Original Creation Date: 06/27/95

Last Update Date: 09/18/95

Last Major Revision Date: 06/27/95

MDLM117-H REV 0A0

MICROCIRCUIT DATA SHEET

POSITIVE THREE TERMINAL ADJUSTABLE VOLTAGE REGULATOR

General Description

The LM117 adjustable 3-terminal positive voltage regulator is capable of supplying in

excess of 0.5A over a 1.2V to 37V output range. It is exceptionally easy to use and

requires only two external resistors to set the output voltage. Further, both line and

load regulation are better than standard fixed regulators.

In addition to higher performance than fixed regulators, the LM117 offers full overload

protection available only in IC's. Included on the chip are current limit, thermal

overload protection and safe area protection. All overload protection circuitry remains

fully functional even if the adjustment terminal is disconnected.

Normally, no capacitors are needed unless the device is situated more than 6 inches from

the input filter capacitors in which case an input bypass is needed. An optional output

capacitor can be added to improve transient response. The adjustment terminal can be

bypassed to achieve very high ripple rejection ratios which are difficult to achieve with

standard 3-terminal regulators.

Besides replacing fixed regulators, the LM117 is useful in a wide variety of other

applications. Since the regulator is "Floating" and sees only the input-to-output

differential voltage, supplies of several hundred volts can be regulated as long as the

maximum input to output differential is not exceeded, (i.e., avoid short-circuiting the

output).

Also, it makes an especially simple adjustable switching regulator, a programmable output

regulator, or by connecting a fixed resistor between the adjustment pin and output, the

LM117 can be used as a precision current regulator. Supplies with electronic shutdown can

be achieved by clamping the adjustment terminal to ground which programs the output to

1.2V where most loads draw little current.

NS Part Numbers

LM117H-SMD

Industry Part Number

LM117H

Prime Die

LM117H

Controlling Document

DESC.# 7703401XA

Processing

MIL-STD-883, Method 5004

Quality Conformance Inspection

MIL-STD-883, Method 5005

Subgrp Description

Temp ( C)

o

1

Static tests at

+25

2

Static tests at

+125

3

Static tests at

-55

4

Dynamic tests at

+25

5

Dynamic tests at

+125

6

Dynamic tests at

-55

7

Functional tests at

+25

8A

Functional tests at

+125

8B

Functional tests at

-55

9

Switching tests at

+25

10

Switching tests at

+125

11

Switching tests at

-55

1