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LT138A/LT338A

LM138/LM338

5A Positive Adjustable

Voltage Regulator

s

Guaranteed 1% Initial Tolerance

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Guaranteed 0.3% Load Regulation

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Guaranteed 5A Output Current

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100% Thermal Limit Burn-In

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12A Transient Output Current

The LT

output current over an output voltage range of 1.2V to 32V.

The internal voltage reference is trimmed to less than 1%,

enabling a very tight output voltage. In addition to excel-

lent line and load regulation, with full overload protection,

the LT138A incorporates new current limiting circuitry

allowing large transient load currents to be handled for

short periods. Transient load currents of up to 12A can be

supplied without limiting, eliminating the need for a large

output capacitor.

The LT138A is an improved version of the popular LM138

with improved circuit design and advanced process tech-

niques to provide superior performance and reliability.

The graph below shows the significant improvement in

output voltage tolerance achieved by using the LT138A or

LT338A.

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High Power Linear Regulator

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Battery Chargers

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Power Driver

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Constant-Current Regulator

, LTC and LT are registered trademarks of Linear Technology Corporation.

Parallel Regulators for Higher Current*

LT338A

0.01

Ω**

THIS CIRCUIT WILL NOT WORK WITH LM VERSION DEVICES

CURRENT SHARING RESISTORS DEGRADE REGULATION TO 1%

*

**

ADJ

LT350A

138/338 TA01

121

Ω

1%

5V

8A

ADJ

0.016

Ω**

365

Ω

1%

Output Voltage Error

OUTPUT VOLTAGE (V)

1

0

3

5

7

10

10

100

138A/338A TA02

1

4

6

9

12

11

8

2

2% RESISTORS

2% RESISTORS

1% RESISTORS

1% RESISTORS

LM338

LM338

LT338A

LT338A

DESCRIPTIO

FEATURES

APPLICATIO S

TYPICAL APPLICATIO