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active receive mixer 400 mhz to 1.2 ghz ad8344 rev. 0 in fo rmation furn ished by an alog d e v i c e s is believed to be accurate and reliable. how e ver, n o resp on sibili ty is assume d b y a n alog de vices fo r its use, nor for an y i n fri n geme nt s of p a t e nt s or ot h e r ri ght s o f th ird parties th at may result fro m its use . s p ecificatio n s subj ec t to ch an g e witho u t n o tice. no licen s e is g r an te d by implicati o n or ot herwi s e u n der a n y p a t e nt or p a t e nt ri ghts of analog de v i ces. trademarks an d registered tra d ema r ks are the prop erty o f their respective ow ners. one technolog y way, p.o . box 9106, norwood, ma 02062-9106, u.s.a. t e l: 781. 329. 4 700 www.analog.com fax: 781. 326. 87 03 ? 2004 analog de vices, i n c. al l r i ght s r e ser v ed . fea t ures broadband rf port: 400 mhz to 1.2 gh z conversion gain: 4.5 db noise figure: 10.5 db input ip3: 24 d b m input p1db : 8.5 db m lo drive: 0 db m external control of mixer bias for low power operation single-ende d , 50 ? rf and lo input ports single-supply operation: 5 v @ 84 ma power-down mode expo sed paddl e lfcsp: 3 mm 3 mm applic a t io ns cellular base st ation receivers ism receivers radio links rf instrument ation func ti on a l bl ock di a g r a m vplo 1 locm 2 loin 3 comm 4 vpd c 12 pw d n 11 exr b 10 comm 9 comm 8 ifop 7 ifom 6 comm 5 comm 13 rfcm 14 rfin 15 vpmx 16 bias 04826-0-001 fi g u r e 1 . gener a l description the ad8344 is a hig h p e r f o r ma n c e , b r o a d b and ac ti v e mixer . i t is w e l l sui t e d for dema ndi n g r e cei v e-ch a n n e l a p plica t io n s t h a t r e q u ir e wi de b a n d wi d t h o n a l l p o r t s a nd v e r y lo w in t e r m o d u l a - t i on d i s t or t i on a n d noi s e f i g u re. the ad8344 p r o v ides a typ i cal co n v ersio n gain o f 4.5 db a t 890 mh z. the in t e g r a t e d l o dr i v er s u p p o r ts a 50 ? in p u t im p e d a n c e wi t h a lo w lo dr i v e le v e l , h e lp in g t o mini mi ze ext e r n al co m p on en t co u n t. t h e s i ng l e - e nd e d 5 0 ? b r o a db a n d r f p o r t a l l o w s for e a s y in t e r f acing t o b o t h ac t i v e de vic e s a nd p a s s i v e f i l t ers. the rf in p u t accep t s in p u t sig n als as larg e as 1.7 v p-p o r 8.5 db m (r e: 50 ?) a t p1db . t h e op e n - c o l l e c t or d i f f e r e n t i a l output s prov i d e e x c e l l e n t b a lan c e a nd c a n b e us e d wi t h a dif f er en t i al f i l t e r o r if a m plif ier , s u c h as t h e ad8 369 o r ad8351. th es e o u t p u t s ma y als o be con - v e r t e d t o a sing le-e n d e d sig n al t h r o ug h th e us e o f a ma t c hin g ne t w or k or a t r ans f or me r ( b a l u n ) . w h e n c e n t e r e d on t h e v p o s s u p p l y v o l t a g e , e a ch o f t h e dif f er en t i al ou t p u t s ma y s w in g 2.5 v p-p . the ad8344 is fa b r ica t e d o n an analog de vices p r o p r i eta r y , hig h p e r f o r ma n c e sig e i c p r o c es s. the a d 834 4 is a v a i la b l e in a 16 -lead lf cs p p a c k a g e . i t o p era t es o v er a ?40c t o +85c t e m p era t ur e ra ng e . an e v al u a t i on b o a r d is als o a v a i lab l e .
ad8344 rev. 0 | page 2 of 20 table of contents specifications ..................................................................................... 3 ac performance ............................................................................... 4 absolute maximum ratings ............................................................ 5 esd caution .................................................................................. 5 pin configuration and function descriptions ............................. 6 typical performance characteristics ............................................. 7 circuit description ......................................................................... 13 ac interfaces ................................................................................... 14 if port .......................................................................................... 14 lo considerations ..................................................................... 15 bias resistor selection ............................................................... 16 conversion gain and if loading ............................................. 16 low if frequency operation .................................................... 17 evaluation board ............................................................................ 18 outline dimensions ....................................................................... 20 ordering guide .......................................................................... 20 revision history 6/04revision 0: initial version
ad8344 rev. 0 | page 3 of 20 specifications v s = 5 v, t a = 25c, f rf = 890 mhz, f lo = 1090 mhz, lo power = 0 dbm, z o = 50 ?, r bias = 2.43 k?, unless otherwise noted. table 1. parameter conditions min typ max unit rf input interface (pin 15, rfin and pin 14, rfcm) return loss 10 db dc bias level internally generated; port must be ac-coupled 2.6 v output interface output impedance differential impedance, f = 200 mhz 9||1 k?||pf dc bias voltage externally generated 4.75 v s 5.25 v power range via a 4:1 balun 13 dbm lo interface lo power ?10 0 +4 dbm return loss 10 db dc bias voltage internally generated; port must be ac-coupled v s ? 1.6 v power-down interface pwdn threshold v s ? 1.4 v pwdn response time device enabled, if outp ut to 90% of its final level 0.4 s device disabled, supply current < 5 ma 0.01 s pwdn input bias current device enabled ?80 a device disabled 100 a power supply positive supply voltage 4.75 v s 5.25 v quiescent current vpdc supply current for bias cells 5 ma vpmx, ifop, ifom supply current for mixer, r bias = 2.43 k? 44 ma vplo supply current for lo limiting amplifier 35 ma total quiescent current 73 84 95 ma power-down current device disabled 500 a
