
TL/H/11058
L
February 1995
LM612
Dual-Channel Comparator and Reference
General Description
The dual-channel comparator consists of two individual
comparators, having an input voltage range that extends
down to the negative supply voltage V
b
. The common
open-collector output can be driven low by either half of the
LM612. This configuration makes the LM612 ideal for use
as a window comparator. The input stages of the compara-
tor have lateral PNP input transistors which maintain low
input currents for large differential input voltages and swings
above V
a
.
The 1.2V voltage reference, referred to the V
b
terminal, is a
two-terminal shunt-type band-gap similar to the LM185-1.2
series, with voltage accuracy of
g
0.6% available. The refer-
ence features operation over a shunt current range of 17
m
A
to 20 mA, low dynamic impedance, and broad capacitive
load range.
As a member of National’s Super-Block
TM
family, the
LM612 is a space-saving monolithic alternative to a multi-
chip solution, offering a high level of integration without sac-
rificing performance.
Features
COMPARATORS
Y
Low operating current
300
m
A
4V to 36V
Y
Wide supply voltage range
Y
Open-collector outputs
Y
Input common-mode range
V
b
to (V
a
b
1.8V)
Y
Wide differential input voltage
g
36V
REFERENCE
Y
Fixed output voltage
1.24V
Y
Tight initial tolerance available
g
0.6% (25
§
C)
17
m
A to 20 mA
Y
Wide operating current range
Y
Tolerant of load capacitance
Applications
Y
Voltage window comparator
Y
Power supply voltage monitor
Y
Dual-channel fault monitor
Connection Diagram
TL/H/11058–1
Top View
Ordering Information
For information about surface-mount packaging of this device, please contact the Analog Product Marketing group at
National Semiconductor Corporation headquarters.
Tolerances
Reference
Temperature Range
Package
Package
Number
NSC
Military
Industrial
b
55
§
C
s
T
J
s
a
125
§
C
b
40
§
C
s
T
J
a
85
§
C
g
0.6% at 25
§
C,
80 ppm/
§
C Max
LM612AMN
LM612AIN
8-Pin
N08E
Molded DIP
LM612AMJ/883
(Note 13)
8-Pin
J08A
Ceramic DIP
g
2.0% at 25
§
C,
150 ppm/
§
C Max
LM612MN
LM612IN
8-Pin
N08E
Molded DIP
LM612IM
8-Pin Narrow
Surface Mount
M08A
Super-Block
TM
is a trademark of National Semiconductor Corporation.
C
1995 National Semiconductor Corporation
RRD-B30M115/Printed in U. S. A.