Nine-Channel LED Drivers Offer 93 Percent Efficiency
Thu, 10/07/2010 - 7:09am
Diodes Incorporated announced two, nine-channel LED drivers with internal charge-pumps for backlighting small-LCD screens, keypads and LED lights. Working from 2.7 V to 5.5 V and driving 20 mA, the applications include mobile phones and other portable consumer devices. Driving three groups of three LED channels and its three independent PWM dimmable control inputs the AL3158 provides a simple drive for RGB LEDs. The AL3159 with its three-wire logic decoding of LED current control enables the driving of nine LEDs for illuminating LCD screens and LED indicator control. The inductor-less solution requires only three external capacitors to complete the driver circuit. High levels of functional integration coupled with thin QFN packages mean that these devices save board space and reduce manufacturing costs. The devices offer up to 93 percent power efficiency maximizing battery life, and feature 1 percent current matching accuracy between channels to deliver an extremely even, consistent screen image.