AN10436 PHILIPS [NXP Semiconductors], AN10436 Datasheet - Page 25

• Manufacturer Part Number: AN10436
• Description: TDA8932B/33(B) Class-D audio amplifier
• Manufacturer: PHILIPS [NXP Semiconductors]

NXP Semiconductors
AN10436_1
Application note
3.4 Analog audio input
Remark: Do not use an external pull-up resistor at the ENGAGE input.
Remark: For a quick enable of the MUTE mode it is recommended to short circuit the 10 k
series resistor.
The DIAG pin can be used to:
The internal pull-up current is limited (approx. 50 μA) therefore the maximum resistive
load (referenced to CGND) is 47 kΩ. DIAG open pin voltage is 2.8 V (typ).
The absolute maximum sink current of the DIAG pin should be limited to 5 mA (internal
pull-down resistance R
Remark: The DIAG should be left floating when unused.
The input signal is applied to the differential input of the TDA8932B/33(B) by means of
AC-couple capacitors (see
because the inputs (IN1P, IN1N, IN2P and IN2N) are biased at a voltage level of
approximately +2.2 V (with respect to VSS) when operating from an asymmetrical supply.
At symmetrical supply, the inputs are biased at a voltage level of approximately −2.2 V
(with respect to HVPREF). The bias voltage is equal to the INREF voltage (pin 12).
Remark: The input should be grounded close to the audio source (not at the amplifier
side) to avoid a common ground with the power supply ground.
Fig 22. DIAG circuit to disable power stage
Fig 23. Input circuitry
•
•
Read out the status of respectively OPERATING mode or FAULT mode.
Quickly disable the power stage in case of fault conditions at set level.
OPTIONAL CIRCUIT TO DISABLE POWER STAGE
OPERATING
Rev. 01 — 12 December 2007
FAULT
pd
≈ 1 kΩ when set low).
Figure
4.7 k
4.7 k
R2
R3
ERROR
GND
23). AC-couple capacitors are required for DC-blocking
470 nF
470 nF
C5
C7
TDA8932B/33(B) Class-D audio amplifier
C6
330 pF
IN1N 3
IN1P 2
4
7
CGND
DIAG
2.5 V
R i
100 k
010aaa011
100 k
50 A
1 k
AN10436
010aaa010
© NXP B.V. 2007. All rights reserved.
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