The KF9907 is a step-up DC/DC converter specifically designed to drive up to 5 series white LEDs with constant current. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminates the need for ballast resistors. The KF9907 switches at 1.4MHz， allowing the use of tiny external components. A low 0.25V feedback voltage minimizes power loss in the current setting resistor for high efficiency. The OVP pin monitors the output voltage and turns off the converter whenever the LEDs are open.

The KF9907 is available in low profile SOT-23-6 package.

      Features

Inherently Matched LED Current

High Efficiency:82%

Drives Up to Five LEDs from 2.2V Supply

17V Over Voltage Protection

Fast 1.4MHz Switching Frequency

Requires only 1μF Output Capacitors

SOT-23-6 Package

       Application

Communication equipment

White LED Backlight Display for PDA

Pocket PC

Handheld Devices

Cellular Phones

White LED display backlighting