1998 May 27

6

Philips Semiconductors

Preliminary specification

Multi-purpose high-gain power amplifier

TDA8581

FUNCTIONAL DESCRIPTION

The TDA8581 is a multi-purpose power amplifier with four

amplifiers which can be connected in the following

configurations with high output power and low distortion (at

minimum quiescent current);

• Dual bridge-tied load (BTL) amplifiers

• Quad single-ended amplifiers

• Dual single-ended amplifiers and one bridge-tied load

amplifier.

The amplifier can be switched on (play or ‘mute’) and off

(‘standby’) by the MUTE and STANDBY pins (for

interfacing directly with a microcontroller). One-pin

operation is also possible by applying a voltage greater

than 8 V to the ‘standby’/’mute’/’on’ selection pin (pin 5) to

switch the amplifier in ‘on’ mode.

Special attention is given to the dynamic behaviour as

follows:

• Noise suppression during engine start.

• No plops when switching from ‘standby’ to ‘on’.

• Slow offset change between ‘mute’ and ‘on’ (controlled

by MUTE and STANDBY pins).

• Low noise levels, which are independent of the supply

voltage.

Protections are included to avoid the IC being damaged at:

• Over temperature: T > 150 °C.

• Short-circuit of the output pin(s) to ground or supply rail.

When short-circuited, the power dissipation is limited.

• A missing-current limiter which limits the maximum short

The dissipation and speaker current will be minimized

because the short-circuited amplifier is switched off.

The chip temperature is limited by the temperature

protection.

• ESD protection (Human Body Model 3000 V, Machine

Model 300 V).

• Energy handling. A DC voltage of 6 V can be connected

to the output of any amplifier while the supply pins are

short-circuited to ground. No high DC current will flow

from the supply pins of the amplifier.

• Reverse battery only with protection diode added.

Diagnostics are available for the following conditions

(see Figs 4 to 7):

• Amplifier in ‘mute’

• Chip temperature greater than 145 °C

• Distortion over 2.0% due to clipping

• Short-circuit protection active.

LIMITING VALUES

In accordance with the Absolute Maximum Rating System (IEC 134).

Note

1. The maximum supply voltage under short circuit conditions is 28 V with an additional resistor in the supply line of

tbf

Ω.

SYMBOL

PARAMETER

CONDITIONS

MIN.

MAX.

UNIT

supply voltage

operating

8

28

V

load dump protected;

see Fig.3

−

45

V

voltage on diagnostic pin

−

18

V

non-repetitive peak output current

−

6A

repetitive peak output current

−

4.5

A

reverse polarity voltage

−

6V

AC and DC short-circuit voltage of output

pins across loads and to ground or supply

pins

no external series

resistor in supply line;

note 1

−

24

V

total power dissipation

−

75

W

junction temperature

−

150

°C

storage temperature

−55

+150

°C

operating ambient temperature

−40

+150

°C