ad8344 rev. 0 | page 4 of 20 ac performance v s = 5 v, t a = 25c, lo power = 0 dbm, z o = 50 ?, r bias = 2.43 k?, unless otherwise noted. table 2. parameter conditions min typ max unit rf frequency range 400 1200 mhz lo frequency range high side lo 470 1600 mhz if frequency range 70 400 mhz conversion gain f rf = 450 mhz, f lo = 550 mhz, f if = 100 mhz 9.25 db f rf = 890 mhz, f lo = 1090 mhz, f if = 200 mhz 4.5 db ssb noise figure f rf = 450 mhz, f lo = 550 mhz, f if = 100 mhz 7.75 db f rf = 890 mhz, f lo = 1090 mhz, f if = 200 mhz 10.5 db input third-order intercept f rf1 = 450 mhz, f rf2 = 451 mhz, f lo = 550 mhz, f if = 100 mhz, each rf tone = ?10 dbm 14 dbm f rf1 = 890 mhz, f rf2 = 891 mhz, f lo = 1090 mhz, f if = 200 mhz, each rf tone = ?10 dbm 24 dbm input second-order intercept f rf1 = 450 mhz, f rf2 = 500 mhz, f lo = 550 mhz, f if = 100 mhz 36 dbm f rf1 = 890 mhz, f rf2 = 940 mhz, f lo = 1090 mhz, f if = 200 mhz 51 dbm input 1 db compression point f rf = 450 mhz, f lo = 550 mhz, f if = 100 mhz 2.5 dbm f rf = 890 mhz, f lo = 1090 mhz, f if = 200 mhz 8.5 dbm lo to if output feedthro ugh lo power = 0 dbm, f rf = 890 mhz, f lo = 1090 mhz ?23 dbc lo to rf input leakage lo power = 0 dbm, f rf = 890 mhz, f lo = 1090 mhz ?48 dbc rf to if output feedthrough rf power = ?10 dbm, f rf = 890 mhz, f lo = 1090 mhz ?32 dbc if/2 spurious rf power = ?10 dbm, f rf = 890 mhz, f lo = 1090 mhz ?66 dbm
ad8344 rev. 0 | page 5 of 2 0 absolute maximum ratings table 3. parameter rating supply voltage, v s 5.5 v rf input level 12 dbm lo input level 12 dbm pwdn pin v s + 0.5 v ifop, ifom bias voltage 5.5 v minimum resistor from exrb to comm 2.4 k? internal power dissipation 580 mw ja 77c/w maximum junction temperature 125c operating temperature range ?40c to +85c storage temperature range ?65c to +150c lead temperature range (soldering 60 sec) 300c s t r e s s es a b o v e t h os e lis t e d u n de r a b s o l u t e m a xi m u m r a t i n g s ma y c a us e p e r m a n en t dama ge t o t h e de vice . this is a s t r e s s ra t - i n g on ly ; f u nc t i on a l op e r a t i o n of t h e d e v i c e a t t h e s e or a n y o t h e r con d i t io ns a b o v e t h o s e i ndic a te d i n t h e op er a t io na l s e c - t i o n o f t h is sp e c if ica t ion is n o t i m plie d . e x p o sur e t o a b s o l u t e max i m u m ra t i ng co ndi t i on s fo r ex ten d e d p e r i o d s ma y a f fe c t de vice r e l i ab i l i t y . esd caution esd (electrostatic discharge) sensitive device. ele c tr ostatic charg e s as high as 4000 v readily accumulate on the human body and test eq uipment and can discharg e wit h out detection. althou gh this product features proprietary esd protection circu i try, permanent dama ge may occur on devices subjected to high energy electrostatic discharges. theref ore, prop er esd precautions a r e recommended to avoid perform a nce degradation or l o ss of functiona l ity.
ad8344 rev. 0 | page 6 of 2 0 pin conf iguration and fu nction descriptions vplo 1 locm 2 loin 3 comm 4 vpd c 12 pw d n 11 exr b 10 comm 9 comm 8 ifop 7 ifom 6 comm 5 comm 13 rfcm 14 rfin 15 vpmx 16 04826-0-002 f i g u re 2. 16-l e ad l f csp ta ble 4. pi n f u nct i on d e s c ri pt i o ns pin o. neonic function 1 vplo positive supply voltage for the lo buffer: 4.75 v to 5.25 v. 2 locm ac ground for limiting lo amplifier, ac-couple d to ground. 3 loin lo input. nominal input leve l 0 dbm, input level range ?10 db m to +4 dbm, re: 50 ?, ac-coupled. 4, 5, 8, 9, 13 comm device common (dc ground). 6, 7 ifom, ifop differential if outputs; open collect ors, each requires dc bi as of 5.00 v (nominal). 1 0 e x r b mixer bias voltage, connect resistor from exrb to ground, t y pical value of 2.43 k? sets mixer current to nominal value. minimum re sistor value from exrb to grou nd = 2.4 k?. 11 pwdn connect to ground for no rmal operation. con n ect pin to v s for dis a bl e mode. 12 vpdc positive supply voltage for the dc bias cell: 4.75 v to 5.25 v. 14 rfcm ac ground for r f input, ac-cou pled to ground. 15 rfin rf input. must be ac-coupl ed. 16 vpmx positive supply voltage for the mixer: 4.75 v to 5.25 v.
ad8344 rev. 0 | page 7 of 2 0 typical perf orm ance cha r acte ristics 12 ?2 0 2 4 6 8 10 400 500 600 700 800 900 1000 1100 1200 04826-0-010 rf frequency (mhz) gain ( d b) if = 100mhz if = 200mhz if = 400mhz if = 70mhz f i gure 3. con v ers i o n g a in v s . rf f r equ e nc y 6.0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 ? 1 0 ? 9 ? 8 ? 7 ? 6 ? 5 ? 4 ? 3 ? 2 ? 1 01234 04826-0-022 lo level (dbm) gain ( d b) f i g u r e 4. c o nve r s i o n g a in v s . l o p o we r , f rf = 89 0 m h z, f if = 20 0 m h z 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 ?4 0 8 0 70 60 50 40 30 20 10 0 ?10 ?2 0 ?30 04826-0-018 temperature ( c) gain ( d b) v s = 4.75v v s = 5.0v v s = 5.25v f i gur e 5 . co n v e r s i on gai n vs . t e m p er atur e , f rf = 89 0 m h z , f lo = 10 90 m h z 10 0 1 2 3 4 5 6 7 8 9 80 120 160 200 240 280 320 360 400 04826-0-011 if frequency (mhz) gain ( d b) rf = 450mhz rf = 890mhz f i gure 6. con v ers i o n g a in v s . if f r equ e nc y 45 0 5 10 15 20 25 35 40 30 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4 04826-0-031 gain (db) p e rce ntage gain percentage normal (mean = 4.47, std dev = 0.18) f i gure 7. con v ers i o n g a in d i s t ributi on , f rf = 89 0 mh z , f if = 200 mh z
