TDA7372B 4 x 6w power amplifier for car radio advance data high power capability: 4x6w min/4 w @14.4v, 1khz, 10% 4x10w typ/2 w @14.4v, 1khz, 10% minimum external component count - internally fixed gain (40db) - no bootstrap capacitors - no external compensation st-by function (cmos compatible) mute function (cmos compatible) no audible pop during mute/st-by operations low supply self muting programmable turn on delay protections: ac output short circuit to gnd dc output short circuit to gnd and to v s at power on soft thermal limiter overrating chip temperature load dump voltage fortuitous open gnd reverse battery esd protection description the TDA7372B is a new technology class ab quad channels audio power amplifier in multiwatt15 package designed for car radio applications. thanks to the fully complementary pnp/npn out- put configuration the TDA7372B delivers a rail to rail voltage swing with no need of boostrap capacitors. this is advanced information on a new product now in development or undergoing evaluation. details are subject to change without notice. april 1995 block diagram multiwatt15 ordering number : TDA7372B 1/10
pin connection (top view) absolute maximum ratings symbol parameter value unit v s dc supply voltage 28 v v op operating supply voltage 18 v v peak peak supply voltage (t = 50ms) 50 v i o output peak current (not rep. t = 100 m s) 4 a i o output peak current (rep. f > 10hz) 3 a p tot power dissipation (t case = 85 c) 32 w t stg , t j storage and junction temperature -40 to 150 c thermal data symbol description value unit r th j-case thermal resistance junction-case max 2 c/w TDA7372B 2/10
electrical characteristics (refer to the test circuit; v s = 14.4v; r l = 4 w , t amb = 25c, f = 1khz, unless otherwise specified) symbol parameter test condition min. typ. max. unit v s supply range 8 18 v i d total quiescent drain current 150 ma p o output power r l = 4 w ; thd = 10% each channel 6 6.5 w r l = 2 w ; thd = 10% each channel 10 w d distortion r l = 4 w ; p o = 0.1 to 3w 0.08 0.5 % ct cross talk f = 1khz; r g = 0 f = 10khz; r g = 0 45 50 40 db db r in input impedance 35 k w g v voltage gain 40 db g v voltage gain match. 1 db bw bandwidth @ -3db 75 khz e no output noise voltage (*) r g = 0 300 m v svr supply voltage rejection r g = 0; f = 100hz 45 db asb stand-by attenuation 80 db i sb st-by current consumption vpin7 = 1.5v 100 m a i pin 7 st-by pin current play mode; vpin7 = 5v 50 m a output under short (max driving current under fault) 5ma v sb in st-by in threshold voltage 1.5 v v sb out st-by out threshold voltage 3.5 v a m mute attenuation 80 db v m in mute in threshold voltage 1.5 v v m out mute out threshold voltage 3.5 v (*) 22hz to 22khz TDA7372B 3/10
test and application circuit figure 1: p.c. board and components layout of the test and application circuit (1:1 scale) if high source resistance is present (e.g. passive audio controls) it might be necessary to add c = 470pf from each input pin to s-gnd to prevent instability phenomena. 10 m f c13 r2 TDA7372B 4/10
figure 2: quiescent drain current vs. supply voltage figure 4: output power vs supply voltage figure 6: distortion vs. output power figure 3: output power vs. supply voltage figure 5: output power vs. frequency vs.c out value figure 7: distortion vs. output power TDA7372B 5/10
figure 8: distortion vs. frequency figure 10: cross-talk vs. frequency figure 12: total power dissipation and efficiency figure 9: distortion vs. frequency figure 11: supply voltage rejection vs. frequency figure 13: total power dissipation and efficiency vs. output power p tot (w) p tot (w) p tot p tot TDA7372B 6/10
figure 14: tda7317 + 7372 application circuit. 10 m f TDA7372B 7/10
