant w i t h je de c s t and ards m o - 2 75 - e e aa- 1 w i t h t h e exc ep t i o n t o b a l l d i a m et er . co p l anar i t y 0. 12 ball diameter 0.80 bsc detail a a1 bal l co rne r a1 ball corner detail a bottom view t o p vi e w seating plane figure 6 7 . 14 4-b a l l chip s c a l e pa ckag e ba l l gr id a r ray [c sp_ bga ] (bc-14 4-6) dim e nsio ns sho w n i n mi ll im e t er s ordering guide model 1 t e mper a tur e r a nge p a ck age description p a ck age o p tion AD9652bbcz -310 ?40c to +85c 144-ball chi p s c ale p a ck age ball gr id a r r a y [ csp_ b ga ] bc-144-6 AD9652bbczrl 7-310 ?40c to +85c 144-ball chi p s c ale p a ck age ball gr id a r r a y [ csp_ b ga ] bc-144-6 AD9652-310ebz ?40c to +85c eval uation board with AD9652 1 z = r o hs com p li a n t pa rt . ?2014 anal og de vices, inc. all rights reserve d . tra d em ar ks and registered tra d emar ks are the prop erty of their respective o wners. d12169-0-5/14(a)

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