MC3423
Overvoltage Crowbar
Sensing Circuit
This overvoltage protection circuit (OVP) protects sensitive
electronic circuitry from overvoltage transients or regulator failures
when used in conjunction with an external “crowbar” SCR. The
device senses the overvoltage condition and quickly “crowbars” or
short circuits the supply, forcing the supply into current limiting or
opening the fuse or circuit breaker.
The protection voltage threshold is adjustable and the MC3423 can
be programmed for minimum duration of overvoltage condition
before tripping, thus supplying noise immunity.
The MC3423 is essentially a “two terminal” system, therefore it
can be used with either positive or negative supplies.
http://onsemi.com
MARKING
DIAGRAMS
8
PDIP−8
P1 SUFFIX
PLASTIC PACKAGE
CASE 626
1
MC3423P1
AWL
YYWW
Features
• Pb−Free Package is Available
MC3423P1 = Device Code
A
= Assembly Location
WL
= Wafer Lot
YY
= Year
WW
= Work Week
MAXIMUM RATINGS
Rating
Symbol
Sense Voltage (2)
Unit
40
Vdc
VSense1
Sense Voltage (1)
Value
VCC−VEE
Differential Power Supply Voltage
6.5
Vdc
VSense2
6.5
Vact
7.0
Vdc
Output Current
IO
300
Operating Ambient Temperature Range
TA
0 to +70
TJ
125
°C
Tstg
−65 to +150
°C
3423
ALYW
°C
Operating Junction Temperature
SOIC−8
D SUFFIX
PLASTIC PACKAGE
CASE 751
mA
Remote Activation Input Voltage
Storage Temperature Range
Vdc
8
8
Maximum ratings are those values beyond which device damage can occur.
Maximum ratings applied to the device are individual stress limit values (not
normal operating conditions) and are not valid simultaneously. If these limits
are exceeded, device functional operation is not implied, damage may occur
and reliability may be affected.
1
3423
A
L
Y
W
1
= Device Code
= Assembly Location
= Wafer Lot
= Year
= Work Week
PIN CONNECTIONS
Current
Limited
DC
Power
Supply
Cout
Drive
Output
7
VEE
Sense 2 3
O. V. P.
MC3423
8
6
Indicator
Output
Current
4
Source
+
VCC 1
Sense 1 2
Vout
Vin
5
Remote
Activation
(Top View)
Figure 1. Simplified Application
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 7 of this data sheet.
© Semiconductor Components Industries, LLC, 2005
March, 2005 − Rev. 5
1
Publication Order Number:
MC3423/D