ad8344 rev. 0 | page 8 of 2 0 28 26 24 22 20 18 16 14 12 10 400 500 600 700 800 900 1000 1100 1200 04826-0-012 rf frequency (mhz) input ip3 ( d bm) if = 100mhz if = 200mhz if = 400mhz if = 70mhz f i gure 8. input i p 3 v s . rf f r equenc y (r f t o n e sp ac ing = 1 mh z) 25.0 20.0 20.5 21.0 21.5 22.0 22.5 23.0 23.5 24.0 24.5 ? 1 0 ? 9 ? 8 ? 7 ? 6 ? 5 ? 4 ? 3 ? 2 ? 1 01234 04826-0-023 lo level (dbm) input ip3 ( d bm) f i g u re 9. input i p 3 v s . l o p o we r , f rf 1 = 89 0 m h z, f rf 2 = 89 1 m h z, f lo = 10 90 m h z 30 29 28 27 26 25 24 23 22 21 20 ?4 0 8 0 70 60 50 40 30 20 10 0 ?10 ?2 0 ?30 04826-0-019 temperature ( c) input ip3 ( d bm) v s = 4.75v v s = 5.0v v s = 5.25v f i g u re 10. input i p 3 v s . t e mper at ure , f rf 1 = 89 0 m h z, f rf 2 = 89 1 m h z, f lo = 10 90 m h z 30 10 12 14 16 18 20 22 24 26 28 80 120 160 200 240 280 320 360 400 04826-0-013 if frequency (mhz) input ip3 ( d bm) rf = 890mhz rf = 450mhz f i gure 11. input i p 3 vs. if f r equ e nc y (r f t o n e sp ac ing = 1 mhz) 35 0 5 10 15 20 25 30 23.0 23.2 23.4 23.6 23.8 24.0 24.2 24.4 24.6 25.0 24.8 04826-0-032 input ip3 (dbm) p e rce ntage ip3 percentage normal (mean = 24.023, std dev = 0.24) f i gure 12. input i p 3 d i s t ribut i on , f rf 1 = 89 0 m h z, f rf 2 = 89 1 m h z, f lo = 10 90 m h z
ad8344 rev. 0 | page 9 of 2 0 50 48 46 44 42 40 38 36 34 32 30 400 500 600 700 800 900 1000 1100 1200 04826-0-033 rf frequency (mhz) input ip2 ( d bm) if = 200 if = 100 if = 400 if = 70 f i gure 13. input i p 2 v s . rf f r eque nc y (rf t o n e sp ac ing = 5 0 mh z) 60 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 ? 1 0 ? 9? 8? 7 ? 6? 5? 4? 3? 2? 1 0 1 2 3 4 04826-0-034 lo level (dbm) input ip2 ( d bm) f i g u re 14. input i p 2 v s . l o p o we r , f rf = 89 0 m h z, f lo = 1 0 90 m h z (rf t o ne sp aci n g = 5 0 m h z) 40 42 44 46 48 50 52 54 ? 4 0 ? 3 0 ? 2 0 ? 1 0 0 1 02 03 0 4 05 06 0 7 08 0 04826-0-037 temperature ( c) input ip2 ( d bm) 4.75v 5.0v 5.25v f i g u re 15. input i p 2 v s . t e mper at ure , f rf = 8 9 0 mh z, f lo = 1 0 90 m h z (rf t o n e sp ac ing = 5 0 mh z) 50 52 54 56 58 60 30 32 34 36 38 40 42 44 46 48 80 120 160 200 240 280 320 360 400 04826-0-015 if frequency (mhz) input ip2 ( d bm) rf = 450mhz rf = 890mhz f i gure 16. input i p 2 v s . if f r equ e nc y (r f t o n e sp ac ing = 5 0 mh z) 35 0 5 10 15 20 25 30 44 45 46 47 48 49 50 51 52 55 54 53 04826-0-035 input ip2 (dbm) p e rce ntage iip2 percentage normal (mean = 48.96, std dev = 01.17) f i gure 17. input i p 2 d i s t ribut i on , f rf = 89 0 m h z, f lo = 1 0 90 m h z (rf t o n e sp ac ing = 5 0 mh z)
ad8344 rev. 0 | page 10 of 20 12 0 2 4 6 8 10 400 500 600 700 800 900 1000 1100 1200 04826-0-016 rf frequency (mhz) in pu t p1db ( d b m ) if = 100mhz if = 200mhz if = 400mhz if = 70mhz f i gure 18. input p1db vs . rf f r equ e nc y 9.0 7.0 7.2 7.4 7.6 7.8 8.0 8.2 8.4 8.6 8.8 ? 1 0 ? 9 ? 8 ? 7 ? 6 ? 5 ? 4 ? 3 ? 2 ? 1 01234 04826-0-024 lo level (dbm) in pu t p1db ( d b m ) f i gure 19. input p1db vs . l o p o w e r , f rf = 89 0 m h z, f lo = 10 90 m h z 10.0 9.5 9.0 8.5 8.0 7.5 7.0 6.5 6.0 5.5 5.0 ?4 0 8 0 70 60 50 40 30 20 10 0 ?10 ?2 0 ?30 04826-0-020 temperature ( c) in pu t p1db ( d b m ) v s = 4.75v v s = 5.0v v s = 5.25v f i gure 20. input p1db vs . t e mper ature , f rf = 89 0 mh z , f lo = 1 0 90 m h z 10 9 8 7 6 5 4 3 2 1 0 80 120 160 200 240 280 320 360 400 04826-0-017 if frequency (mhz) in pu t p1db ( d b m ) rf = 450mhz rf = 890mhz f i gure 21. input p1db vs . if f r eq uenc y 60 55 50 45 40 35 30 25 20 15 10 5 0 7.0 7.5 8.0 8.5 9.0 9.5 10.0 04826-0-036 input p1db (dbm) p e rce ntage input p1db percentage normal (mean = 8.50, std dev = 0.38) f i gure 22. input p1db d i strib u tion, f rf = 8 9 0 mh z, f lo = 10 90 m h z
ad8344 rev. 0 | page 11 of 20 25 20 15 10 5 0 100 95 90 85 80 75 70 65 60 55 50 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 04826-0-026 r bias (k ? ) nf and ip 3 (dbm) s u p p l y curre nt (ma) noise figure input ip3 current f i gure 23. no is e f i g u re , input i p 3 a n d s u p p ly cu rrent v s . r bias , f rf 1 = 89 0 mhz, f rf 2 = 89 1 m h z, f lo = 1 0 90 m h z 14 13 12 11 10 9 8 7 6 400 500 600 700 800 900 1000 1100 1200 04826-0-027 rf frequency (mhz) nois e figure s s b (dbm) if = 70 if = 100 if = 200 if = 400 fi g u r e 2 4 . n o i s e fi g u r e v s . r f f r e q u e n c y 13.5 13.0 12.5 12.0 11.5 11.0 10.5 10.0 ? 1 5 ? 1 3 ? 1 1 ? 9? 7? 5? 3? 1 1 3 5 04826-0-029 lo power (dbm) nois e figure s s b (dbm) fi g u r e 2 5 . n o i s e fi g u r e v s . l o po w e r , f rf = 8 9 0 mh z, f lo = 10 90 m h z 14 ?2 0 2 4 6 8 10 12 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 04826-0-025 r bias (k ? ) in pu t p1db ( d b m ) f i gure 26. input p1db vs . r bias, f rf = 8 9 0 mh z, f lo = 1 0 90 m h z 11.0 10.5 10.0 9.5 9.0 8.5 8.0 7.5 7.0 6.5 6.0 70 100 150 200 250 300 350 400 04826-0-028 if frequency (mhz) nois e figure s s b (dbm) 890mhz 450mhz fi g u r e 2 7 . n o i s e fi g u r e v s . i f f r e q u e n c y 100 95 90 85 80 75 70 65 60 ?4 0 8 0 70 60 50 40 30 20 10 0 ?10 ?2 0 ?30 04826-0-021 temperature ( c) curre nt (ma) v s = 4.75v v s = 5.0v v s = 5.25v f i gure 28. t o t a l su p p ly cu rr e n t v s . t e mpe r atu r e
