Linear Technology announces the LTC3214, a fractional charge pump, white LED driver that delivers up to 500mA of LED current. Its multi-mode architecture automatically switches between 1x, 1.5x or 2x boost modes monitoring the voltage across the LED current source and switching modes only when ILED dropout is detected. This enables the LTC3214 to maximize efficiency (up to 94%) throughout the entire Li-Ion operating range. A 900kHz switching frequency and a low external parts count (two flying capacitors, two programming resistors and two bypass capacitors at VIN and CPO) provide a very tiny footprint and cost-effective solution, ideally suited for video and flash applications in camera phones and other portable lighting applications.

The LTC3214 employs built-in soft-start circuitry which prevents excessive inrush current during start-up. An ultralow dropout current source maintains accurate LED current as the input voltage approaches the LED forward voltage. The LTC3214 is available in a low profile (0.75mm), 3mm x 3mm 10-lead DFN package. The LTC3214EDD is available from stock in a DFN-10 package. Pricing starts at $1.65 each for 1,000-piece quantities.