AN10436 PHILIPS [NXP Semiconductors], AN10436 Datasheet - Page 13

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

NXP Semiconductors
Table 2.
AN10436_1
Application note
Feature
TF
Cycle-by-cycle
current limiting
WP
UVP
(V
OVP
(V
UBP
DDA
DDA
[1]
[3]
− V
− V
SSA
SSA
Overview of all the limiting and protection features inside the TDA8932B/33(B)
)
)
2.6 Limiting and protection features
-
TDA8932B
TDA8933(B) 2.0 A
low level
high level
-
-
low level
high level
The TDA8932B/33(B) device utilizes two advanced limiting features, the thermal foldback
and the cycle-by-cycle current limiting, to avoid audio holes (interruptions) during normal
operation.
In addition to these limiting features the device has several protection features that make
the TDA8932B/33(B) very robust during a fault condition. The following protections are
incorporated:
When one of the above protections is triggered, the device will enter the FAULT mode and
the power stage is disabled immediately (floating). Furthermore, an internal timer of about
100 ms is started and the DIAG (pin 4), referenced to CGND, is set low for the first 50 ms
of the timer to indicate this protection status (FAULT mode). In addition the internal pull-up
current of the ENGAGE pin is disabled in the FAULT mode, so the external capacitor will
be discharged by means of the internal pull-down resistor (100 kΩ). After about 100 ms
the device will restart (self-recovering), but only when the fault condition has been
resolved.
A microcontroller can use the diagnostic signal (DIAG) to, e.g., shut down either the
amplifier or the power supply.
•
•
•
•
•
•
Window Protection (WP)
UnderVoltage Protections (UVP)
OverVoltage Protection (OVP)
UnBalance Protection (UBP)
OverCurrent Protection (OCP)
OverTemperature Protection (OTP)
14.4
-
Trigger level
Min
140 °C
4.0 A
7.6
8.0 V
36 V
-
[1]
[1]
Typ
-
5.0 A
2.3 A
-
-
9.5 V
38.5 V
17.6 V
29.3 V
Rev. 01 — 12 December 2007
[3]
[3]
Max
150 °C
-
-
-
-
10 V
40 V
-
-
DIAG
output
high
high
low
low
low
low
[2]
[2]
[2]
[2]
TDA8932B/33(B) Class-D audio amplifier
Remark
Unique thermal limiting to avoid audio holes
when the junction temperature exceeds
140 °C during normal operation. (See
Section
Unique current limiting to avoid audio holes
when the current exceeds the trigger level
during normal operation. (See
Power stage stays floating and entering
FAULT mode. (See
Power stage becomes floating entering
FAULT mode. (See
Power stage becomes floating entering
FAULT mode. (See
Power stage becomes floating entering
FAULT mode. (See
2.6.1)
Section
Section
Section
Section
AN10436
© NXP B.V. 2007. All rights reserved.
2.6.3)
2.6.4)
2.6.5)
2.6.6)
Section
2.6.2)
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