ad8344 rev. 0 | page 12 of 20 04826-0-051 0 180 30 330 60 90 270 300 120 240 150 210 1.2ghz 400mhz f i gur e 2 9 . rfin re t u r n l o ss vs . rf f r e q ue nc y 0 ?45 ?40 ?35 ?30 ?25 ?20 ?15 ?10 ?5 400 500 600 700 800 900 1000 1100 1200 04826-0-053 rf frequency (mhz) fe e d through (dbc ) f i gure 30. rf to if f eedthrou g h v s . rf f r equ e nc y , f lo = 109 0 mhz , rf p o w e r = ?1 0 dbm 0 ?80 ?70 ?60 ?50 ?40 ?30 ?20 ?10 400 600 800 1000 1200 1400 1600 04826-0-055 lo frequency (mhz) le akage (dbc ) f i g u r e 3 1 . lo t o r f l e a k a g e v s . lo f r e q u e n c y , lo p o w e r = 0 d b m 04826-0-052 0 180 30 330 60 90 270 300 120 240 150 210 400mhz 1.6ghz f i gure 32. l o in r e t u rn l o s s v s . l o f r eq uenc y 0 ?40 ?35 ?30 ?25 ?20 ?15 ?10 ?5 400 600 800 1000 1200 1400 1600 04826-0-054 lo frequency (mhz) fe e d through (dbc ) f i g u r e 3 3 . lo t o i f f e e d t h r o u g h v s . lo f r e q u e n c y , lo p o w e r = 0 d b m 14000 12000 10000 8000 6000 4000 2000 3.0 2.5 2.0 1.5 1.0 0.5 0 70 370 320 270 220 170 120 04826-0-030 frequency (mhz) re s i s t ance ( ? ) cap acitance (pf) f i gure 34. if p o r t o u tput r e sistanc e a n d cap a cit a nce v s . if f r equenc y
ad8344 rev. 0 | page 13 of 20 e circuit description the ad8344 is a do wn con v er tin g mixer o p timize d f o r o p era - tio n wi thin t h e in p u t f r eq uen c y ra n g e o f 400 mh z t o 1.2 g h z. i t has a sin g le -e n d e d , 50 ? rf in pu t, as w e l l as a si n g le-e n d e d , 50 ? lo cal os ci l l a t o r (l o) i n p u t. the if o u t p u t s a r e dif f er en t i al o p en col l e c t o rs. the mixer c u r r en t c a n b e ad j u st e d b y t h e val u e of an e x te r n a l re s i stor to opt i m i z e p e r f or m a nc e f o r g a i n c o m - p r essio n an d in ter m o d u l a t ion or fo r lo w p o w e r o p era t ion. f i gur e 35 s h o w s t h e b a sic b l o c ks o f t h e mixer , w h ich i n cl udes t h e lo b u f f er , rf v o l t a g e-t o -c ur r e n t con v er t e r , b i as ce l l , and mix i n g co r e . the rf v o l t a g e t o rf c u r r en t co n v ersio n is don e v i a an ind u c t i v e l y degen e r a t e d dif f er e n t i al p a ir . w h en o n e side o f t h e dif f er en t i a l p a ir is ac g r o u n d e d , t h e o t h e r i n p u t ca n b e dr i v en sin g le-e n d e d . th e rf i n p u ts can als o b e dr i v en dif f er en t i al l y . the v o l t a g e-t o - c ur r e n t co n v er ter t h en dr i v es t h e e m i t t e rs o f a fo ur -t ra n s ist o r s w i t chi n g co r e . t h is sw i t chin g cor e is dr i v en b y a n am plif ie d ve rsio n o f t h e lo ca l os ci l l a t o r sig n a l co n n e c t e d t o t h e lo in p u t. th er e a r e t h r e e l i mi t i n g ga in s t a g es b e tw e e n t h e ext e r n al l o sig n al a nd t h e s w i t chin g co r e . th e f i rs t s t a g e con - v e r t s t h e sin g le - e n d e d lo dr i v e t o a w e l l b a lan c e d dif f er en t i al dr i v e . th e dif f er en t i al dr i v e t h e n p a s s es t h r o ug h tw o m o r e ga i n s t a g es, w h ich e n s u r e s a limi t e d sig n al dr i v es t h e sw i t chin g co r e . t h i s a f f o r d s th e use r a l o w e r l o d r i v e r e q u i r em en t , w h il e ma in t a in in g excel l en t di sto r t i o n a nd co m p r e ssi o n p e r f o r ma n c e. the o u t p u t sig n al o f t h es e t h r e e l o ga in s t a g es dr i v es t h e fo ur tra n si s t o r s wi th in th e m i x e r co r e t o co m m u t a t e a t t h e ra t e o f th lo cal os cil l a t o r f r eq uen c y . th e ou t p u t o f th e mixer co r e is tak e n dir e c t l y f r o m t h es e o p e n col l e c t o rs. th e o p en c o l l e c t o r o u t p u t s p r es en t a hig h i m p e dance a t t h e if f r e q uen c y . the con v ersio n ga in o f t h e mixe r dep e n d s dir e c t l y o n t h e i m p e dan c e p r es en t e d t o th es e op en c o l l ec t o rs. i n c h a r ac t e r i za tion, a 200 ? lo ad was p r es en te d to t h e p a r t vi a a 4:1 i m p e dance t r a n s f o r m e r . the ad8344 als o f e a t ur es a p o wer - do wn f u n c tio n . a p p l i c a t i o n o f a logi c l o w a t th e pw d n p i n allo w s n o rm al o p er a t ion. a h i g h lo g i c le vel a t t h e p w dn p i n sh u t s down t h e ad8344. p o w e r co n s um p t io n w h en the p a r t is dis a b l e d is les s tha n 10 mw . the b i as f o r th e mixer is s e t wi t h a n ext e r n al r e sis t o r f r o m th e e x r b pi n to g r ou n d . t h e v a lu e of t h i s re s i stor d i re c t ly af f e c t s t h e d y na mic ra n g e o f t h e mixer . th e ext e r n al r e sis t o r s h o u ld no t be lo w e r tha n 2. 4 k?. p e r m a n en t dama g e t o th e p a r t wil l r e s u l t if val u es be lo w 2.4 k? a r e us ed . 04826-0-003 lo input vplo ifop ifom rfin vpmx rfcm bias external bias resistor vpdc pwdn se to diff f i g u re 35. a d 8 3 4 4 simp lif ied s c h e ma t i c a s sh o w n in f i g u r e 36, th e if o u t p u t p i n s , ifop a nd ifo m , a r e d i r e ctl y c o n n e ct ed t o th e o p en co ll ect o r s o f th e n p n tra n s i s t o r s in t h e mixer co r e s o t h e dif f er en t i al and sin g le -e n d e d i m p e d- anc e s l o o k i n g i n to t h i s p o r t are rel a t i vely h i g h , on t h e ord e r of s e ver a l k? . a conn e c t i o n b e tw e e n t h e su p p ly vol t a g e and t h es e output pi ns i s re qu i r e d f o r prop e r m i x e r c o re op e r a t i o n . 04826-0-003 ifop ifom loin rfcm rfin comm f i g u r e 3 6 . mi x e r c o r e sim p li fi e d sch e m a ti c the ad8344 has thr e e p i n s f o r th e su p p l y v o l t ag e: vp d c , vpmx, an d vplo . th es e p i ns a r e s e p a r a te d to minim i ze o r e l imina t e p o s s ib le p a rasi tic co u p lin g p a th s wi thin t h e ad8344 tha t co u l d ca us e s p ur io us sig n al s o r r e d u ced in ter p o r t is ola t io n. c o ns e q u e n t ly , e a ch of t h e s e p i ns shou l d b e wel l b y p a ss e d and deco u p led as c l os e t o th e ad83 44 as p o s s ib le .
