TDA7391 Datasheet, PDF (4/8 Pages) STMicroelectronics – 35W BRIDGE CAR RADIO AMPLIFIER

TDA7391
FUNCTIONAL DESCRIPTION
Pin
Function
Description
The input stage is a high impedance type also capable of operation in single ended mode
1, 2
INPUTS
with one input capacitively coupled to the signal GND. The impedance seen by the
inverting and non inverting input pins must be matched.
3,9
+V_S
Supply Voltage.
The TDA7391 is equipped with a diagnostic circuitry able to detect the clipping in the
4
CD
Output Signal (distortion = 10%).
The CD pin (open collector) gives out low level signal during clipping.
The output stage is a bridge type able to drive loads as low as 3.2Ω.
5, 7
OUTPUTS
It consists of two class AB fully complementary PNP/NPN stages fully protected.
A rail to rail output voltage swing is achieved without need of bootstrap capacitors.
No external compensation is necessary.
6
GND
Ground.
The device features a ST-BY function which shuts down all the internal bias supplies
8
STAND-BY
when the ST-BY pin is low.
In ST-BY mode the amplifier sinks a small current (in the range of few µA).
When the ST-BY pin is high the IC becomes fully operational.
A resistor (R₂) has to be connect between pin 10 and GND in order to program the current
10
SYNC
that flows in the C₃ capacitor (pin 11). The values of C₃ and R₂ determine the time
required to bias the amplifier.
11
MUTE
The pin will have a capacitor (C₃) tied to GND to set the MUTE/STAND-BY time. An
automatic Mute during turn on/off is provided to prevent noisy transients.
Figure 3: P.C. Board and Component Layout of the Fig. 1 (1:1 scale).
4/8