May 1988

4

Philips Semiconductors

Product specification

TDA8421

PINNING

FUNCTIONAL DESCRIPTION

Input selector

The input to channel 1 (CH1) and channel 2 (CH2) is determined by the input selector. The selection is made from the

following AF input signals:

• IN1 L (pin 26); IN1 R (pin 28) or

• IN2 L (pin 1); IN2 R (pin 3)

Where IN1 is an internal input signal and IN2 an external input signal.

Mode selector

For each channel (CH1 and CH2) there is a mode selector which selects between stereo, sound A and sound B in the

event of bilingual transmission. Both mode selectors can be controlled independently.

Fig.2 Pinning diagram.