The KF9909A is a step-up DC/DC converter specifically designed for driving white LEDs with a constant curent. The intermal MOSFET can support up to 10 White LEDs for backlighting and OLED power application, and the intemal soft start function can reduce the inrush current. The KF9909A uses current mode, fixed frequency of approximately 1.0MHz architecture to regulate the LED current through an extermal current sense resistor. The low feedback voltage of 300mV can minimize power dissipation.

Other features include current limit protection, thermal shutdown protection, under-voltage lockout (UVLO), and over-voltage function.

The KF9909A is available in space saving SOT-23-6L and DFN-8L (2mm x 2mm) packages.

     Features

VIN Operating Range: 2.5V to 5.5V

Intermal Power N-MOSFET Switch

Wide Range for PWM Dimming (100Hz to200kHz)

1.0MHz Switch Frequency

300mV Feedback Voltage

1.2A SW Current Limit

Minimize the External Component Counts

Internal Compensation

Over Voltage Protection

         Application

Cellular Phones and Digital Cameras

PDAs and Smart Phones and MP3 and OLED

Portable Instruments

High-light LED Flash