Description
The Supertex HV9903 is a fixed frequency DC-DC boost converter designed for driving Light Emitting Diodes (LEDs) with constant current where the light intensity is proportional to the current through them. The input supply voltage range into the device (VDD) is 2.6 to 4.6V. Operation of the driver at lower voltages is possible as long as a 2.6–4.6V low current supply is available for the HV9903. The device uses a single inductor and a minimum number of passive components. The device can be enabled/disabled via the SHDN pin.

Features
❑ Power efficiency of up to 85%
❑ Drives up to 6 White LEDs
❑ 2.6V to 4.6V Supply power stage can operate at 1.8V (see page 8)
❑ Built-in Soft Start
❑ DC and PWM Dimming Control
❑ Built-in Open LED protection
❑ Open LED indicator (via RSET)
❑ 1.2MHz Fixed Switching Frequency
❑ 500nA max leakage current when disabled
❑ No leakage current path through LEDs when disabled
❑ Resistor-programmable LED Current
❑ Small 6-lead MLP (3mm x 3mm) package (similar to 6-pin SOT-23)

Applications
❑ Color LCD Backlighting
❑ Cell phones, smart phones
❑ PDAs, pocket PCs
❑ Organizers
❑ Digital Cameras
❑ MP3 Players