ad8344 rev. 0 | page 14 of 20 ac interfaces the ad8344 is a hig h -side do wn con v er t e r . i t is desig n e d t o do w n con v er t r a dio f r e q uen c ies (rf ) to lo w e r in ter m e d i a te f r eq uen c ies (if) usin g a hig h -side lo cal os cil l a to r (l o). th e lo is in j e c t e d in t o t h e m i xer co r e a t a f r e q uen c y g r e a t e r t h an t h e desir e d i n p u t r f f r e q uen c y . the dif f er en ce b e t w e e n t h e lo and rf f r e q uen c ies, f lo ? f rf , is th e i f f r eq uen c y , f if . i n a d d i t i o n t o t h e desir e d rf s i g n a l , a n rf im a g e wi l l b e do w n con v er te d to t h e s a me if f r eq uenc y . th e ima g e f r eq uen c y is a t f lo + f if . t h e c o n - v e rsio n ga in o f t h e ad8344 decr eas e s wi t h in cr easin g in p u t f r e q uen c y . by ch o o sin g t o us e a hig h -si d e l o t h e i m a g e f r e - qu e n c y at f lo + f if is tra n s l a t e d wi th les s con v ersio n ga in tha n t h e desir e d rf s i g n a l a t f lo ? f if . a d d i t i o n a l ly , an y wideb a nd n o is e p r es en t a t t h e i m a g e f r e q u e n c y w i l l b e do w n con v er t e d wi t h les s con v ersio n ga in tha n w o u l d be t h e cas e if a lo w-side l o was a p p l ie d . i n g e n e ral , a hig h -side l o sh ou ld be us e d wi t h th e ad8344 t o en s u r e o p tima l n o is e p e r f o r ma n c e an d ima g e re j e c t i o n . the ad8344 is desig n e d t o o p era t e usin g rf f r eq uen c ies in t h e 400 mh z t o 120 0 mh z f r eq uenc y ra n g e , wi t h hig h -side l o in jec t io n wi thin th e 470 m h z to 1600 mh z ran g e . i t is es s e n t ial t o ac-co u ple rf a nd l o p o r t s to p r e v en t dc o f fs ets f r o m sk e w - in g t h e mixer c o r e in an asy m m e t r ica l m a n n e r , p o t e n t ia l l y deg r adi n g li n e ar in p u t s w in g and im p a c t in g di sto r t i o n and in p u t c o m p re ss i o n char ac te r i st i c s . the ad8344 rfin p o r t p r es en ts a 50 ? im p e da n c e r e l a ti v e t o rfcm. i n o r der t o en s u r e a g o o d im p e dan c e ma t c h, t h e rfin a c - c oupl i n g c a p a c i tor s h ou l d b e l a r g e e n ou g h i n v a lu e s o t h a t t h e p r es e n t e d r e ac t a n c e is n e g l i g i b le a t t h e i n t e n d e d rf f r e - q u e n c y . a d d i t i o n a l l y , t h e r f c m b y p a s s i n g c a p a c i t o r s h o u l d b e s u f f i cien t l y la rge t o p r o v ide a lo w im p e dan c e r e t u r n p a t h t o b o a r d g r o u nd . l o w ind u c t an ce cer a mic g r ade c a p a ci to rs o f n o m o r e than 330 pf a r e s u f f i cien t f o r m o s t a p p l ic a t io n s . s i mil a rl y th e lo in p o r t p r o v ides a 50 ? lo ad im p e dan c e wi t h co mm o n -mo d e deco u p lin g on l o cm. a g a i n, c o mm on g r ade cera mic c a p a ci to rs wil l p r o v ide s u f f i cien t sig n al co u p lin g and b y p a ssin g o f t h e lo in t e r f ace . 04826-0-040 0 180 30 330 10mhz 500mhz 60 90 270 300 120 240 150 210 f i gure 37. if p o r t r e flec t i on co effic i en t fr o m 1 0 m h z to 5 00 m h z if port the if p o r t us es a n o p e n col l e c t o r dif f er en t i al o u t p ut in t e r f ace. the n p n op en col l e c to rs ca n b e m o dele d as h i g h im p e dan c e cu rr e n t so u r c e s . t h e s t ra y ca pa ci ta n c e a s socia t ed wi th th e i c pa c k a g e p r e s en ts a s l i g h t l y c a pac i ti v e so u r c e i m ped a n c e as i n f i gur e 37. i n g e n e ral , t h e ifo p a nd ifo m o u t p u t p o r t s can be m o de le d as c u r r en t s o ur ces wi t h a n im p e dan c e o f ~10 k? in pa ralle l w i t h ~1 pf o f s h un t ca p a ci ta n c e . c i r c ui t boa r d tra c e s co nne c t in g t h e if o u t p u t s to t h e lo ad sh o u l d b e na r r o w a n d s h o r t t o p r e v en t exces s i v e ca p a c i t i v e lo adin g. i n o r der t o ma in - t a in t h e sp e c if ie d con v ersio n gain o f t h e mixer , t h e if o u t p u t p o r t s s h o u ld b e lo aded in t o 200 ?. i t is n o t n e ces s a r y t o a t t e m p t t o p r o v ide a con j uga t e ma t c h t o th e if p o r t o u t p u t s o ur ce im p e dan c e . i f t h e if sig n al n e e d s t o be de li v e r e d t o a r e m o t e lo ad , m o r e t h an a fe w ce n t i m e t e r s a w a y , i t ma y b e n e ce ss a r y t o us e a n a p p r o p r i a t e b u f f er a m p l if ier t o p r es en t a r e al 200 ? lo ad- in g i m p e dan c e a t t h e if o u t p u t in t e r f ace . the b u f f er a m plif ier shou l d h a ve t h e a ppropr i a t e s o u r c e i m p e d a nc e t o m a tch t h e cha r ac ter i st ic i m p e dance o f t h e s e le c t e d t r a n s m issio n li ne. an exa m p l e is p r o v ided in f i gur e 3 8 , wh er e t h e ad8351 dif f er en tia l a m plif ier is us e d t o dr i v e a p a ir o f 75 ? t r a n smissio n li n e s. t h e ga in o f the b u f f er ca n be indep e n d en tl y s e t b y c h o o sin g an a ppropr i a t e g a i n re s i stor , r g . 04826-0-041 comm 8 ifop 7 ifom 6 comm 5 ad8344 ad8351 + ? r f c + v s r f c z l = 2 0 0 ? + v s + v s 200 ? r g z l tx line z o = 75 ? tx line z o = 75 ? f i g u re 38. a d 8 3 5 1 u s ed as t r ans m is s i on l i ne d r ive r and i m ped a nce buf f e r
