MB3882 Datasheet, PDF (21/30 Pages) Fujitsu Component Limited. – 2-channel DC/DC Converter IC with Synchronous Rectifier

MB3882
s OVERVOLTAGE PROTECTION CIRCUIT VOTAGE SETTING
Overvoltage conditions in the DC/DC converter output voltage can be detected by connecting external resistance
from the DC/DC converter output voltage to the +INC1 terminal (pin 7) and +INC2 terminal (pin 18) on the
respective overvoltage protection comparator circuits (OVP comp. 1, 2) .
When the output voltage of the DC/DC converter rises above the detection voltage, the overvoltage protection
comparator (OVP Comp. 1, 2) output goes to “H” level, setting a latch and shutting off the corresponding channel.
Each of the overvoltage protection circuit latches operates independently.
Detection voltage
VOVP (V) =: 1.47 × (R3 + R4) /R4
Once the protection circuit has been activated, it can be reset by lowering the VCC voltage below the reset
voltage (1.7 V min.) .
VO
R3
(+INC2) 18
7
+INC1
R4
VCC
OVP
+ ^Comp.
−
RQ
S
1.47 V
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