Out2; Short-Circuit Diagnostic (Pin Diag); Temperature Pre-Warning (Pin Diag); Open-Collector Diagnostic Outputs - Philips TDA8566 Product Data Sheet

NXP Semiconductors

7.3 Short-circuit diagnostic (pin DIAG)

7.4 Temperature pre-warning (pin DIAG)

7.5 Open-collector diagnostic outputs

TDA8566_6
Product data sheet
Fig 5. Clip detection waveforms
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 the removal of the short-circuit).
During this short-circuit condition, pin DIAG is continuously LOW.
When a short-circuit occurs across the load of one or both channels, the output stages are
switched off for approximately 20 ms. After that time the load condition is checked during
approximately 50 s to see whether the short-circuit is still present. Due to this duty cycle
of 50 s/20 ms the average current consumption during the short-circuit condition is very
low (approximately 40 mA). During this condition, pin DIAG is LOW for 20 ms and HIGH
for 50 s; see Figure 6. The power dissipation in any short-circuit condition is very low.
current
in
output
stage
short-circuit over the load
V
DIAG
(V)
Fig 6. Short-circuit diagnostic timing diagram
When the virtual junction temperature (T
continuously LOW.
Pins DIAG and CLIP are open-collector outputs, therefore more devices can be tied
together. Pins DIAG and CLIP can also be tied together. An external pull-up resistor is
required.
2 40 W/2
V
O
(V)
0
V
CLIP
(V)
0
50 s
) reaches 145 C, pin DIAG will become
vj
Rev. 06 — 15 October 2007
TDA8566
stereo BTL car radio power amplifier
t (s)
mgu357
20 ms
© NXP B.V. 2007. All rights reserved.
t (s)
t (s)
mgu360
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