IRAUDAMP5 Datasheet, PDF (13/49 Pages) International Rectifier – 120W x 2 Channel Class D Audio Power Amplifier Using the IRS2092S and IRF6645

Over-Current Protection (OCP)
In the IRAUDAMP5, the IRS2092S gate driver accomplishes OCP internally, a feature discussed
in greater detail in the “Protection” section.
Offset Null (DC Offset)
The IRAUDAMP5 is designed such that no output-offset nullification is required, thanks to
closed loop operation. DC offsets are tested to be less than ±20mV.
Protection
The IRAUDAMP5 has a number of protection circuits to safeguard the system and speaker as
shown in the figure 13 below, which fall into one of two categories – internal faults and external
faults, distinguished by the manner in which a fault condition is treated. Internal faults are only
relevant to the particular channel, while external faults affect the whole board. For internal faults,
only the offending channel is stopped. The channel will hiccup until the fault is cleared. For
external faults, the whole board is stopped using the shutdown sequencing described earlier. In
this case, the system will also hiccup until the fault is cleared, at which time it will restart
according to the startup sequencing described earlier.
.
+
1.2V
CSH
VB
HO
R43
D1
BAV19
R32
10R
+B
Q3
IRF6645
LP Filter
. CSD _CSD
OCREF
VS
.
VCC
LO
R30
10R
Q4
IRF6645
To next channel
5.1V
OCREF
R19
R18
OCSET
Trip
COM
Green
Yellow
LEDs
RESET
UVP
-B
OVP
OTP
DCP
Functional Block Diagram of Protection Circuit Implementation
Fig 13
www.irf.com
IRAUDAMP5 REV 3.0
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