NJU8713 -1- ver.2004-06-02 2v operation switching driver for class d amplifier general description the NJU8713 is a switching driver for a class d amplifier including separated power source terminals between input and output, beep and bpz (bipolar zero) output circuits. it converts 1bit digital signal input, such as pwm or pdm signal, to an analog signal output through a simple external lc low-pass filter. the NJU8713 realizes very high power-efficiency because of the class d operation. therefore, it is suitable for portable audio set and others. features 2-channel 1bit audio signal input standby(hi-z), bpz control internal bpz charger beep function operating voltage : 1.7v to 2.7v driving voltage : 1.7v to v dd cmos technology package outline : ssop14 block diagram package outline pin configuration mc k v ss in 1 en 1 v sso beep v dd in 2 en 2 v sso 1 2 3 4 5 14 13 12 11 10 6 7 9 8 out 1 v ddo out 2 v ddo en 1 en 2 beep in 2 in 1 mck out 1 out 2 bpz output bpz output output control v ss v dd v sso v ddo NJU8713v
NJU8713 - 2 - ver.2004-06-02 terminal description no. symbol i/o function 13 v dd - operation power supply, v dd =2v 2 v ss - operation power gnd, v ss =0v 7 8 v ddo - driving power supply, v ddo =2v terminal no.7 and no.8 should be connected to the same electric potential. 5 10 v sso - driving power gnd, v sso =0v terminal no.5 and no.10 should be connected to the same electric potential. 1 mck i master clock input terminal the condition of the data input terminal is fetched with the rising edge of this signal. 4 11 en 1 en 2 i output control terminal output circuit is selected by the condition of this terminal. 3 12 in 1 in 2 i audio signal input terminal 1-bit audio signal inputs into this terminal. 14 beep i beep signal input terminal beep signal inputs into this terminal. 6 9 out 1 out 2 o output terminal ? when output terminal selects audio signal, in 1 terminal input data outputs from out 1 terminal and in 2 terminal input data outputs from out 2 terminal. ? when output terminal selects beep signal, beep terminal input data outputs from out 1 and out 2 terminals. input terminal structure v dd v ss input terminal inside circuit
nju3555 NJU8713 -3- ver.2004-06-02 functional description (1) signal output pwm signals of l channel and r output from out 1 and out 2 terminals respectively. these signals are converted to analog signal by external 2nd-order or over lc filter. the output driver power supplied from v ddo and v sso are required high response power supply against voltage fluctuation like as switching regulator because output t.h.d is effected by power supply stability. (2) master clock master clock (mck) synchronizes the audio signal inputs (in 1 and in 2 ). the setup time and the hold time should be kept in the ac characteristics because in 1 and in 2 are fetched with the rising edge of mck. mck requires jitter-free or jitter as small as possible because the jitter downs s/n ratio. out 1 and out 2 occur the pop noise when mck is stopped in operation without standby mode. therefore, the standby mode should be set before mck stop. (3) output control output circuit is selected by the conditions of en 1 and en 2 terminals. en 2 en 1 output state of out 1 & out 2 0 0 standby(high impedance) 0 1 audio signal output 1 0 bpz output 1 1 beep signal output (4) beep function the beep signal must be input before the rising edge of en 2 signal and must be stopped after the falling edge of en 2 signal. en 1 en 2 mc k beep bee p si g nal out p ut audio signal output audio signal output
NJU8713 - 4 - ver.2004-06-02 (5) bpz function bpz function operates to charge the external ac coupling capacitor for the bpz level which is a point of the analog signal common. be sure to input sound-less data to in 1 and in 2 in busy of the bpz function. at this time, the sound-less signal must be input before the rising edge of en 2 signal and must be continue after the falling edge of en 2 signal. the charging time is in proportion to the capacity value of the external ac coupling capacitor. en 1 en 2 mc k in 1 , in 2 bpz out p ut standby standby audio signal output sound-less data audio data
