LM79MXX Series

3-Terminal Negative Regulators

General Description

The LM79MXX series of 3-terminal regulators is available

with fixed output voltages of −5V, −12V, and −15V. These

devices need only one external component — a compensa-

tion capacitor at the output. The LM79MXX series is pack-

aged in the TO-220 power package, and is capable of sup-

plying 0.5A of output current.

These regulators employ internal current limiting, safe area

protection, and thermal shutdown for protection against vir-

tually all overload conditions.

Low ground pin current of the LM79MXX series allows out-

put voltage to be easily boosted above the preset value with

a resistor divider. The low quiescent current of these devices

with a specified maximum change with line and load ensures

good regulation in the voltage boosted mode.

For output voltage other than −5V, −12V, and −15V the

LM137 series provides an output voltage range from −1.2V

to −57V.

Features

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Thermal, short circuit and safe area protection

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High ripple rejection

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0.5A output current

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4% tolerance on preset output voltage

Connection Diagram

TO-220 Plastic Package (T)

DS010483-7

Front View

Order Number LM79M05CT, LM79M12CT or LM79M15CT

See NS Package Number T03B

September 2001

© 2001 National Semiconductor Corporation

DS010483

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