LM3557 Datasheet, PDF (2/11 Pages) National Semiconductor (TI) – Step-Up Converter for White LED Applications

Connection Diagram
Top View
20131602
8-Lead Thin Leadless Leadframe Package
See NS Package Number SDA08A
Ordering Information
Order Number
LM3557SD-2
LM3557SDX-2
Package
Marking
L147B
L147B
Supplied As
1k Units, Tape and Reel
4.5k Units, Tape and Reel
Pin Description
Pin #
1
2
3
4
5
6
7
8
DAP
Name
Sw1
V_IN
NC
En
Ovp
Fb
Sw2
Gnd
DAP
Description
Drain Connection of the Internal Power Field Effect Transistor (FET) Switch (Figure 2: N1)
Input Voltage Connection
No Connection
Device Enable Connection
Over-Voltage Protection Input Connection
Feedback Voltage Connection
Drain Connection of an Internal Field Effect Transistor (FET) Switch (Figure 2: N2)
Ground Connection
Die Attach Pad (DAP), must be soldered to the printed circuit board’s ground plane for enhanced thermal
dissipation
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2