nju3555 NJU8713 -5- ver.2004-06-02 absolute maximum ratings (ta=25 c) parameter symbol rating unit operation supply voltage v dd -0.3 to +4.0 v driving supply voltage v ddo -0.3 to +2.7 v input voltage vin -0.3 to v dd +0.3 v operating temperature topr -40 to +85 c storage temperature tstg -40 to +125 c power dissipation ssop14 p d 300 mw power supply voltage condition - v dd v ddo v note 1) all voltage values are specified as v ss =v sso =0v. note 2) if the lsi is used on condition beyond the absolute maximum rating, the lsi may be destroyed. using lsi within electrical characteristics is strongly recommended for normal operation. use bey ond the electrical characteristics conditions will cause malfunction and poor reliability. note 3) decoupling capacitors should be connected between v dd -v ss and v ddo -v sso due to the stabilized operation. electrical characteristics (ta=25 c, v dd =v ddo =2.0v, v ss =v sso =0.0v, load impedance=32 ? , f s =44.1khz, unless otherwise noted) parameter symbol conditions min. typ. max. unit v dd supply voltage v dd 1.7 2.0 2.7 v v ddo supply voltage v ddo 1.7 2.0 v dd v bpz driving voltage v bpz load operating mck=256f s in 1 , in 2 =32f s duty50% v ddo /2-0.2 v ddo /2 v ddo /2+0.2 v output driver high side resistance r h v out =v ddo -0.1v - 1.5 2 ? output driver low side resistance r l v out =0.1v - 1.5 2 ? beep high side current i bh v out =v ddo -1v 20 50 150 ua beep low side current i bl v out =1v 20 50 150 ua operating current at standby i st stopping mck, in 1 , in 2 , beep - - 1 ua i dd - 0.05 0.1 operating current at no input signal i ddo no-load operating in 1 , in 2 =32f s mck=256f s - 0.6 1.2 ma v ih 0.7v dd - v dd v input voltage v il 0 - 0.3 v dd v input leakage current i lk - - 1 ua
NJU8713 - 6 - ver.2004-06-02 timing characteristics ? audio signal input (ta=25 c, v dd =v ddo =2.0v, v ss =v sso =0.0v, unless otherwise noted) parameter symbol conditions min. typ. max. unit mck frequency f mcki 8 - 25 mhz mck pulse width (h) t mckh 12 - - ns mck pulse width (l) t mckl 12 - - ns in 1 ,in 2 setup time t ds 20 - - ns in 1 ,in 2 hold time t dh 20 - - ns beep frequency f beep 0.1 - 20 khz note 4) t mcki shows the cycle of the mck signal. ? output control signal input (ta=25 c, v dd =v ddo =2.0v, v ss =v sso =0.0v, unless otherwise noted) parameter symbol conditions min. typ. max. unit rise time t er - - 50 ns fall time t ef - - 50 ns switching time t ed 100 ns note 5) all timings are based on 30% and 70% voltage level of v dd . t mckh t ds t dh mc k in 1 , in 2 t mckl t mcki t e f en 1 t er t ed en 2 0.9v dd 0.5v dd 0.1v dd 0.1v dd 0.9v dd 0.5v dd
nju3555 NJU8713 -7- ver.2004-06-02 application circuit ? stereo otl application example ? 1 channel btl application example note 6) de-coupling capacitors must be connected between each power supply pin and gnd pin. note 7) the power supply for v ddo requires fast driving response performance such as a switching regulator for t.h.d. note 8) the bigger capacitor value of external ac-coupling capacitors realize better low frequency response characteristics. in addition, esr(equivalent series resistance) should be low. note 9) the above circuit shows only application example and does not guarantee the any electrical characteristics. therefore, please consider and check the circuit carefully to fit your application. NJU8713 in 1 out 1 output control en 1 out 2 audio signal master cloc k mck beep signal in 2 beep en 2 headphone 32 ? 0.22uf 100uh 220uf 1k ? 0.22uf 100uh 220uf 1k ? 3 12 14 4 11 1 6 9 v ddo 2.2uf v sso 7 5 v ddo 2.2uf v sso 8 10 100uf switching regulato r 2.2uf 13 logic powe r v dd v ss 2 2.2uf 10uf a914by-101m NJU8713 in 1 out 1 out 2 audio signal in 2 speaker 32 ? 0.22uf 100uh 0 .22uf 100uh 6 9 3 12 v ddo 2.2uf v sso 7 5 v ddo 2.2uf v sso 8 10 100uf switching regulato r 2.2uf output control en 1 master cloc k mck beep en 2 14 4 11 1 13 logic power v dd v ss 2 2.2uf 10uf a914by-101m ? a914by-101m is manufactured by toko, inc. for further information, please refer to its technical papers. ? a914by-101m is manufactured by toko, inc. for further information, please refer to its technical papers. a914by-101m a914by-101m
NJU8713 - 8 - ver.2004-06-02 [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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