functional description function description general the TDA7372B is a quad channel single package audio power amplifier intended to reduce the mismatch in the electrical characteristics among the four different channels and to consistently drop the external component count. it contains four non inverting stages whose gain is internally fixed to 40db. output stage the output stage is a single ended type suitable to drine 4 w loads. it consists of a class ab fully complementary pnp/npn stages short circuit protected. a rail to rail output swing is achieved without need of boostrap capacitors. moreover, the external compensation is not necessary. st-by the device features a st-by function which shuts down the internal bias supplies when the st- by input is low. in st-by mode the amplifier sinks a small current (in the range of few m as). when the st-by pin is high the ic becomes fully operational. mute a mute function is also provided. this reduces the gain of the input stage to a level effectively eliminating any audio input influence on the output stage when the mute line is low. when the mute line is high the normal input path is restored. the device goes automatically is mute status when the supply voltage goes below the minimum allowed value. this prevents pop noises whenever the battery voltage drops below a fixed threshold. when the supply voltage rises to its nominal value the device recovers the play condition with a delay fixed by the c svr capacitor. thermal protection the thermal protection principle involves two different steps a) soft thermal limitation b) shutdown until the juntion temperature remains below a preset threshold, the i.c. will deliver the full power. once the threshold has been reached, the device automatically goes, into mute status. the play to mute transition is internally controlled so producing a soft muting without unpleasent effect. supposing the junction temperature does not reduce to safe levels a complete shutdown will occur. built-in short circuit protection reliable and safe operation in presence of: - ac short circuit to gnd - dc short circuit to gnd and to v s during power-on phase is assured by a built-in protection circuitry. the dc short protector acts in such a way to avoid the device is turned on (by st-by) when a dc short is present between out to gnd or out to v s . due to this reason it is necessary to introduce a proper delay on the st-by pin (expecially when it is driven by v s .) more over, as the involved circuitry is normally disabled when a current higher than 5ma is flowing into the st-by pin, it is important, in order not to disable it, to have the external current source driving the pin it self limited to 5ma. (figure 1 is showing relevant waveforms). figure 15: fault (dc short) waveforms TDA7372B 8/10
multiwatt15 package mechanical data dim. mm inch min. typ. max. min. typ. max. a 5 0.197 b 2.65 0.104 c 1.6 0.063 d 1 0.039 e 0.49 0.55 0.019 0.022 f 0.66 0.75 0.026 0.030 g 1.02 1.27 1.52 0.040 0.050 0.060 g1 17.53 17.78 18.03 0.690 0.700 0.710 h1 19.6 0.772 h2 20.2 0.795 l 21.9 22.2 22.5 0.862 0.874 0.886 l1 21.7 22.1 22.5 0.854 0.870 0.886 l2 17.65 18.1 0.695 0.713 l3 17.25 17.5 17.75 0.679 0.689 0.699 l4 10.3 10.7 10.9 0.406 0.421 0.429 l7 2.65 2.9 0.104 0.114 m 4.25 4.55 4.85 0.167 0.179 0.191 m1 4.63 5.08 5.53 0.182 0.200 0.218 s 1.9 2.6 0.075 0.102 s1 1.9 2.6 0.075 0.102 dia1 3.65 3.85 0.144 0.152 TDA7372B 9/10
information furnished is believed to be accurate and reliable. however, sgs-thomson microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of sgs-thomson microelectronics. specifications men- tioned in this publi cation are subject to change without not ice. this publication sup ersedes and replaces all information previously supplied. sgs-thomson microelectronics products are not authorized for use as critical components in life support dev ices or systems without ex- press written approval of sgs-thomson microelectronics. ? 1994 sgs-thomson microelectronics - all rights reserved multiwatt? is a registered trademark of the sgs-thomson microelectronics sgs-thomson microelectronics group of companies aust ralia - brazil - france - germany - hong kong - italy - japan - korea - malaysia - malta - morocco - the netherlands - singapore - spain - sweden - switzerland - taiwan - thaliand - united k ingdom - u.s.a. TDA7372B 10/10
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