General Description

The AP3019A is an inductor-based DC/DC converter designed to drive up to eight white LEDs in series for backlight. Only one feedback resistor is needed to control the LED current and obtain required brightness.

A constant frequency 1.2MHz PWM control scheme is employed in this IC, which means tiny external components can be used. Specifically, 1mm tall inductor and 0.22µF output capacitor for a typical application is sufficient. Additionally, the Schottky diode in boost circuit is integrated on this chip. AP3019A also provides a disable pin to ease its use for different systems.

The output over-voltage protection is implemented in AP3019A. When any LED is broken or in other abnormal conditions, the output voltage will be clamped.

The AP3019A is available in standard SOT-23-6 and TSOT-23-6 packages.

Features

• Inherently Uniform LED Current

• High Efficiency up to 84

• No Need for External Schottky Diode

• Output Over-voltage Protection (OVP)

• Fixed 1.2MHz Switching Frequency

• Uses Tiny 1mm Tall Inductor

• Requires Only 0.22µF Output Capacitor

Applications

• Cellular Phones

• Digital Cameras

• LCD modules

• GPS Receivers

• PDAs, Handheld Computers