Philips Semiconductors
Product specification
2 × 40 W/2 Ω stereo BTL car radio power
amplifier with diagnostic facility
TDA8563AQ
During this short-circuit condition, pin 12 is low for 20 ms
SHORT-CIRCUIT PROTECTION
and high for 50 µs (see Fig.4).
When a short-circuit occurs at one or more outputs to
ground or to the supply voltage, the output stages are
switched off until the short-circuit is removed and the
device is switched on again, with a delay of approximately
20 ms, after removal of the short-circuit. During this
short-circuit condition, pin 12 is continuously low.
The power dissipation in any short-circuit condition is
very low.
TEMPERATURE DETECTION
When the virtual junction temperature Tvj reaches 150 °C,
When a short-circuit across the load of one or both
channels occurs the output stages are switched off during
approximately 20 ms. After that time it is checked during
approximately 50 µs to see whether the short-circuit is still
present. Due to this duty cycle of 50 µs/20 ms the average
current consumption during this short-circuit condition is
very low (approximately 40 mA).
pin 12 will become continuously low.
OPEN COLLECTOR OUTPUT
Pin 12 is an open collector output, which allows pin 12 of
more devices being tied together.
current
handbook, full pagewidth
in
MGA722
output
stage
t
short-circuit over the load
V
12
20 ms
V
P
t
µ
50
s
Fig.4 Short-circuit waveform.
1997 Feb 20
5
NXP [ NXP ]
