NJM2772 - 1 - low-voltage headphone amplifier for portable-audio general description package outline the NJM2772 is a low voltage headphone amplifier for portable audio. the NJM2772 includes mute circuit, center amplifier and beep input, reduce the external parts, standby circuit and center amplifier with on/off, applies to low current consumption. the mute function reduces the turn-noise at standby mode. the NJM2772 is suitable for portable md, cd, and others portable audio system with headphone amplifier. features operating voltage v + =1.8-4.5v operating current 1.2ma typ. @center amp. off 2.0ma typ. @center amp. on low standby current 18 a typ. high output power 6mwmin. @r l =16 ? , thd=10% fixed gain 11.5db typ. package outline ssop14 bipolar technology pin configuration & block diagram 1 2 3 4 14 13 12 11 outa outc 10 pa-a 5 6 7 9 stby 8 vref ina mutetc v + gnd vref + + inb beep outb dnc pa-c pa-b mute centersw note)dnc(14pin):do not connect NJM2772v pin function 1.stby 2.ina 3.centersw 4.v ref 5. beep 6.inb 7.mute 8.mutetc 9.outb 10.gnd 11.outc 12. v + 13.outa 14.dnc
NJM2772 - 2 - absolute maximum ratings (ta=25 c) parameter symbol ratings unit supply voltage v + 5v power dissipation p d (ssop14) 300 mw operating temperature range topr -20 to +75 c storage temperature range tstg -40 to +125 c recommended operating conditiions (ta=25 c) parameter symbol min. typ. max. unit operating voltage range v + 1.8 2.3 4.5 v electrical characteristics (v + =2.3v,rg=600 ? ,r l =16 ? ,f=1khz,stby-off,mute-off,ca-on,ta=25 c) parameter symbol test condition min. typ. max. unit i cc 1 standby-on,mute-on - 18 26 a i cc 2 no signal, ca-off - 1.2 2.0 ma i cc 3 no signal - 2.0 4.0 ma i cc 4p o =0.5mw+0.5mw,ca-off - 5.8 - ma i cc 5p o =0.5mw+0.5mw - 11.7 - ma icc6 p o =0.1mw+0.1mw,ca-off - 3.0 - ma operating current i cc 7p o =0.1mw+0.1mw - 5.9 - ma reference voltage v ref no signal 0.70 0.75 0.80 v voltage gain g v v in =-30dbv 10.5 11.5 12.5 db p o 1 thd=10% 6.0 8.0 - output power p o 2v + 1=1.8v,thd=10% 3.0 4.0 - mw total harmonic distortion thd v in =-30dbv - 0.1 0.5 % output noise voltage v no a-weighted - -98 (12.6) -94 (20) dbv ( vrms) closs-talk ct v in =-30dbv,vo=-18.5dbv - -40 -24 db mute level mute mute-on,v in =-30dbv,a-weighted - -95 -80 dbv beep output voltage v beep beep-in=2vpp -55 -50 -45 dbv supply voltage rejection ratio svr v + =1.8v+0.1vrms:1khz 65 70 - db control terminal characteristics parameter symbol test condition min. typ. max. unit h level input voltage v ih stby(1pin),csw(3pin),mute(7pin) 0.8 - v + v l level input voltage v il stby(1pin),csw(3pin),mute(7pin) 0 - 0.3 v h level input voltage v bh beep(5pin) 0.8 - v + v l level input voltage v bl beep(5pin) 0 - 0.3 v
NJM2772 - 3 - control terminal explantion ? stby (1pin) parameter control signal status standby on l ic is standby. standby off h ic is active. ? center-sw (3pin) parameter control signal status center amp. on l center amp. is active. can operate output coupling capacitor less. center amp. off h when output coupling capacitor is used, realize low current con- sumption to be center amp. off. ? mute (7pin) parameter control signal status mute on h ic output no signal. mute off l ic output the signal. application circuit 1) center amp. on mode 1 2 3 4 14 13 12 11 outa outc 10 pa-a 5 6 7 9 stby 8 vref ina 0.47uf 16 ? mutetc 0.47uf v + 0.1uf 16 ? stby off stby on gnd vref 47uf + + inb 0.47uf beep outb dnc pa-c pa-b mute on mute off mute centersw center off center on
NJM2772 - 4 - application circuit 2) center amp. off mode 1 2 3 4 14 13 12 11 outa 10 pa-a 5 6 7 9 stby 8 vref ina 0.47uf 16 ? mutetc 0.47uf v + 0.1uf 16 ? stby off stby on gnd vref 47uf + + inb 0.47uf beep outb dnc pa-c pa-b mute on mute off mute centersw center off center on note) when the beep terminal (5pin) is useless, short to gnd. [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.
|
