White LED Driver Reduces Power Consumption By Up To 55%

The LM3530 is claimed to be the industry’s smallest white LED driver with dynamic display backlight control. It’s a member of National’s PowerWise energy-efficient product family, drives up to 11 high-current LEDs in series to illuminate larger displays in portable media devices such as smartphones. The LM3530 employs sophisticated ambient light-sensing algorithms and content-adjustable backlighting to optimize the display and realize up to a 55% power saving over the common practice of driving the backlight at a constant brightness. The fixed-frequency, 500-kHz, current-mode boost converter can supply up to 29.5 mA of power to 11 white LEDs from a single-cell Lithium-Ion battery. Programmability via an I²C compatible interface enables the designer to adjust for lighting effects such as fading, external ambient conditions, lighting level, and brightness and image performance. Logarithm and linear LED brightness mapping provides flicker-free dimming. The LM3530 is offered in a 12-bump micro SMD package measuring 1.615 mm x 1.215 mm x 0.425 mm. Available now, the LM3530 costs $1.99 in 1000-unit quantities. NATIONAL SEMICONDUCTOR CORP., Santa Clara, CA. (800) 272-9959.