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SLUS223C – APRIL 1997 – REVISED JUNE 2007
ERROR AMP CONFIGURATION
Error amp can source or sink up to 0.5 mA.
2.5 V
+
0.5 mA
Z
I
Z
F
V
FB
COMP
2
1
_
UNDER-VOLTAGE LOCKOUT
During under-voltage lock-out, the output drive is biased to sink minor amounts of current. Pin 6 should be
shunted to ground with a bleeder resistor to prevent activating the power switch with extraneous leakage
currents.
V
CC
V
CC
7
ON/OFF Command
to REST of IC
UC1842
UC1844
V
ON
V
OFF
16 V
10 V
UC1843
UC1845
8.4 V
7.6 V
<17 mA
<1 mA
V
CC
V
OFF
V
ON
CURRENT SENSE CIRCUIT
A small RC filter may be required to suppress switch transients.
ERROR
AMP
I
S
1
R
3
R
S
C
GND
5
5
Peak Current (I
S
) is Determined By The Formula
,1.0 V
I
SMAX
RS
COMP
CURRENT
SENSE
2R
R
1V
CURRENT
SENSE
COMPARATOR
5
TI [ TEXAS INSTRUMENTS ]
