Boost Converter Manages Multiple High-Bright LEDs January 03, 2008
By way of an integrated 40V/1.2A FET switch, the TPS61165 boost converter drives up to three 1W LEDs in series from an input-voltage range of 3V to 18V, allowing users to manage multiple high-power LEDs in single-cell applications or point-of-load designs with a 9V or 12V bus. Brightness control is via a digital single-wire interface or a PWM signal. The digital interface programs an internal register to set LED current to one of 32 logarithmic steps. In addition to LEDs, the device drives backlight LEDs in displays up to 9" in diameter. Other features include a 1.2-MHz switching frequency and an efficiency of 90%. Also available, the TPS61160 and TPS61161 converters support input voltages from 3V to 18V and integrate a 0.6A current switch. The TPS61160 drives up to six LEDs with 26V open LED protection while the TPS61161 drives up to 10 LEDs with 38V open LED protection. Available in 2 mm x 2 mm QFN packages, prices for the TPS61160, TPS61161, and TPS61165 are $0.85, $1, and $1.40 each/1,000, respectively. TEXAS INSTRUMENTS INC., Dallas, TX. (800) 477-8924.
