NJM2761 -1- audio limiter general description the NJM2761 is an audio limiter for speaker protection. the limit level is adjustable by external resistor. it is suitable for pc, potable audio and others. features wide operating voltage +2.7v to +13.0v variable limit level by external resistor 0.2 to1v low output noise -90dbv max. bipolar technology package outline msop10 (tvsp10)* ssop14 *meet jedec mo-187-da / thin type block diagram ? ? ? ? package outline vcc int sense outb outa inb ina vref sw NJM2761rb2 msop10 (tvsp10) NJM2761 v (ssop14)
NJM2761 - 2 - pin configuration msop10 (tvsp10) ssop14 1. v+ 2. outa 3. ina 4. int 5. vref 6. nc 7. nc 8. nc 9. nc 10. sence 11. sw 12. inb 13. outb 14. gnd 1. v+ 2. outa 3. ina 4. int 5. vref 6. sence 7. sw 8. inb 9. outb 10. gnd 14 13 12 11 10 1 2 3 4 5 6 7 9 8 10 9 8 7 6 1 2 3 4 5
NJM2761 -3- absolute maximum rating (ta=25 c) parameter symbol ratings unit supply voltage v + 14 v power dissipation p d 320(msop10 (tvsp10)) 300(ssop14) mw operating temperature range t opr -20 to +75 c storage temperature range t stg -40 to +125 c electrical characteristics power supply (ta=25 c, v + =5v unless otherwise specified) parameter symbol test condition min. typ. max. unit operating voltage v + - 2.7 5.0 13.0 v operating current i cc no signal - 1.5 2.0 ma reference voltage vref no signal 2.2 2.5 2.7 v ac characteristics (ta=25 c, v + =5v, v in =1vrms/f=1khz, rsense=20k ? , bw=400-30khz unless otherwise specified) parameter symbol test condition min. typ. max. unit limit level 1 g lim1 150 200 250 mvrms limit level 2 g lim2 v + =13v,rsense=4k ? ,v in =2vrms 0.7 1.0 1.3 vrms limit off g off sw=2v 0.9 1.0 1.1 vrms output noise v no r s =0 ? , a-weighting, - -100 (10) -90 (31.6) dbv ( vrms) total harmonic distortion thd+n - - 1 % cross talk ct - - -70 db ripple rejection rr v ripple =100mvrms, f=1khz - - -70 (316) dbv ( vrms) control characteristics (ta=25 c, v + =5v unless otherwise specified) parameter symbol test condition min. typ. max. unit low level input voltage v il - - - 0.5 v high level input voltage v ih - 2.0 - - v control terminal explanation sw(msop10 (tvsp10)):7pin, ssop14:11pin) mode status note limiter on l limiter is active. limiter off h limiter is not active.
NJM2761 - 4 - terminal description no , msop10(ssop14) symbol function equivalent circuit voltage 1 v+ power supply terminal - 2 9(13) outa outb ach output terminal bch output terminal v+/2 3 8(12) ina inb ach input terminal bch input terminal v+/2 4 int smoothing capacitor connection terminal 0.7v 5 vrefin reference voltage stabilizing capacitor connection terminal v+/2 outa outb 100 ina inb 48k 96k 1k int 400 ? vrefin 300k 300k 300k
NJM2761 -5- terminal description no. msop10(ssop14) symbol function equivalent circuit voltage 6(10) sense resister connection terminal for limit level setting 0v 7(11) sw limiter on/off switch - 10(14) gnd ground terminal - sw 150k 270k sense 12k
NJM2761 - 6 - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ( ( ( ( ( ( ( (
) ) ) ) ) ) ) ) ? ? <
? ? <
? ?<
? ? <
? ? <
? ? <
? ? ? ? ? ? ? ? ? ? <
y y y y t t t t ? ? ? ?
application circuit msop10 (tvsp10) ssop14 * the limit level is twice as much as set point when a signal is input into a either one channel of ach or bch. * for the above reason, monaural signal should input both ina and inb. r sense =4000/vlim[ohm] vlim: limit level(vrms) limit range: 200mvrms to 1vrms (20k to 4kohm) 10 9 8 7 6 outa int ina gn d vref sens e s w inb outb 0.22 f v+ 0.22f 1f 0.22f 0.22f 1f 1 2 3 4 5 v+ r sense 0.022f
NJM2761 -7- typical characteristics 0 0.5 1 1.5 2 051015 v + - icc vcc[v] v + =5v,no-signal,limiter=on,rsense=20k ? icc[ma] 0 0.5 1 1.5 2 -20 0 20 40 60 80 icc-temperature icc[ma] temperature [c o ] v + =5v,no-signal,limiter=on,rsense=20k ? 0.01 0.1 1 0.01 0.1 1 limit response-v + output[vrms] input[vrms] vin=0dbv,limiter=on,rsense=20k ? v + =13.0v v + =2.7v v + =5.0v 0.01 0.1 1 10 0.0001 0.001 0.01 0.1 1 vom thd[%] input[vrms] f=1khz,limiter=off,rsense=20k ? v + =2.7v v + =5.0v v + =13.0v 0.01 0.1 1 0.01 0.1 1 limit response-rsense output [vrms] input[vrms] v + =5v,f=1khz,limiter=on rsense=4k rsense=8k rsense=20k 0.01 0.1 1 0.01 0.1 1 limit response-temperature output [vrms] input[vrms] -20c o 25c o 75c o v + =5v,vin=0dbv,limiter=on,rsense=20k ?
NJM2761 - 8 - typical characteristics [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. -100 -80 -60 -40 -20 0 100 1000 10000 ripple rejection ripple[dbv] frequency[hz] v + =5v,vripple=100mvrms,limiter=on -20c o 25c o 75c o 0.01 0.1 1 10 0.001 0.01 0.1 1 thd-vcc thd[%] input[vrms] f=1khz,limiter=on,rsense=20k ? v + =2.7v v + =5.0v v + =13.0v 0.01 0.1 1 10 0.001 0.01 0.1 1 thd-temperature thd[%] input[vrms] v + =5v,vin=0dbv,limiter=on,rsense=20k ? -20c o 25c o 75c o -100 -95 -90 -85 -80 -75 -70 -65 -60 100 1000 10000 cross talk cross talk[db] frequency[hz] v + =5v,vin=0dbv,limiter=on,rsense=20k ? -20c o 25c o 75c o
|
