8

UC17131/2/3

UC27131/2/3

UC37131/2/3

C

CDEL

13

12

11

VREF

IN

6

10

3

7

LS

CSH

2

GND

6V

PRE-REGULATOR

INPUT

COMPARATOR

1/2

VREF

HYST

9

LED

TURN-ON/OFF

AND SHORT

CIRCUIT

PROTECTION

CDEL

4

HS

5

Q

OUT

72V

–L

CSL

+L

OUT

C

CC

I

GND

R

CSL

LOAD

POWER

SUPPLY

C

REF

R

HYST

VREF

GND

VCC

I

CC

Figure 2b. Low side application.

APPLICATION INFORMATION (cont.)

UDG-98028

OUTPUT

DRIVER

DISABLED

ENABLED

V

CDEL

VCC

V

FAULT_H =4.9V

V

FAULT_H

t

INT

ENABLED

INDETERMINATE

STATE

t

D(ON)

t

t

t

V

CDEL_MAX =5.8V

Figure 3a. Power interrupt ignore operation, high side configuration, VIN = 5VDC.

UDG-98029