ST1938

DC-DC Step-Up Converter for White LED Driver

STANSON TECHNOLOGY

120 Bentley Square, Mountain View, Ca 94040 USA

www.stansontech.com

ST1938 2008. V1

DESCRIPTION

The ST1938 is a step-up DC/DC converter for white LED driver with over voltage protection.

The device can driver one to four LEDs in series from a single cell Lithium Ion battery.

Internal functions include current limiting; thermal shutdown; OVP and soft-start to prevent

damage operate status. The ST1938 operates at 0.8MHz and from low input voltages as low as

1.5V; apply to Lithium-Ion powered systems. A low 95mV reference voltage minimizes power

loss in the current setting resistor for better efficiency.

The ST1938 is available in small package SOT-23-6L

PIN CONFIGURATION

SOT23-6L

PART MARKING

APPLICATIONS

Battery Power Equipment

Notebook Computers

PDA

Cellular Phone

FEATURES

Current Source with Over Voltage

Protection

Fast 0.8MHz Switching Frequency

High Efficiency up to 87%

Drives up to Four LEDs From 3.2V

Supply

Drives up to Six LEDs From a 5V Supply

Low Quiescent Current

Disconnects LEDs in Shutdown Mode

Internal Over Temperature and Current

Limiting Shutdown Function

Internal Soft-Start Circuit

36V Rugged Bipolar Switch

Available in a Small SOT-23-6L Package