2009/06/15

Ver.5

Page 1

SP1937

DC-DC Step-Up Converter for White LED

DESCRIPTION

APPLICATIONS

The SP1937 is a step-up DC/DC converter for white

LED driver with constant current. The device can driver

one to four LEDs in series from a single cell Lithium

Ion battery. Internal functions include current limiting;

thermal shutdown and soft-start to prevent damage

operate status. The SP1937 DC/DC converter operates

at 1.2MHz and low output capacitor as small as 0.22uF;

apply to Lithium-Ion powered systems. A low 95mV

(Typ) reference voltage minimizes power loss in the

current setting resistor for better efficiency.

Battery Power Equipment

Notebook Computers

PDA

Cellular Phone

Digital Cameras

MP3 Players

GPS Receivers

FEATURES

PIN CONFIGURATION

SOT-23-5L

SOT-353 ( SC-70-5L )

PART MARKING

SOT-23-5L

SOT-353 ( SC-70-5L )

Fast 1.2MHz Switching Frequency

High Efficiency up to 85%

Drives up to Four LEDs From 3.2V Supply

Low Quiescent Current

Disconnects LEDs in Shutdown Mode

Internal Over Temperature and Current Limiting

Shutdown Function

36V Rugged Bipolar Switch

Small Package SOT-23-5L & SOT-353