Date: 25/08/2009

National's white LED driver with automatic backlight control based on ambient light

National Semiconductor has introduced the white light-emitting diode (LED) driver with dynamic display backlight control. The LM3530, a member of National's powerwise energy-efficient product family, drives up to 11 high-current LED lamps in series, illuminating larger displays in portable media devices such as smartphones.

The LM3530 LED driver employs ambient light-sensing algorithms and content-adjustable backlighting to optimize the display, realizing up to a 55 percent power saving over the common practice of driving the backlight at a constant brightness.

The LM3530 current-mode boost converter can supply up to 29.5 mA of power to 11 white LEDs from a single-cell Lithium-Ion battery. A wide degree of programmability via an I2C compatible interface enables to adjust for lighting effects such as fading, external ambient conditions and lighting level, brightness and image performance.

The LM3530's programmable ambient light response along with a separate pulse-width modulation (PWM) dimming input enable the backlight LED driver to determine lighting requirements and select between various dimming options, optimizing the light output for the given conditions. Logarithm and linear LED brightness mapping provides flicker-free dimming. A fixed-frequency, 500 kHz boost converter provides high efficiency over the LED current range.

Package: 12-bump micro SMD package
Price: Each $1.99 for 1k pieces
Availability: Now
For more details visit www.national.com/analog/led