NJU8719 -1- ver.2004-05-20 monaural btl output switching driver for class d amplifier general description the NJU8719 is a monaural btl output switching driver for class d amplifier. it converts 1bit digital signal input, such as pwm or pdm signal, to analog signal output with simple external lc low-pass filter. the NJU8719 realizes very high power-efficiency by class d operation. therefore, it is suitable for portable set with speaker. features 1-channel 1bit audio signal input monaural btl output standby(hi-z) control function operating voltage : 2.4v to 5.25v cmos technology package outline : ssop10 block diagram NJU8719v preliminary package outline pin configuration v dd in nc mc k stbyb v ss out p v ddo out n v ss 1 2 3 4 5 10 9 8 7 6 in stbyb v dd out n out p dead time generator mc k v ss v ddo v ss
NJU8719 - 2 - - 2 - ver.2004-05-20 terminal description no. symbol i/o function 1 v dd ? power supply, v dd =5v 2 in i 1-bit data input terminal 3 nc ? non connection 4 mck i master clock input terminal the condition of the data input terminal is fetched with the rising edge of this signal. 5 stbyb i standby control terminal (l:standby) 6 10 v ss ? power gnd and output gnd terminal: v ss =0v 7 out n o negative output 8 v ddo ? output power supply, v dd =5v 9 out p o positive output *v ss (terminal no.6,10) should be connected at a nearest point to the ic. *v dd (terminal no.1) and v ddo (terminal no.8) should be connected at a nearest point to the ic. *stbyb(terminal no.5) must be connected to v dd , when this terminal is not used. input terminal structure v dd v ss input terminal
nju3555 NJU8719 -3- ver.2004-05-20 functional description (1) signal output the out p and out n generate pmw output signal, which is converted to analog signal via external 2nd-order or higher lc filter. the NJU8719 drives a speaker by the btl output, and out p is a positive output and out n is a negative outputs. a switching regulator with a high response against a voltage fluctuation is the best selection for the v ddo, which is the power supply for output drivers. to obtain better t.h.d. performance, the stabilization of the power is required. (2) standby control function by setting the stbyb terminal to ?l?, the NJU8719 becomes standby condition. during standby condition, out p and out n are in hi-z. (3) master clock master clock (mck) synchronizes with the audio signal input (in). the setup time and the hold time should be kept in the ac characteristics because in is 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 p and out n occur the pop noise when mck is stopped in operation without standby mode. therefore, the standby mode should be set before mck stop.
NJU8719 - 4 - - 4 - ver.2004-05-20 absolute maximum ratings (ta=25 c) parameter symbol rating unit v dd -0.3 to +5.5 supply voltage v ddo -0.3 to +5.5 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 ssop10 p d 360* mw * : mounted on two-layer board of based on the jedec. note 1) all voltage values are specified as v ss =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) de-coupling capacitors should be connected between v dd -v ss and v ddo -v ss due to the stabilized operation. electrical characteristics (ta=25 c, v dd = v ddo =5.0v, v ss =0v, f s =44.1khz, unless otherwise noted) parameter symbol conditions min. typ. max. unit v dd ,v ddo supply voltage v dd 2.4 5.0 5.25 v output driver high side resistance r h v out =v ddo -0.1v - 0.5 1.5 ? output driver low side resistance r l v out =0.1v - 0.5 1.5 ? operating current at standby i st in, stbyb=0v no-load operating - - 1 a operating current at operating (mute signal input) i dd in=32f s mck=256f s no-load operating - 3.8 5.7 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 a
nju3555 NJU8719 -5- ver.2004-05-20 timing characteristics ? audio signal input (ta=25 c, v dd = v ddo =5.0v, v ss =0v, f s =44.1khz, unless otherwise noted) parameter symbol conditions min. typ. max. unit mck frequency f mcki - - 25 mhz mck pulse width (h) t mckh 12 - - ns mck pulse width (l) t mckl 12 - - ns in setup time t ds 20 - - ns in hold time t dh 20 - - ns ? output control signal input (ta=25 c, v dd = v ddo =5.0v, v ss =0v, f s =44.1khz, unless otherwise noted) parameter symbol conditions min. typ. max. unit rise time t up - - 50 ns fall time t dn - - 50 ns note 4) all timings are based on 30% and 70% voltage level of v dd . t mckh t ds t dh mc k in t mckl t dn t up stbyb 0.7v dd 0.7v dd 0.3v dd 0.3v dd
NJU8719 - 6 - - 6 - ver.2004-05-20 application circuit note 5) de-coupling capacitors must be connected between each power supply terminal and gnd terminal. note 6) the power supply for v ddo requires fast driving response performance such as a switching regulator for t.h.d.. note 7) 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. [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. mck(4) v dd (1) stbyb(5) in(2) v ss (10) v ss (6) v ddo (8) out n (7) out p (9) NJU8719 v dd 10 ? 1
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