March 1991

4

Philips Semiconductors

Product specification

TDA8442

OPERATION

Write

Programming of the TDA8442 is performed using the format shown in Fig.3.

Acknowledge (A) is generated by the TDA8442 only when a valid address is received and the device is not in the

Control

Control is implemented by the instruction bytes POD (port output data) and DACX (digital-to-analogue converter control)

together with the corresponding data/control bytes (see Fig.4).

POD bit P1

If a logic 1 is programmed, the P1 output is switched on. If a logic 0 is programmed or after a power-down-reset, the P1

output is switched off (high-impedance state).

POD bit P2/P2N

If a logic 1 is programmed, the P2 output is switched off and the P2N output is switched on (LOW). If a logic 0 is

programmed or after a power-down-reset, the P2 output is switched on (LOW) and the P2N output is switched off.

DAX bits AX5 to AX0

The digital-to-analogue converter selected corresponds to the decimal equivalent of the two bits X1 and X0. The output

voltage of the selected DAC is programmed using bits AX5 to AX0, the lowest value being with all data AX5 to AX0 at

logic 0 or when power-down-reset has been activated.

Fig.3 TDA8442 programming format.

Fig.4 Control porgramming.