Boost Converter manages multiple high-brightness LEDs

2nd January 2008

ES Admin

0 0

Texas Instruments has introduced a high-brightness LED driver with an integrated 40V, 1.2A switch that can drive up to three 1W LEDs in series. The new TPS61165 device's high-performance features and input voltage range of 3 to 18V allow designers to efficiently manage multiple high-power LEDs used in single-cell, battery-powered applications or point-of-load designs with a 9 or 12V bus.

The TPS61165 allows LED brightness to be controlled by a digital single-wire interface or pulse width modulating (PWM) signal. The digital interface can program an internal register to set the LED current to one of the 32 logarithmic steps. The converter also comes with built-in protection features, such as open LED protection, soft-start, over-current limit and over-temperature protection.

In addition to driving illumination LEDs, the TPS61165 can drive backlight LEDs for media form factor displays up to 9 inches in diameter, such as those used in ultra-mobile PCs and LCD photo frames, industrial laser diodes or medical and industrial lighting.

TI also introduced its new TPS61160 and TPS61161 converters that support input voltages from 3-V to 18-V. Both devices integrate a 0.6-A current switch and target portable and battery powered applications with small displays, such as small 3-inch or 4-inch LCD display backlighting in portable game players, GPS systems and smart phones. The TPS61160 drives up to six LEDs with 26-V open LED protection, while the TPS61161 drives up to 10 LEDs with 38-V open LED protection. As with the TPS61165, the brightness of the LED can be controlled by a singe-wire digital interface or PWM signal, and analog dimming eliminates noise.