July 1994

5

Philips Semiconductors

Product specification

2 x 12 W hi-fi audio power amplifier

TDA1521

TDA1521Q

Fig.2 Power derating curve.

THERMAL RESISTANCE

HEATSINK DESIGN EXAMPLE

With derating of 2,5 K/W, the value of heatsink thermal resistance is calculated as follows:

of 65

°C, the required thermal resistance of the heatsink is

Note: The internal metal block (heatsink) has the same potential as pin 5 (

From junction to case

R

th h

a

–

150

65

–

14 6

,

----------------------

25

33 K W

⁄

,

=

,

–

=