Connection Diagram

Top View

20131602

8-Lead Thin Leadless Leadframe Package

See NS Package Number SDA08A

Ordering Information

Order Number

Package

Marking

Supplied As

LM3557SD-2

L147B

1k Units, Tape and Reel

LM3557SDX-2

L147B

4.5k Units, Tape and Reel

Pin Description

Pin #

Name

Description

1

Sw1

Drain Connection of the Internal Power Field Effect Transistor (FET) Switch (Figure 2: N1)

2V

IN

Input Voltage Connection

3

NC

No Connection

4

En

Device Enable Connection

5

Ovp

Over-Voltage Protection Input Connection

6

Fb

Feedback Voltage Connection

7

Sw2

Drain Connection of an Internal Field Effect Transistor (FET) Switch (Figure 2: N2)

8

Gnd

Ground Connection

DAP

DAP

Die Attach Pad (DAP), must be soldered to the printed circuit board’s ground plane for enhanced thermal

dissipation

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2