July 1994

4

Philips Semiconductors

Product specification

2 x 12 W hi-fi audio power amplifier

TDA1521

TDA1521Q

FUNCTIONAL DESCRIPTION

This hi-fi stereo power amplifier is designed for mains fed applications. The circuit is designed for both symmetrical and

asymmetrical power supply systems. An output power of 2

× 12 watts (THD = 0,5%) can be delivered into an 8 Ω load

with a symmetrical power supply of

± 16 V.

The gain is fixed internally at 30 dB. Internal gain fixing gives low gain spread and very good balance between the

amplifiers (0,2 dB).

A special feature of this device is a mute circuit which suppresses unwanted input signals during switching on and off.

Referring to Fig.13, the 100

µF capacitor creates a time delay when the voltage at pin 3 is lower than an internally fixed

reference voltage. During the delay the amplifiers remain in their DC operating mode but are isolated from the

non-inverting inputs on pins 1 and 9.

Two thermal protection circuits are provided, one monitors the average junction temperature and the other the

instantaneous temperature of the power transistors. Both protection circuits activate at 150

°C allowing safe operation to

a maximum junction temperature of 150

°C without added distortion.

RATINGS

Limiting values in accordance with the Absolute Maximum System (IEC 134)

Note

PARAMETER

CONDITIONS

SYMBOL

MIN.

MAX.

UNIT

Supply voltage

pin 7

−

+21

V

pin 5

−V

−−21

V

Non-repetitive peak

output current

pins 4 and 6

−

4A

Total power dissipation

see Fig.2

Storage temperature range

−55

+150

°C

Junction temperature

−

150

°C

Short-circuit time:

see note

outputs short-circuited

to ground

symmetrical

(full signal drive)

power supply

−

1

hour

asymmetrical

power supply;

(unloaded);

−

1

hour