technical data IL34119 low power audio amplifier ordering information IL34119n pl ast i c IL34119d soic t a = -10 to 7 0 c for all packages the IL34119 i s a l o w power audi o am pl i f i e r i n t e grat ed ci rcui t i n t e nded (pri m a ri l y ) for t e l e phone appl i cat i ons, such as i n speakerphones. it provi des di fferent i a l speaker out put s t o m a xi m i ze out put swi ng at l o w suppl y vol t a ges (2.0 vol t s m i ni m u m ) . c oupl i ng capaci t o rs t o t h e speaker are not requi red. open l oop gai n i s 80 db , and t h e cl osed l oop gai n i s set wi t h t w o ext e rnal resi st ors. a c h i p di sabl e pi n perm i t s poweri ng down and/ or m u t i ng t h e i nput si gnal . the IL34119 i s avai l a bl e i n a st andard 8 pin dip or a surface m ount package. ? w i de operat i ng suppl y vol t a ge r a nge (2-16 vol t s ) - al l o ws tel e phone li ne powered appl i cat i ons ? low qui e scent suppl y c u rrent for b a t t e ry powered appl i cat i ons ? c h i p di sabl e input t o power down t h e ic ? low power down quiescent current ? drives a w i de range of speaker loads (8-100 ? ) ? output power exceeds 250 m w with 32 ? speaker ? low tot a l harm oni c di st ort i on ? gai n adjust abl e from <0 db t o >46 db for voi ce b a nd ? r e qui res few ext e rnal c o m ponent s pin assignment simplified block diagram * = opt i onal differen tial gain = 2 x r f r i 1
IL34119 pin description p i n s y m b o l d e s c r i p t i o n 1 c d c h i p di sabl e - di gi t a l i nput . a logi c ?0? (<0.8 v) set s norm a l operat i on. a logi c ?1? ( 2.0 v) set s t h e power down m ode. input i m pedance i s nom i n al l y 90 k ? . 2 fc 2 a capaci t o r at t h i s pi n i n creases power suppl y reject i on, and affect s t u rn-on t i m e. thi s pi n can be l e ft open i f t h e cap acitor at fc1 is sufficient. 3 f c 1 anal og ground for t h e am pl i f i e rs. a 1.0 f cap acito r at th is p i n (with a 5 . 0 f capaci t o r at pi n 2) provi des 52 db of power suppl y reject i on. turn-on t i m e of t h e circuit is affected by the capacitor on this pi n. this pin can be used as an alternate i nput . 4 v in am pl i f i e r i nput . the i nput capaci t o r and resi st or set l o w frequency rol l o ff and i nput i m pedance. the feedback resi st or i s connect ed t o t h i s pi n and vo1. 5 v o 1 am p lifier ou tp u t # 1 . th e d c lev e l is (v cc - 0.7 v)/ 2 . 6 v cc dc suppl y vol t a ge (+2.0 t o +16 vol t s ) i s appl i e d t o t h i s pi n. 7 gnd ground pi n for t h e ent i r e ci rcui t . 8 v o 2 am pl i f i e r out put #2. thi s si gnal i s equal i n am pl i t ude, but 180 out of phase wi t h t h at at vo1 . th e d c lev e l is (v cc - 0.7 v)/ 2 . design guidelines general the IL34119 i s a l o w power audi o am pl i f i e r capabl e of l o w vol t a ge operat i on (v cc = 2.0 v m i ni m u m ) such as t h at encount ered i n l i n e-powered speakerphones. the ci rcui t provi des a di fferent i a l out put (vo1-vo2) t o t h e speaker to m a xim i ze the ava i l a bl e vol t a ge swi ng at l o w v o ltag e s. th e d i fferen tial g a in is set b y two ex tern al resi st ors. pi ns fc 1 and fc 2 al l o w cont rol l i ng t h e am ount of power suppl y and noi se reject i on, as wel l as provi di ng al t e rnat e i nput s t o t h e am pl i f i e rs. the c d pi n perm i t s poweri ng down t h e ic for m u t i ng purposes and t o conserve power. amplifiers r e ferri ng t o t h e bl ock di agram , t h e i n t e rnal confi gurat i on consi s t s of t w o i d ent i cal operat i onal am pl i f i e rs. am pl i f i e r #1 has an open-l oop gai n of 80 