E-TDA7375V Datasheet, PDF (8/15 Pages) STMicroelectronics – 2 x 35W dual/quad power amplifier for car radio

TDA7375V
Figure 21. Total Power Dissipation and
Efficiency vs. Output Power
Figure 22. Total Power Dissipation and
Efficiency vs. Output Power
5 GENERAL STRUCTURE
5.1 High Application Flexibility
The availability of 4 independent channels makes it possible to accomplish several kinds of applications
ranging from 4 speakers stereo (F/R) to 2 speakers bridge solutions.
In case of working in single ended conditions the polarity of the speakers driven by the inverting amplifier
must be reversed respect to those driven by non inverting channels. This is to avoid phase inconveniences
causing sound alterations especially during the reproduction of low frequencies.
5.2 Easy Single Ended to Bridge Transition
The change from single ended to bridge configurations is made simply by means of a short circuit across
the inputs, that is no need of further external components.
5.3 Gain Internally Fixed to 20dB in Single Ended, 26dB in Bridge
Advantages of this design choice are in terms of:
■ componentsand space saving
■ output noise, supply voltage rejection and distortion optimization.
5.4 Silent Turn On/Off and Muting/Stand-by Function
The stand-by can be easily activated by means of a CMOS level applied to pin 7 through a RC filter.
Under stand-by condition the device is turned off completely (supply current = 1A typ.; output attenuation
= 80dB min.). Every ON/OFF operation is virtually pop free. Furthemore, at turn-on the device stays in
muting condition for a time determined by the value assigned to the SVR capacitor.
While in muting the device outputs becomes insensitive to any kinds of signal that may be present at the
input terminals. In other words every transient coming from previous stages produces no unplesantacous-
tic effect to the speakers.
5.5 STAND-BY DRIVING (pin 7)
Some precautions have to be taken in the definition of stand-by driving networks: pin 7 cannot be directly
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