Isolation Amplifier with Short
Circuit and Overload Detection
Technical Data
HCPL-788J
Features
• Output Voltage Directly
Compatible with A/D
Converters (0 V to V
REF
)
• Fast (3
µ
s) Short Circuit
Detection with Transient
Fault Rejection
• Absolute Value Signal Out-
put for Overload Detection
• 1
µ
V/
°
C Offset Change vs.
Temperature
• SO-16 Package
• -40
°
C to +85
°
C Operating
Temperature Range
• 25 kV/
µ
s Isolation Transient
Immunity
• Regulatory Approvals
(Pending): UL, CSA, VDE
0884 (891 Vpeak Working
Voltage)
Low Cost Three Phase Current Sensing with Short Circuit and Overload Detection
ISOLATION BOUNDARY
1
2
3
4
5
6
7
8
+5 V
V
IN+
V
IN-
FAULT
ABSVAL
V
OUT
V
REF
16
15
14
13
12
11
10
R
SENSE1
SHORT CIRCUIT FAULT
MICRO
CONTROLLER
HCPL-788J
9
ISOLATION BOUNDARY
1
2
3
4
5
6
7
A/D
CONVERTER
V
IN+
V
IN-
FAULT
ABSVAL
V
OUT
V
REF
16
15
14
13
12
11
10
R
SENSE2
V
REF
M
3 PHASE
MOTOR
8
HCPL-788J
9
ISOLATION BOUNDARY
1
2
3
4
5
6
7
8
3 PHASE ABSOLUTE
VALUE OUTPUT
V
IN+
V
IN-
FAULT
ABSVAL
V
OUT
V
REF
16
15
14
13
12
11
10
R
SENSE3
+
–
+
–
V
TH
OVERLOAD
FAULT
HCPL-788J
9
Hewlett-Packard’s Isolation Amplifier with Short Circuit and Overload Detection makes
motor phase
current sensing compact, affordable and easy-to-implement
while satisfying worldwide safety and
regulatory requirements.
CAUTION:
It is advised that normal static precautions be taken in handling and assembly of this component to prevent damage and/
or degradation which may be induced by ESD.