Data Sheet

© Semiconductor Components Industries, LLC, 2010 www.onsemi.com
FOD8316 Rev. 2 24
FOD8316 — 2.5 A Output Current, IGBT Drive Optocoupler with Desaturation Detection and Isolated Fault Sensing
Figure 52 shows the operation with a dual or split power
supply. The Vss supply provides the negative gate bias,
and V
DD2
+ V
SS
supplies power to the output IC. The
V
SS
and V
DD2
supplies require three power supply
bypass capacitors. These capacitors provide the low
equivalent series resistant (ESR) paths for the
instantaneous gate charging and discharging currents.
Selecting capacitors with low ESR will optimize the
available output current. C3 is a low ESR 1812 style,
10 µF, multilayer ceramic capacitor. This capacitor is the
primary filter for the Vss and V
DD2
supplies. C1 and C2
are also low ESR capacitors. They provide the primary
gate charge and discharge paths. The Schottky diode,
D1, is connected between V
E
and V
SS
to protect against
a reverse voltage greater than 0.5 V.
Figure 54. Input/Output Relationship
Figure 55. Timing Relationship Among Desatuation Voltage (DESAT), Fault Output (FAULT
) and
Fault Reset Input (RESET)
V
O
V
IN–
V
IN+
Normal
Operation
Fault Condition Reset
RESET
V
O
FAULT
V
DESAT
V
IN–
0 V
5
V
7 V
0 V
V
IN+
Blanking
Time