ADI’s LED Driver Brightens Camera Phone Flash

Employing a unique power-management technique that maintains picture quality when a battery strains under multiple phone functions operating simultaneously, the ADP1653 dual, white LED driver promises brighter camera flashes than single or low-efficiency white LED drivers. Power efficiency peaks at 92% and is typically greater than 80% over the full voltage range of a lithium-ion battery. Unlike standard step-up dc/dc converters, the device features a logic-input pin that reduces the white LED current to its lowest operating level in less than 50 ms when the phone activates the power amp. It drives two series-connected, high-brightness white LEDs with currents up to 500 mA as well as a separate indicator LED. A dual-mode interface supports either an I2C interface or 2-bit logic bus, allowing users to program the LED strings independently in hardware with external resistors or in software by writing data to the driver registers. The ADP1653, in a 3 mm x 3 mm LFCSP, is sampling now with production set for February 2007. Price is $1.45 each/1,000. ANALOG DEVICES INC., Wilmington, MA. (800) 262-5643.