LM111/LM211/LM311
Voltage Comparator
1.0 General Description
The LM111, LM211 and LM311 are voltage comparators that
have input currents nearly a thousand times lower than
devices like the LM106 or LM710. They are also designed to
operate over a wider range of supply voltages: from standard
± 15V op amp supplies down to the single 5V supply used for
IC logic. Their output is compatible with RTL, DTL and TTL
as well as MOS circuits. Further, they can drive lamps or
relays, switching voltages up to 50V at currents as high as
50 mA.
Both the inputs and the outputs of the LM111, LM211 or the
LM311 can be isolated from system ground, and the output
can drive loads referred to ground, the positive supply or the
negative supply. Offset balancing and strobe capability are
provided and outputs can be wire OR’ed. Although slower
than the LM106 and LM710 (200 ns response time vs 40 ns)
3.0 Typical Applications
the devices are also much less prone to spurious oscillations. The LM111 has the same pin configuration as the
LM106 and LM710.
The LM211 is identical to the LM111, except that its performance is specified over a −25˚C to +85˚C temperature range
instead of −55˚C to +125˚C. The LM311 has a temperature
range of 0˚C to +70˚C.
2.0 Features
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Operates from single 5V supply
Input current: 150 nA max. over temperature
Offset current: 20 nA max. over temperature
Differential input voltage range: ± 30V
Power consumption: 135 mW at ± 15V
(Note 3)
Offset Balancing
Strobing
DS005704-36
DS005704-37
Note: Do Not Ground Strobe Pin. Output is turned off when current is
pulled from Strobe Pin.
Increasing Input Stage Current (Note 1)
Detector for Magnetic Transducer
DS005704-38
Note 1: Increases typical common mode slew from 7.0V/µs to 18V/µs.
DS005704-39
© 2001 National Semiconductor Corporation
DS005704
www.national.com
LM111/LM211/LM311 Voltage Comparator
January 2001
