TLH7751

September 1992

LM112LM212LM312 Operational Amplifiers

General Description

The LM112 series are micropower operational amplifiers

with very low offset-voltage and input-current errorsat

least a factor of ten better than FET amplifiers over a

b

series that also use supergain transistors they differ in that

they include internal frequency compensation and have pro-

visions for offset adjustment with a single potentiometer

g

20V drawing a quiescent current of only 300 mA Per-

formance is not appreciably affected over this range of volt-

ages so operation from unregulated power sources is easily

accomplished They can also be run from a single supply

like the 5V used for digital circuits

The LM112 series are the first IC amplifiers to improve reli-

ability by including overvoltage protection for the MOS com-

pensation capacitor Without this feature IC’s have been

known to suffer catastrophic failure caused by short-dura-

tion overvoltage spikes on the supplies Unlike other inter-

nally-compensated IC amplifiers it is possible to overcom-

pensate with an external capacitor to increase stability mar-

gin

The LM212 is identical to the LM112 except that the LM212

range

Features

Y

Maximum input bias current of 3 nA over temperature

Y

Offset current less than 400 pA over temperature

Y

Low noise

Y

Guaranteed drift specifications

Connection Diagram

Metal Can Package

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Top View

Order Number LM112H LM212H LM312H or LM112H883

See NS Package Number H08C

Auxiliary Circuits

Offset Balancing

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Overcompensation for Greater Stability Margin

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C1995 National Semiconductor Corporation

RRD-B30M115Printed in U S A