ad8344 rev. 0 | page 15 of 20 the hig h in p u t im p e dance o f the ad8351 al lo ws f o r a s h un t dif f er en tial t e r m ina t io n t o p r o v ide t h e desir e d 200 ? lo ad t o th e ad8344 if o u t p u t p o r t . i t i s ne c e ss ar y to bi a s t h e op e n c o l l e c tor output s u s i n g one of t h e s c h e m e s p r es en te d i n f i gur e 39 a nd f i gur e 4 0 . f i gur e 39 i l l u st r a tes t h e a p plica t io n o f a c e n t er -t a p p e d i m p e dan c e t r a n s - fo r m er . th e t u r n s ra t i o o f t h e t r a n sfo r m e r s h o u ld b e s e le c t e d t o prov i d e t h e d e s i re d i m p e d a nc e t r ans f or m a t i on . i n t h e c a s e of a 50 ? lo ad im p e dan c e, a 4-to -1 i m p e dance r a t i o t r a n sfo r m e r s h o u ld b e us ed t o tra n sf o r m the 50 ? lo ad in t o a 200 ? dif f er en tial lo ad a t t h e if o u t p u t p i n s . f i gur e 40 il l u s t ra t e s a dif f er en t i al if i n t e r f ace w h er e p u l l -u p ch ok e i n d u c t o r s a r e us e d to bi a s t h e op e n - c o l l e c t or output s . t h e s h u n t i ng i m p e d a nc e of t h e ch ok e i n d u c t o r s us e d t o co uple dc c u r r en t in t o t h e mixer c o re shou l d b e l a r g e e n ou g h a t t h e i f f r e q u e nc y of op e r a t i o n a s t o n o t lo ad do w n t h e o u t p u t c u r r en t b e fo r e r e achin g t h e in te nde d lo ad . a d d i t i o n a l ly , t h e dc c u r r en t han d l i n g c a p a b i li t y o f th e s e lec t ed ch ok e ind u c t o r s n e e d s t o b e a t leas t 45 ma. th e s e lf r e s o na n t f r e q uen c y o f th e s e le c t e d ch ok e sho u ld be hig h er t h a n t h e i n t e n d e d if f r e q uen c y . a va r i ety o f s u i t a b le ch ok e ind u c t o r s a r e commer c ia l l y a v ai la b l e f r o m man u fac t ur ers such a s m u r a t a a n d c o i l c r af t . a n i m p e d a nc e t r ans f o r m i ng ne t w or k ma y b e r e q u ir e d t o tra n sf o r m th e f i nal lo ad im p e dan c e t o 200 ? a t t h e if o u t p u t s. th er e a r e s e veral go o d r e fer e n c e b o oks t h a t e x pl ai n ge ne r a l i m p e d a nc e m a t c h i ng pro c e d u r e s , i n clu d i n g : ? ch ri s b o w i c k , rf c i r c u i t des i gn , n e w n e s , r e p r i n t e d i t i o n , 1997. ? da v i d m. p o z a r , m i cr o w a v e e n g i n e er i n g , w i ley t e xt b o oks, s e con d e d i t ion, 1997. ? gu i l l e r m o g o n z a l e z , m i c r o w av e t r an s i s t o r a m p l i f i e r s : a n a l y - si s an d d e s i g n , p r en tice h a l l , s e co nd e d i t ion, 1996. 04826-0-042 comm 8 ifop 7 ifom 6 comm 5 ad8344 z l = 2 0 0 ? i f o u t z o = 5 0 ? + v s 4:1 f i gure 39. bi asing t h e if p o r t o p en co l l ec tor o u tputs u s ing a cente r - t ap ped i m ped a nc e t r a n s f orm e r 04826-0-043 comm 8 ifop 7 ifom 6 comm 5 ad8344 r f c + v s r f c z l = 2 0 0 ? i f o u t + i f o u t ? + v s z l impedance transforming network f i gure 40. bi asing t h e if p o r t o p en co l l ec tor o u tputs u s ing p u ll-u p c h oke induc t ors 04826-0-044 0 180 30 330 50mhz 50mhz 500mhz 500mhz 60 90 270 300 120 240 150 210 real chokes ideal chokes f i g u re 41. if p o r t l oad ing e f f e c t s due to f i n i te - q p u ll-u p induc t o r s (m ur at a blm 1 8h d 6 0 1 sn 1d ch ok es ) lo consi d e r atio ns the l o sig n al ne e d s t o ha ve ade q u a t e phas e n o is e cha r ac t e r i s - t i cs an d r e as onab le lo w s e co nd ha r m o n ic con t e n t t o p r e v en t deg r ada t ion o f th e n o is e f i gur e p e r f o r ma n c e o f th e ad8344. a lo pla g ue d wi t h p o o r phas e no is e can r e su l t i n r e ci p r o c a l mix i ng, a m e ch a n ism t h a t c a us es sp e c t r a l sp r e adin g o f t h e do w n con v er te d sig n a l , limi t i n g t h e s e n s i t i v i t y o f t h e m i xer a t f r e q uen c ies c l os e-in t o an y la rg e in p u t sig n als. th e in t e r n al lo b u f f er p r o v ides en o u g h ga in t o ha r d limi t t h e i n p u t lo an d prov i d e f a s t s w itch i n g of t h e m i x e r c o re. o d d h a r m on i c c o n t e n t p r es en t on t h e lo dr i v e sig n al sh o u ld n o t im p a c t mixer p e r f o r ma n c e; ho w e v e r , e v en-o r d er ha r m o n ics c a us e t h e mixer co r e t o co mm u t a t e in an u n bal a n c e d mann er , p o t e n t ial l y d e g r a d i n g noi s e p e r f or m a nc e. si m p l e lu m p e d el e m e n t l o w - p a s s f i l t er in g can b e a p plie d t o h e l p r e j e c t t h e ha r m o n ic co n t en t o f a g i v e n lo cal os cil l a t o r , as il l u s t r a ted in f i gur e 42. the f i l t er dep i c t e d is a comm on 3-p o le c h eb ysh e v , desig n e d t o ma in t a in a 1-t o -1 s o ur ce-to-lo ad im p e dance ra tio wi t h n o m o r e than 0.5 db o f r i p p le in t h e p a s s b a n d . o t h e r f i l t er s t r u c t ur es ca n b e ef fe c t i v e as lo n g as t h e s e cond ha r m o n ic o f t h e l o is f i l t er e d t o n e g l ig ib le le ve ls, e . g., ~30 db be l o w th e f u ndamen t al . the m e as- ur ed f r eq uen c y r e s p o n s e o f t h e ch eb ysh e v f i l t er f o r a 1200 mh z ?3 db c u t o f f f r eq uen c y is p r es en t e d in f i gur e 4 3 . 