db (at f 100 hz), and t h e cl osed l oop gai n i s set by external resistors r f and r i . th e am p lifier is u n ity gai n st abl e , and has a uni t y gai n frequency of approxi m a t e l y 1.5 m h z. in order t o adequat e l y cover t h e t e l e phone voi ce band (300-340 hz), a m a xi m u m cl osed l oop gai n of 46 db i s recom m e nded. am pl i f i e r #2 i s in tern ally set to a g a in o f -1 .0 (0 d b ). the out put s of bot h am pl i f i e rs are capabl e of sourci ng and si nki ng a peak current of 200 m a . the o u t p u t s can typ i cally swin g to with in 0.4 vol t s above ground, and t o wi t h i n 1.3 vol t s bel o w v cc , at the m a xi m u m current . the out put dc offset vol t a ge (vo1-vo2) i s pri m ari l y a funct i on of t h e feedback resistor (r f ), and secondari l y due t o t h e am pl i f i e rs? i nput offset vol t a ges. the i nput offset vol t a ge of t h e t w o am p lifiers will g e n e rally b e sim ilar fo r a p a rticu l ar ic, and therefore nearly cancel each other at the outputs. am pl i f i e r #1?s bi as current , however, fl ows out of v in (pi n 4) and t h rough r f , fo rcin g vo1 to sh ift n e g a tiv e b y an am ount equal t o [r f x i ib ]. vo2 is sh ifted p o s itiv e an equal am ount . the out put offset vol t a ge speci fi ed i n t h e electrical characteristics is m easured with the feedback resi st or shown i n t h e si m p l i f i e d b l ock di agram , and t h erefore t a kes i n t o account t h e bi as current as wel l as in tern al o ffset v o ltag e s o f th e am p lifiers. th e b i as cu rren t is co n s tan t with resp ect to v cc . fc1 and fc2 power suppl y reject i on i s provi ded by t h e capaci t o rs (c 1 and c 2 i n t h e si m p l i f i e d b l ock di agram ) at fc 1 and fc 2. c 2 i s som e what dom i n ant at l o w frequenci e s, whi l e c 1 i s dom i n ant at hi gh frequenci e s. the regui red values of c1 and c2 depend on the conditions of each appl i cat i on. 2
IL34119 a line powered speakerphone, for exam ple, will req u i re m o re filterin g th an a circu it p o w ered b y a well requl at ed power suppl y . the am ount of reject i on i s a funct i on of t h e capaci t o rs, and t h e equi val e nt i m pedance l ooki ng i n t o fc 1 and fc 2 (l i s t e d i n t h e el ect ri cal characteristics as r fc1 and r fc2 ). in ad d itio n to p r o v i d i n g filterin g , c1 an d c2 also affect th e tu rn -o n tim e o f th e circuit at power-up, since t h e t w o capaci t o rs m u st change up t h rough t h e i n t e rnal 50 k ? and 125 k ? resistors. chip disable the c h i p di sabl e (pi n 1) can be used t o power down t h e ic t o conserve power, or for m u t i ng, or bot h. w h en at a logi c ?0? (0 t o 0.8 vol t s ), t h e IL34119 i s enabl e d for norm a l operat i on. w h en pi n 1 i s at a logi c ?1? (2.0 to v cc vol t s ), t h e ic i s di sabl ed. if pi n 1 i s open, t h at i s equi val e nt t o a logi c ?0?, al t hough good desi gn pract i ce di ct at es t h at an i nput shoul d never be l e ft open. input i m pedance at pi n 1 i s a nom i n al 90 k ? . the power suppl y current (when di sabl ed) i s shown i n fi gure 1. m u t i ng, defi ned as t h e change i n di fferent i a l gai n from norm a l operat i on t o m u t e d operat i on, i s i n excess of 70 db . the t u rn-off t i m e of t h e audi o out put , from t h e appl i cat i on of t h e c d si gnal , i s <2.0 s, and t u rn on-t i m e i s 12-15 m s . b o t h t i m es are i ndependent of c 1 , c 2 , and v cc . w h en t h e IL34119 i s di sabl ed, t h e vol t a ges at fc 1 and fc 2 do not change as t h ey are powered from v cc . the