TDF8591TH NXP Semiconductors, TDF8591TH Datasheet - Page 9

• Manufacturer Part Number: TDF8591TH
• Description: The TDF8591TH is a high-efficiency class-D audio power amplifier with low powerdissipation for application in car audio systems
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDF8591TH_1
Product data sheet
6.5 Diagnostic output
6.6 Differential inputs
[3]
[4]
Pin DIAG is pulled LOW when the OCP is triggered. With a continuous short-circuited load
a switching pattern in the voltage on pin DIAG is observed (see
LOW on pin DIAG indicates a short-circuit to the supply lines whereas a short-circuited
load causes a switching DIAG pin (see
The pin DIAG reference voltage is V
pull-up. An example of a circuit to read out and level shift the diagnostic data is given in
Figure
microprocessor that reads out the DIAG data.
For a high Common Mode Rejection Ratio (CMRR) and a maximum of flexibility in the
application, the audio inputs are fully differential. By connecting the inputs anti-parallel the
phase of one of the channels can be inverted, so that a load can be connected between
the two output filters. In this case the system operates as a mono BTL amplifier.
The input configuration for a mono BTL application is illustrated in
In the stereo SE configuration it is also recommended to connect the two differential
inputs in anti-phase. This has advantages for the current handling of the supply voltage at
low signal frequencies (supply pumping).
Fig 7. DIAG readout circuit with level shift
Only complete shut down of amplifier in case of a short-circuit. In all other cases current limiting resulting in
clipping output signal.
Fault condition detected during (every) transition between standby-to-mute and during restart after
activation of OCP (short-circuit to one of the supply lines).
7. V5V represents a logic supply that is used in the application by the
Rev. 01 — 5 March 2008
V
DIAG
V
2
DDA
SSA
100 W SE (4 ) or 1
100 k
SSA
. Pin DIAG should not be connected to an external
Section
5.6 V
M1
6.4.3).
100 k
27 k
SGND
V5V
310 W BTL (4 ) class-D amplifier
M2
10 k
001aad840
DIAG
out
Figure
TDF8591TH
Figure
6). A permanent
© NXP B.V. 2008. All rights reserved.
8.
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