04826-0-045 ad8344 loin 3 comm 4 locm 2 r l for r s = r l f c - filter cutoff frequency r s c1 c3 lo source l2 c1 = 1.864 2 f c r l c3 = 1.834 2 f c r l l2 = 1.28r l 2 f c f i g u re 42. u s ing a l o w- p a s s f ilt er to r e duc e l o s econd h a rm oni c
ad8344 rev. 0 | page 16 of 20 0 ?50 ?45 ?40 ?35 ?30 ?25 ?20 ?15 ?10 ?5 0.1 1 1 0 04826-0-046 frequency (ghz) r espon se ( d b ) ideal lpf real lpf 4.7pf 4.7pf 6.8nh fi g u r e 4 3 . m e a s u r e d a n d i d e a l l o fi l t e r fr e q u e n c y r e s p o n s e bias resistor selection an ext e r n al b i as r e sis t o r is us ed t o s e t t h e dc c u r r en t in t h e mixer co r e . this p r o v ides t h e a b i l i t y t o r e d u ce p o w e r co n s um p - tio n a t the exp e n s e o f decr eas e d d y na mic ra n g e . f i gur e 44 s h o w s t h e sp ur io us-f r e e d y na mic ra n g e (s fd r) o f t h e mixer fo r a 1 hz noi s e b a nd w i d t h ve r s u s t h e r bi a s re s i stor v a lu e. sf dr was calc u l a t e d usin g nf an d ii p3 da ta col l ec te d a t 900 m h z. by def i ni t i o n , () ) ( 10log 3 2 b kt nf iip3 sfdr ? ? ? = w h er e iip3 is t h e in p u t t h ir d - o r der in t e r c e p t i n dbm. nf is t h e noi s e f i g u re i n d b . kt is t h e t h e r ma l n o is e p o wer den s i t y and i s ?173.86 db m/h z a t 298 k. b is t h e n o is e b a n d w i d t h i n h z . i n o r der to ca lc u l a t e t h e a n t i ci p a te d s f dr fo r a g i ven a p plic a - ti o n , i t i s n e ce s s a r y t o fa ct o r i n th e a c t u a l n o ise ba n d w id th . f o r i n s t a n ce , i f th e if n o i s e b a n d w id th wa s 5 mh z , th e a n ti ci pa t e d s f d r usin g a 2. 43 k? r bi a s w o u l d be 6.66 log10 (5 mh z) les s tha n t h e 1 h z da ta in f i gur e 44 o r ~80 db c. u s in g a 2.43 k? b i as r e sis t o r wil l s e t th e q u ies c en t p o w e r dis s i p a t ion t o ~415 mw f o r a 5 v su p p ly . i f t h e r bi a s r e sis t o r val u e was ra is e d t o 3.9 k?, th e s f dr fo r t h e s a m e 5 m h z b a nd w i d t h w o u l d b e r e d u ce d to ~77.5 db c an d t h e p o w e r dissi p a t io n w o u l d b e r e d u ce d to ~ 3 3 5 m w . i n l o w po w e r po r t a b l e a p p l i c a t i o n s i t m a y be a d v a n t a - g e o u s t o r e d u ce p o w e r c o n s um p t io n b y usin g a la r g er val u e o f r bi a s , a ssu m i ng re d u c e d dy n a m i c r a nge p e r f o r m a nc e i s a c c e pt ab l e . 125 120 85 81 77 73 69 65 121 122 123 124 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 04826-0-047 r bias (k ? ) s f dr (dbc ) s u p p l y curre nt (ma) ad8344 comm 9 exrb 10 pwdn 11 vpdc 12 +v s r bias f i g u re 44. imp a c t o f r bias resi sto r sel e c t i o n vs . spurio us -f r ee d y namic range an d p o wer consu m ption, f rf = 89 0 m h z and f lo = 1 0 90 m h z co nv ersi on gain and i f lo ad in g the ad8344 is o p timize d f o r dr i v in g a 200 ? dif f er en tial lo ad . a l t h o u g h t h e de v i ce is c a p a b l e o f dr i v in g a w i de va r i ety o f l o a d s , i n ord e r to m a i n t a i n opt i m u m d i stor t i on an d noi s e p e r f o r ma n c e , i t is ad vi s e d t h a t t h e p r es e n te d lo ad a t t h e if o u t p u t s is r e as ona b l y c l os e t o 200 ?. f i gur e 45 il l u s t ra t e s t h e e f f e c t of i f lo a d i n g on c o n v e r s i on g a i n . t h e m i x e r output s b e ha v e li k e n o r t o n e q u i valen t s o ur ces, w h er e t h e con v ersion ga in is t h e ef fe c t i v e t r a n s c ond u c t a n c e o f t h e mi xer m u l t i p lie d b y t h e lo adin g i m p e dance . th e lin e a r dif f er en t i al v o l t a g e c o n v e r s i on g a i n of t h e m i x e r c a n b e mo d e l e d a s rf m m load f g j g r av + ? = 37.70 1 0.46 w h er e r loa d is t h e dif f er en t i al lo adin g i m p e dan c e . g m is t h e mixer tra n s c ond u c t an ce and is eq ual t o 4070/r bi a s . f rf is t h e f r eq ue n c y o f th e si gn al a p p l ied t o th e r f po r t in gh z . l a rg e im p e dan c e lo ads ca us e t h e co n v ersion ga i n t o i n cr e a s e , r e su l t in g i n a de cr e a s e in in pu t l i n e a r i t y an d a l lo wa b l e sig n a l swin g. i n o r der t o ma in ta in p o si ti v e con v ersion ga in and p r e- s e r v e s p ur io us-f r e e d y na mic ra n g e p e r f o r ma n c e , t h e dif f er en t i a l lo ad p r es en t e d a t t h e if p o r t sho u ld r e ma in w i t h in a ra n g e o f ~100 ? t o 250 ?.
