Connection Diagrams

20102902

TO-220, Top View

20102903

TO-263, Top View

Pin Description

Pin Name

Description

BIAS

The bias pin is used to provide the low current bias voltage to the chip which operates the internal

circuitry and provides drive voltage for the N-FET.

OUTPUT

The regulated output voltage is connected to this pin.

GND

This is both the power and analog ground for the IC. Note that both pin three and the tab of the

TO-220 and TO-263 packages are at ground potential. Pin three and the tab should be tied together

using the PC board copper trace material and connected to circuit ground.

INPUT

The high current input voltage which is regulated down to the nominal output voltage must be

connected to this pin. Because the bias voltage to operate the chip is provided seperately, the input

voltage can be as low as a few hundered millivolts above the output voltage.

SHUTDOWN

This provides a low power shutdown function which turns the regulated output OFF. Tie to V

this function is not used.

Ordering Information

Order Number

Package Type

Package Drawing

Supplied As

LP38843S-0.8

TO263-5

TS5B

Rail

LP38843SX-0.8

TO263-5

TS5B

Tape and Reel

LP38843T-0.8

TO220-5

T05D

Rail

LP38843S-1.2

TO263-5

TS5B

Rail

LP38843SX-1.2

TO263-5

TS5B

Tape and Reel

LP38843T-1.2

TO220-5

T05D

Rail

LP38843S-1.5

TO263-5

TS5B

Rail

LP38843SX-1.5

TO263-5

TS5B

Tape and Reel

LP38843T-1.5

TO220-5

T05D

Rail

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