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Philips Semiconductors
2
25 W high efficiency car radio power
amplifier
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
SYMBOL
V
supply voltage
P
V
short-circuit safe voltage
P(sc)
V
reverse polarity voltage
rp
I
repetitive peak output current
ORM
P
total power dissipation
tot
T
storage temperature
stg
T
virtual junction temperature
vj
T
ambient temperature
amb
THERMAL CHARACTERISTICS
SYMBOL
R
thermal resistance from junction to case
th(j-c)
R
thermal resistance from junction to ambient
th(j-a)
Note
1. The value of R
th(c-h)
Heatsink design
There are two parameters that determine the size of the
heatsink. The first is the rating for the virtual junction
temperature and the second is the ambient temperature at
which the amplifier must still deliver its full power in the
BTL mode.
With a conventional BTL amplifier, the maximum power
dissipation with a music-like signal (at each amplifier) will
be approximately two times 6.5 W.
At a virtual junction temperature of 150 C and a maximum
ambient temperature of 65 C, R
R
= 0.2 K/W, the thermal resistance of the heatsink
th(c-h)
150 65
150 65
–
–
should be:
--------------------- - 1.3
--------------------- - 1.3
–
–
2 6.5
2 6.5
Compared to a conventional BTL amplifier, the TDA1563Q
has a higher efficiency. The thermal resistance of the
heatsink should be:
1.7
2000 Feb 09
PARAMETER
PARAMETER
depends on the application (see Fig.3).
= 1.3 K/W and
th(vj-c)
–
–
0.2
0.2
=
=
5 K/W
5 K/W
145 65
–
--------------------- -
–
1.3
–
0.2
=
2 6.5
CONDITIONS
operating
non-operating
load dump; t
CONDITIONS
see note 1
handbook, halfpage
OUT 1
3.6 K/W
0.6 K/W
9 K/W
Fig.3 Thermal equivalent resistance network.
6
Product specification
MIN.
2.5 ms
r
55
40
VALUE
1.3
40
virtual junction
OUT 1
OUT 2
3.6 K/W
3.6 K/W
0.6 K/W
0.1 K/W
case
TDA1563Q
MAX.
UNIT
18
V
30
V
45
V
18
V
6
V
4
A
60
W
+150
C
150
C
C
UNIT
K/W
K/W
OUT 2
3.6 K/W
MGC424
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