Dec 2003Microsemi Corp.Request Info
Microsemi Corp. has introduced two integrated circuits combined in a compact surface-mount package that boost a low-voltage supply to drive a string of white or colored LEDs and provide an adjustable bias voltage for the LCDs that they illuminate. The LX1744 PFM boost controller provides an adjustable LED drive and one adjustable ± bias supply output; the LX1745 includes the LED drive and two adjustable bias supplies. The devices save space, cut system cost and are rated at better than 90% efficiency in handheld applications such as PDAs, smart phones, digital cameras and pagers. They feature a logic-controlled shutdown current of <1 µA and input voltage from 1.6 to 6.0 V. LED bias output voltage is adjustable up to ±15%.