FAN8800 (KA3162)

7

Application Information

1) Two modes in Fault-Out Duration.

- OCP mode

-SCP mode

1) When SCP (Short Circuit Protection) is operated, Q3 turns on and Q2 turns on.

2) In the upper condition, Q2 flows the constant current of 35mA.

3) The capacitance of IGBT as the load is discharging by 35mA, that is Slow Turn-off.

4) Slow Turn-off time is

T

DUR

C

1.4V

–

()

×

⁄

=

2.7nF 55

µA5V 1.4V

–

()

×

⁄

=

176

µs

=

5

L

O

A

D

Vlink

Q3

Q2

Q1

Low

Low

Internal Circuit

T

SLOW

C

V5max

V5min

–

()

×

⁄

=

4.7nF 35mA

15V

1V

–

()

×

⁄

=

1.9

µs

=