TDA7370BV Datasheet, PDF (13/17 Pages) STMicroelectronics – QUAD POWER AMPLIFIER FOR CAR RADIO

TDA7370B
CLIPPING DETECTOR
WHAT IS NEEDED FOR A DEMONSTRATION
Figures 25 and 26 show an application using the
TDA7370B in combination with the SGS-THOM-
SON audioprocessor TDA7302.
The output clipping is recognized by the microproc-
essor (in this application it is simulated by a PC).
The detailed way to operate of the system is rep-
resented by the flow-chart of fig.24
- a XT or AT IBM compatible PC, supplied with
EGA card
- a SGS-THOMSON audioprocessor application disk
- a TDA 7302 + TDA7370B board
- a connector from audioprocessor board to PC
parallel port
The controller detects when the clipping is active _{GENERAL INFORMATION}
(minimun detection width fixed by a C29 = 12 nF
external capacitor), and reduces the volume (or ^{In the application shown in figures 25 and 26 the}
bass ) by steps of 2 dB (with a programmable
waiting time), until no more clipping is detected.
Then the controller waits for a programmable time
) _{before increasing the volume again by step of 2}
t(s ^{dB until clipping is again detected or the panel se-}
lected volume is reached.
uc _{Practical advantages of this application is a better}
d _{sound quality deriving from operation under no}
ro ^{clipping conditions, which also means the avail-}
ability of higher undistorted power.
Obsolete ^{Product(s) - Obsolete P Figure 24: Clipping Detector Control Routine}
TDA7302 audioprocessor works on PC XT or AT
IBM compatible.
Control is accomplished by serial bus ( S-bus or
I²C-bus or SPI bus) sent to the test board through
the PC parallel port.
The PC simulates the behaviour of the microproc-
essor in a real application (for example in a car
radio) and the buffer is necessary only in this ap-
plication for protecting the PC.
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