ad8344 rev. 0 | page 17 of 20 25 ?5 0 5 10 15 20 10 100 1000 04826-0-048 if loading ( ? ) 20log ?conversion gain ( d b) measured modeled 15 0 15 12 9 6 3 0 3 6 9 12 10 15 20 25 30 35 40 45 50 04826-0-049 if frequency (mhz) c o n ver sion ga in ( d b ) inp u t ip 3 and p 1 db (dbm) f i g u re 45. co nvers i on g a in v s . if l oad i n g f i g u re 46. co nvers i on g a in, input i p 3 , and p1db v s . if f r equenc y , f rf = 45 0 m h z low if f r equency operation 8 7 2 28.0 24.5 21.0 17.5 14.0 10.5 7.0 3 4 5 6 10 15 20 25 30 35 40 45 50 04826-0-050 if frequency (mhz) c o n ver sion ga in ( d b ) inp u t ip 3 and p 1 db (dbm) the ad8344 ma y be us e d do wn t o a r b i tra r il y lo w if f r eq uen - cies. the con v ersio n ga in, n o is e , a nd li n e a r i t y cha r ac t e r i st ics r e ma in q u i t e f l a t as if f r eq uen c y is r e d u ced , as in dic a t e d in f i gur e 46 a nd f i gur e 47. l a rg er val u e p u l l -u p ind u c t o r s need to be us e d a t the lo w e r if f r eq uen c ies. a 1 h ch ok e ind u c t o r w o u l d p r es en t a co mm on- m o d e lo adin g i m p e da n c e o f 63 ? a t a n if f r eq uen c y o f 10 mh z, s e ver e l y lo adin g do wn the mixer o u t p uts, r e d u ci n g co n v ersio n ga in, and s a cr if icin g o u t p u t p o w e r . a t lo w if f r eq u e n c ies, ch ok e ind u c t o r s o f s e v e r a l h u n d r e d h shou l d b e u s e d f o r bi a s i n g t h e i f output s . f i g u re 47. co nvers i on g a in, input i p 3 , and p1db v s . if f r equenc y , f rf = 89 0 m h z
ad8344 rev. 0 | page 18 of 20 evaluation board an evaluation board is available for the ad8344. the evaluation board is configured for single-ended signaling at the if output port via a balun transformer. the schematic for the evaluation board is presented in figure 48. table 5. evaluation boards configuration options component function default conditions r1, r2, r7, c2, c4, c5, c6, c12, c13, c14, c15 supply decoupling . jumpers or power supply decoupling resistors and filter capacitors. r1, r2, r7 = 0 ? (size 0603) c4, c6, c13, c14 = 100 pf (size 0603) c2, c5, c12, c15 = 0.1 f (size 0603) r3, r4 jumpers in single-ended if output circuit. 0 ? (size 0603) r6, c11 r bias resistor that sets the bias current for the mixer core. the capacitor provides ac bypass for r6. r6 = 2.43 k? (size 0603) c11 = 100 pf (size 0603) r8 jumper for pull down of the pwdn pin. r8 = 10 k? (size 0603) r9 jumper. r9 = 0 ? (size 0603) c3 rf input ac coupling . provides dc block for rf input. c3 = 100 pf (size 0402) c1 rf common ac coupling . provides dc block for rf input common connection. c1 = 100 pf (size 0402) c8 lo input ac coupling . provides dc block for the lo input. c8 = 100 pf (size 0402) c7 lo common ac coupling . provides dc block for lo input common connection. c7 = 100 pf (size 0402) sw1 power down. the part is on when the pwdn is connected to ground via sw1. the part is disabled when pwdn is connected to the positive supply (v s ) via sw1. t1 if output balun transformer . converts differential, high impedance if output to single-ended. when loaded with 50 ?, this balun presents a 200 ? load to the mixers collectors. the center tap of the pr imary is used to supply the bias voltage (v s ) to the if output pins. t1 = tc4-1w, 4:1 (mini-circuits) r11, z3, z4 r12, z1, z2 if output interface ifop, ifom. these positions can be used to modify the impedance presented to the if outputs. r11 = 0 ? (size 0603) z3, z4 = open r12 = 0 ? (size 0603) z1, z2 = open
ad8344 rev. 0 | page 19 of 20 04826-0-005 vplo locm loin comm vpd c pw d n exr b comm comm ifop ifom comm comm rfcm rfin vpmx ad8344 c1 100pf c3 100pf c6 100pf c7 100pf c8 100pf c5 0.1 f c4 100pf c2 0.1 f r2 0 ? r1 0 ? r7 0 ? r6 2.43k ? c11 100pf r10 0 ? r9 0 ? r3 0 ? r11 0 ? vpos vpos common power down rf input lo input z1 open z2 open r8 10k ? z3 open z4 open r4 0 ? t1 tc4-1w if output c14 100pf c15 0.1 f vpos sw1 c13 100pf c12 0.1 f f i gure 4 8 . e v a l ua tio n bo ar d schema ticsingle-ended if o u tput 04826-0-007 f i g u re 49. sing l e -e nded ev aluat i on b o a r d , co mpon ent s i de l a yout 04826-0-008 f i g u re 50. sing l e -e nded ev aluat i on b o a r d , co mpon ent s i de s ilk s c r e en
ad8344 rev. 0 | page 20 of 20 outline dimensions 1 0.50 bsc 0.60 max pin 1 indicator 1.50 ref 0.50 0.40 0.30 0.25 min 0.45 2.75 bsc sq to p v i e w 12 max 0.80 max 0.65 typ sea ting plane pin 1 indicator 1.00 0.85 0.80 0.30 0.23 0.18 0.05 max 0.02 nom 0.20 ref 3.00 bsc sq 1.65 1.50 sq * 1.35 bot t om vi e w 16 5 13 8 9 12 4 * compliant t o jedec st and ards mo-220-veed-2 except for exposed p ad dimension f i gure 51. 1 6 -l ead l e ad f r a m e ch ip s c a l e p a ck ag e [lfcs p ] 3 mm 3 m m b o d y (cp - 1 6 -3) di me nsio ns in m i l lim e t e r s ordering guide models temperature r a nge package desc ri ption package option branding ad8344acpz-r eel7 1 ?40c to +85c 16-lead lead fr ame ch ip scale package (lfcsp) cp-16-3 jha ad8344acpz-w p 1 , 2 ?40c to +85c 16-lead lead fr ame chip scale package (lfcsp) cp-16-3 jha AD8344-EVAL evaluation boar d 1 z = pb-free part. 2 w p = w a ff le pack . ? 2004 a n alo g devic e s, inc. all rig h ts res e rve d . t r ade m arks a n d re g i s - tered trade m arks are the property of their respective owners . d04826C0C 6/04(0)

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