Power integrations InnoSwitch3 Application Note page 32

Application Note AN-72
Diode Across Current Sense R
IS
A diode (Schottky or ultrafast) positioned
across the current sense resistor (R ) acts
D V
IS
as a bypass for very high surge of current InnoSwitch3
and voltage during short-circuit which
VOUT
Primary FET
Diode
could potentially damage R . This is more
and Controller
R
IS IS
likely for designs with high output voltage
S IS
BPP Secondary
and high output filter capacitance.
Control IC
PI-8469-101017
Capacitor Across Current Sense R
D V
IS
Putting a capacitor (10 - 100 nF) across IS
InnoSwitch3
and GND pins when R is placed some-
VOUT
Primary FET
IS
C
what away from the IC will reduce pulse
and Controller
R GS
IS
grouping (bunching) in CC operation.
S IS
BPP Secondary
Control IC
PI-8544-111017
Figure 25 (cont.). Circuit Ideas to Enhance Design.
32
Rev. A 10/18
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