out put s, vo1 and vo2, change t o a hi gh i m pedance condi t i on, rem ovi ng t h e si gnal from t h e speaker. if si gnal s from ot her sources are t o be appl i e d t o t h e out put s (whi l e di sabl ed), t h ey m u st be wi t h i n t h e range of v cc and ground. power dissipation fi gures 2-4 i ndi cat e t h e devi ce di ssi pat i on (wi t h i n the ic) for various com b inations of v cc , r l , and l o ad power.the m a xi m u m power whi c h can safel y be di ssi pat e d wi t h i n t h e IL34119 i s found from t h e fol l o wi ng equat i on: p d = (140 c - t a )/ ja where t a is th e o p e ratin g tem p eratu r e; and ja is the package th erm a l resistance (100 c/w for the standard dip package, and 180 c/w for the surface m ount package). the power di ssi pat e d wi t h i n t h e IL34119, i n a gi ven appl i cat i on, i s found from t h e fol l o wi ng eguat i on: p d = (v cc x i cc ) + (i rms x v cc ) - (r l x i rms 2 ). where i cc i s obt ai ned from fi gure 1; and i rms is the rms current at the load; and r l is the load resistance. fi gures 2-4, al ong wi t h fi gures 5-7 (di s t o rt i on curves), and a peak working load current of 200 m a , defi ne t h e operat i ng range for t h e IL34119. the operat i ng range i s furt her defi ned i n t e rm s of al l o wabl e l o ad power i n fi gure 8 for l o ad of 8.0 ? , 16 ? , and 32 ? . the left (ascending) portion of each of the three curves i s defi ned by t h e power l e vel at whi c h 10% di st ort i on occurs. the center flat portion of each curve is defined b y th e m a x i m u m o u t p u t cu rren t cap ab ility o f th e IL34119. the right (descending) portion of each curve is defi ned by t h e m a xi m u m i n t e rnal power di ssi pat i on of the ic at 25 c . at hi gher operat i ng be reduced according to the above equa tions. operating the device beyond the current and junction tem p erature lim its will degrade long term reliability. layout considerations norm al l y a snubber i s not needed at t h e out put of t h e IL34119, unl i k e m a ny ot her audi o am pl i f i e rs. however, the pc board layout, stray capacitances, and the m a nner in which the speaker wires are configured, m a y dictate ot herwi s e. general l y t h e speaker wi res shoul d be t w i s t e d t i ght l y , and be not m o re t h an a few i n ches i n l e ngt h. maximum ratings * s y m b o l p a r a m e t e r v a l u e u n i t v cc suppl y vol t a ge 1.0 t o +18 v i out m a xim u m output current at vo1, vo2 250 ma v in m a xi m u m i nput vol t a ge(fc 1 , fc 2, c d , v in ) - 1 . 0 tov cc +1.0 v v vo appl i e d out put vol t a ge t o vo1, vo2 when disabled -1.0 tov cc +1.0 v tst g st orage tem p erat ure r a nge -65 t o +150 c * m a xi m u m r a t i ngs are t hose val u es bey ond whi c h dam a ge t o t h e devi ce m a y occur. functional operation should be restricted to the reco m m e nded operating conditions. 3
IL34119 recommended operating conditions s y m b o l p a r a m e t e r m i n m a x u n i t v cc suppl y vol t a ge 2.0 16 v r l load im pedance 8.0 100 ? i l peak load c u rrent - 200 m a avd differential gain (5.0 khz bandwidth) 0 46 db vcd voltage @ cd (pin 1) 0 v cc v t a operat i ng tem p erat ure, al l pakage ty pes -10 +70 c thi s devi ce cont ai ns prot ect i on ci rcui t r y t o guard agai ns t dam a ge due t o hi gh st at i c vol t a ges or el ect ri c fi el ds. however, precautions m u st be taken to avoid applications of any voltage highe r than m a xim u m rated voltages to this hi gh-i m pedance ci rcui t . for proper operat i on, v in and v out shoul d be const r ai ned t o t h e range gnd (v in or v out ) v cc . unused i nput s m u st al way s be t i e d t o an appropri a t e l ogi c vol t a ge l e vel (e.g., ei t h er gnd or v cc ). unused out put s m u st be l e ft open. electrical characteristics (t a = -10 to +70 c, v cd = 0 v) symbol parameter test conditions guaranteed limits unit m i n m a x amplifiers (dc characteristics) v o output dc level (vo1, vo2) v cc =3.0 v, r l =16 ? r f = 75 k ? 