National Semiconductor Corp. today introduced the industry's smallest 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 LEDs in series, illuminating larger displays in portable media devices such as smartphones. The LM3530 is offered in a 12-bump micro SMD package measuring just 1.615 mm x 1.215 mm x 0.425 mm.

National's LM3530 LED driver employs sophisticated 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.

In a pair of tests, National compared the energy consumption of a backlight illuminating a 3.5-inch iPod touch display with and without National's LM3530 LED driver.

The evaluation was conducted using typical multimedia downloadable material, in this case an episode from a television series and a trailer from a popular movie. Results showed the LM3530 achieved a power savings of 43 percent and 55 percent, respectively, over traditional backlighting. The predominately darker picture in the movie trailer garnered further power savings because the backlight was reduced more frequently for dark images.

The LM3530 brings power savings to the serial implementation of large display backlighting. For parallel charge pumps, National will offer a product with a similar feature set in October 2009. For more information or to order samples and an evaluation board, visit http://www.national.com/pf/LM/LM3530.html.