July 1994
5
Philips Semiconductors
Product specification
6 W hi-fi audio power amplifier
TDA2613
THERMAL RESISTANCE
HEATSINK DESIGN EXAMPLE
With derating of 8 K/W, the value of heatsink thermal resistance is calculated as follows:
given R
L
= 8
Ω
and V
P
= 24 V, the measured maximum dissipation is 4,1 W; then, for a maximum ambient temperature
of 60
°
C, the required thermal resistance of the heatsink is:
Note: The metal tab (heatsink) has the same potential as pin 5 (GND).
From junction to case
R
th j-c
= 8 K/W
Fig.2 Power derating curve.
R
th h-a
150
60
–
4 1
,
----------------------
8
14 K/W
≈
–
=