0 . 7 5 1 . 7 5 v v oh out put hi gh level i out = -75 m a , v cc = 2.0 v 0.5 - v v ol out put low level i out = 75 m a , 2.0 v v cc 16 v - 0 . 5 5 v ? v o output dc offset voltage (vo1-vo2) v cc =6.0 v, r l =32 ? r f = 75 k ? - 2 0 0 2 0 0 m v i ib input b i as c u rrent @ vin v cc =6.0 v - 1600 na r fc1 equi val e nt r e si st ance @ fc 1 v cc = 6.0 v 100 220 k ? r fc2 equi val e nt r e si st ance @ fc 2 v cc = 6.0 v 18 40 k ? v ih m i ni m u m hi gh-level input vo ltag e 2 . 0 - v v il m a xi m u m low-level input vo ltag e - 0 . 8 v r cd input r e si st ance v cc = v cd = 16 v 45 50* 175 175* k ? (cont i nued) 4
IL34119 electrical characteristics (t a = -10 to +70 c, v cd = 0 v) symbol parameter test conditions guaranteed limits unit m i n m a x amplifiers (ac characteristics) r i ac input r e si st ance (v in ) 2 2 . 5 - m ? a vol1 open loop gai n (am p l i f i e r #1) f = 100 hz, v cc = 6.0 v, v fc2 = 2.65 v 60 80* - d b a v2 c l osed loop gai n (am p l i f i e r #2) f = 1.0 khz, v cc = 6.0 v, r l =32 ? - 0 . 3 5 + 0 . 3 5 db gb w gai n b a ndwi d t h product 1.125 - m h z p out3 p out12 output power v cc = 3.0 v, r l = 16 ? , thd 10%, v fc2 = 1.15 v v cc = 12.0 v, r l = 100 ? , thd 10%, v fc2 =12 v 55 400* - - mw thd tot a l harm oni c di st ort i on v cc = 6.0 v, r l = 32 ? , f = 1.0 khz, p out = 125 m w - 5 . 0 1.0* % psr r power suppl y r e ject i on v cc = 6.0 v, ? v cc = 3.0 v, c1 = , c 2 = 0.01 f 35 50* - d b gm t m u t i n g v cc = 6.0 v, f = 1.0 khz, c d = 2.0 v 50 70* - d b power supply i cc1 i cc2 m a xi m u m power suppl y current v cc =3.0 v, r l = ,c d=0.8v v cc =3.0 v, r l = ,c d=2.0v - - 5.0 4.0* 125 5.0* ma a * @25 c figure 1. power supply current figure 2. device dissipation 8.0 ? load 5
IL34119 figure 3. device dissipation 16 ? load figure 4. device dissipation 32 ? load figure 5. distortion versus power f = 1.0 khz , avd = 34 db figure 6. distortion versus power f = 3.0 khz , avd = 34 db figure 7. distortion versus power f = 1, 3.0 khz , avd = 12 db fig u re 8 . max i mum allowable load power 6
IL34119 n s u f f i x p l as t i c di p ( m s ? 00 1b a ) sy m b o l m i n m a x a 8. 51 10. 16 b 6. 1 7 . 1 1 c 5. 33 d 0. 36 0. 56 f 1. 14 1. 78 g h j 0 10 k 2. 92 3. 81 no t e s : l 7. 62 8. 26 1. d i m e n s i o n s ?a ?, ?b ? d o n o t i n cl u d e m o l d f l as h o r p r o t r u s i o n s . m 0. 2 0 . 3 6 m a x i m u m m o l d f l a s h o r p r o t r u s i o n s 0. 25 m m ( 0 . 010) p e r s i d e . n 0. 38 d su f f i x so i c (m s - 0 1 2 a a) sy m b o l m i n m a x a 4. 8 5 b 3. 8 4 c 1. 35 1. 75 d 0. 33 0. 51 f 0. 4 1 . 2 7 g h j 0 8 no t e s : k 0. 1 0 . 2 5 1. d i m e n s i o ns a a n d b d o no t i n c l ud e m o l d f l a s h o r p r ot r u s i on . m 0. 19 0. 25 2. m a x i m u m m o l d f l a s h o r p r o t r u s i o n 0. 15 m m ( 0 . 006) p e r s i d e p 5. 8 6 . 2 fo r a ; fo r b ? 0. 25 m m ( 0 . 010) p e r s i d e . r 0. 25 0. 5 1. 27 5. 72 d i me n s i o n , mm d i me n s i o n , mm 2. 54 7. 62 a b h c k c m j f m p g d r x 4 5 se a t i n g pl a n e 0 . 25 (0 . 0 10 ) m t -t - 1 8 4 5 l h m j a b f g d se a t i n g pl a n e n k 0 . 2 5 ( 0 .01 0 ) m t -t - c 1 8 4 5 7
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