FUNCTIONAL DESCRIPTION

Pin

Function

Description

1, 2

INPUTS

The input stage is a high impedance type also capable of operation in single ended mode

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

Supply Voltage.

4CD

The TDA7391 is equipped with a diagnostic circuitry able to detect the clipping in the

Output Signal (distortion = 10%).

The CD pin (open collector) gives out low level signal during clipping.

5, 7

OUTPUTS

The output stage is a bridge type able to drive loads as low as 3.2

Ω.

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.

8

STAND-BY

The device features a ST-BY function which shuts down all the internal bias supplies

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.

10

SYNC

required to bias the amplifier.

11

MUTE

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).

TDA7391

4/8