HT7938

High Current and Performance White LED Driver

Block Diagram

Rev 1.10

1

March 19, 2010

Features

Applications

General Description

HT7938 is high efficiency boost converter with constant

current output to provide backlight in handheld devices.

Series connection of LEDs provides constant identical

LED currents resulting in uniform brightness. The con-

tinuous LED current is set with FB pin regulated voltage

that pin to ground. The built-in open load protection pre-

vents the damage resulting from an open circuit condi-

tion. Low 200mV feedback voltage minimizes power

loss in the current setting resistor for better efficiency.

HT7938 switches at rates up to 1.2MHz to allow the use

of extremely small inductor and filter capacitor.