LT138A/LT338A

LM138/LM338

1

138afd

For more information www.linear.com/LT138A

Typical applicaTion

FeaTures

applicaTions

DescripTion

5A Positive Adjustable

Voltage Regulator

The LT®138A series of adjustable regulators provide 5A

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 excellent line and load regulation, with full overload

protection, the LT138A incorporates new current limit-

ing 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.

Parallel Regulators for Higher Current*

n

Guaranteed 1% Initial Tolerance

n

Guaranteed 0.3% Load Regulation

n

Guaranteed 5A Output Current

n

100% Thermal Limit Burn-In

n

12A Transient Output Current

n

High Power Linear Regulator

n

Battery Chargers

n

Power Driver

n

Constant-Current Regulator

Output Voltage Error

LT338A

0.01Ω∗∗

THIS CIRCUIT WILL NOT WORK WITH LM VERSION DEVICES

CURRENT SHARING RESISTORS DEGRADE REGULATION TO 1%

*

**

ADJ

LT350A

138/338 TA01

121Ω

1%

5V

8A

ADJ

0.016Ω**

365Ω

1%

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

L

, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear

Technology Corporation. All other trademarks are the property of their respective owners.

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FOR INFORMATION PURPOSES ONLY

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