nju7907 a -1- ver.0.7e monaural microphone amplifier general description package outline the NJU7907A is a monaural microphone amplifier ic including regulator for microphone capcel, pre-amplifier and line amplifier. the NJU7907A features low consumption current, wide dynamic range, wide operating voltage range, wide operating temperature and urtla small and thin package. it is suitable for microphone module, headset for conference system, automotive microphone for ecall, and any portable applications. features operating voltage 4.5 to 16v low consumption current wide dynamic range wide operating temperature cmos technology package outline epffp10-c4 block diagram NJU7907Auc4 c cup r bias r fb1 r fb2 v s =8v sigout gnd prein preout l inein fb v+ r l bias mic lineout ir ef gen n f
NJU7907A - 2 - pin configuration no. symbol function 1 preout pre-amplifier output terminal 2 prein pre-amplifier input terminal 3 nf noise filter terminal 4 gnd ground terminal 5 lineout line amplifier output terminal 6 nc no connect 7 v + power supply terminal 8 fb line amplifier feedback terminal 9 linein line amplifier input terminal 10 bias reference current setting terminal 2 1 10 9 8 6 7 3 4 5 bottom vie w top view 2 1 6 7 10 9 8 3 4 5
nju7907 a -3- absolute maximum rating (ta=25c) parameter symbol rating unit supply voltage v + 18 v power dissipation p d 340 note: eia/jedec standard test board (76.2x114.3x1.6mm, 2layer, fr-4) mounting mw maximum input voltage vimax 0.3 vrms operating temperature range topr -40 to +85 c storage temperature range tstg -40 to +125 c electrical characteristics (ta=25c, v s =8v, g v =37.8db, f=1khz unless otherwise specified) ? dc characteristics (rg=0 ? , r l =680 ? unless otherwise specified) parameter symbol test condition min. typ. max. unit operating voltage v s 4.5 8.0 16.0 v supply current1 i dd1 no signal - 4.85 6.0 ma supply current2 i dd2 r fb1 =0 ? ,r fb2 = - 220 320 a supply current3 i dd3 r l =0 ? - 28.0 50.0 ma reference current iref no signal 8.0 9.0 10.0 a output dc voltage v out no signal, lineout - 4.7 - v ? preamp characteristics (c in =1nf, r l =100k ? unless otherwise specified) parameter symbol test condition min. typ. max. unit voltage gain gv vin=50mvrms -0.8 -0.5 -0.2 db frequency response ? g f 1khz-10khz -0.5 0 0.5 db input capacitance ci - 1.0 - pf input resistance ri 200 - - m ? total harmonic distortion thd vin=100mvrms bw=400hz to 30khz - 0.1 0.5 % output noise voltage 1 v no1 weighted-a, c nf =none - -108 - dbv output noise voltage 2 v no2 weighted-a, c nf =1nf - -112 - dbv output noise voltage 3 v no3 prein -> lineout weighted-a, c nf =none - -68 -63 dbv output noise voltage 4 v no4 prein -> lineout weighted-a, c nf =1nf - -73 -68 dbv ? lineamp characteristics (rg=0 ? , r l =680 ? unless otherwise specified) parameter symbol test condition min. typ. max. unit maximum output voltage v om output, thd=3% 1.8 2.1 - vrms voltage gain g v vin=10mvrms 37.3 37.8 38.3 db total harmonic distortion thd vo=1.6vrms bw=400hz to 30khz - 0.1 0.5 % output noise voltage v no weighted-a - -78 -72 dbv output resistance ro - 5 10 ? input resistance ri 60 100 130 k ? ripple rejection rr v ripple =0.5vrms prein lineout 25 40 - db
NJU7907A - 4 - measurement circuit 1. dc characteristics 2. pre-amplifier characteristics 3. line amplifier characteristics 4. ripple rejection characteristics vout n f 22n 6.8k 390 30k v s =8v gnd prein preout l inein fb v+ 680 bias lineout 22n 100k v ~ 1n vin ir ef gen off :v no1 1n ~ 22n 6.8k 390 30k v s =8v gnd prein preout linein fb v+ 680 bias 1n lineout a a i dd1, i dd3 i dd2 v v out ir ef gen n f on :i dd3 off :i dd1 , i dd2 6.8k 390 fb bias 22n 30k gnd prein preout l inein v+ 680 1n lineout vout v ~ 8v v ripple sigout ir ef gen n f ~ 6.8k 390 30k v s =8v gnd preout l inein fb v+ 680 bias lineout 22n vin vout prein v ~ ir ef gen n f ~
nju7907 a -5- terminal description no. symbol function equivalent circuit voltage 1 2 preout prein pre-amplifier output terminal pre-amplifier input terminal 0.7v 0v 3 nf noise filter 1.2v 4 7 gnd v + ground terminal power supply terminal v+ gnd 0v 4.7v 5 lineout line amplifier output terminal 4.7v v+ 400 100 prein preout nf v+ 620k 400 12k lineout 200
NJU7907A - 6 - 8 9 10 fb linein bias line amplifier feedback terminal line amplifier input terminal reference current setting terminal 60mv 60mv 60mv 400 v+ fb linein bias 400 100k
nju7907 a -7- application circuit (g v =37.8db) (g v =23.9db) 22n 30k 1.8k 30k v s =8v sigout gnd prein preout l inein fb v+ 680 bias lineout ir ef gen n f mic 1n mic 22n 6.8k 390 30k v s =8v sigout gnd prein preout l inein fb v+ 680 bias lineout ir ef gen n f 1n
NJU7907A - 8 - application note design note: 1. feeding resistor r l range is 600 ? to 2.2k ? . set by operating voltage and other electrical characteristics. 2. output dc voltage is set by r bias. v r is voltage of r bias. v r = (r fb1 /(r fb1 +r fb2 )) ? vout vout : output dc voltage r bias = v r /iref iref : reference current output dc voltage is calculated with output voltage range. (see note.4) 3. total gain is determined with gv= 20log(r fb1 +r fb2 )/ r fb1 ) [db] voltage gain range is 24db to 40db [@1khz] 4. output voltage range is determined with dc range =v s - (vhsat+vlsat) vhsat : high side minimum saturation voltage vhsat =(i dd2+ i rf ) ? r l i rf : current for feedback resistor.[r fb1, r fb2] i rf =vo/(r fb1+ r fb2 ) vo= output dc voltage vlsat : low side minimum saturation voltage (approximately 1.8v @25deg.) ex. v s =8v, vo=4.7v, r l =680 ? , r fb1 =390 ? , r fb2 =30k ? , vlsat=1.8v i rf =4.7v/(390 ? +30k ? )=154.7ua vhsat =(220a + 154.7a) ? 680=254.8mv dc range =8v-(254.8mv +1.8v)=5.95v p-p. v s sigout gnd prein preout linein fb v+ r l c cup bias r bias r fb1 mic r fb2 lineout ir ef gen nf i rf iref v s gn d vlsat vhsat output voltage range output dc voltage
nju7907 a -9- 5. supply current. i dd1 =(v s - v out )/r l r l: feeding resistor. 6. maximum load capacitance c lmax <1,000pf 7. cut off frequency is determined with fc=1/(2 ? c cup (r in +r bias ) r in :line amp input resistance=100k ?
NJU7907A - 10 - package dimension . [caution] the specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. the application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights.
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