SM8120A

NIPPON PRECISION CIRCUITS INC.—1

White LED Driver IC

OVERVIEW

The SM8120A is a high efficiency step-up DC/DC converter. Due to high voltage CMOS process realizing

24V output supply as maximum value, white LED of 2–4 lights connected in series can be lighted. By connect-

ing in series, current variation among LED is eliminated. Current value sent to white LED can be set by exter-

nal resistors. In addition, brightness can also be adjusted by control to FB pin or CE pin.

FEATURES

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Boost-up control using PFM

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White LED of 2-4 lights (connected in series)

lighted

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Output current value can be set by external resis-

tors (51

Ω: 9.8mA, 33Ω: 15.2mA, 24Ω: 20.8mA)

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Brightness adjustable by control to FB pin or CE

pin

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Current variation among LED decreased by high

precision

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High efficient drive by step-up model

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Supply voltage range: 2.4 to 5.5V

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Maximum output voltage: 24V

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Quiescent current: 80

µA (typ)

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Standby current: 1.0

µA (max)

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Maximum switching frequency: 500kHz (typ)

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Output current detection accuracy:

± 2%

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Small package: SOT23-5

APPLICATIONS

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Cellular phone

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Pager

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Digital still camera

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Handy terminal

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PDAs

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Portable games

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White LED drive

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LCD bias supply

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Flash memory supply

ORDERING INFORMATION

PINOUT

(Top view)

PACKAGE DIMENSIONS

(Unit: mm)

Device

Package

SM8120AH

SOT23-5

VDD

VSS

SW

1

2

3

CE

FB

5

4

1.9 ± 0.2

2.9 ± 0.2

0.15 − 0.05

+ 0.1

0.12 M

0.1

0.95

0.4 ± 0.1