Sep 30 2010
Developer and provider of semiconductor products, Diodes Incorporated, has rolled out two new LED drivers that feature internal charge-pumps for backlighting LED lights, keypads and small LCD screens.
The LED drivers, AL3158 and AL3159, operate from 2.7 V to 5.5 V and drive a frequency of 20 mA. The drivers are ideal for portable consumer instruments such as mobile phones. The AL3158, driving three sets of 3-LED channels and the three PWM dimmable control inputs, offers a convenient drive for RGB LEDs. With a flexible 3-wire logic decoding of the LED current control, the AL3159 facilitates the driving of 9-LEDs to light up the LED indicator control and LCD screens.
The inductor-less LED driver solution needs three external capacitors to finish the driver circuit. The drivers feature small QFN packages combined with high-levels of functional integration to decrease manufacturing expenses and save board space. The LED drivers have current matching precision of 1% between the channels; maximize battery life and provide a maximum power efficiency of 93% to deliver a consistent and even screen image.
Over voltage protection, thermal and under-voltage lockout and LED open and short-circuit protection are offered on every channel outputs to enhance reliability. A soft start operation provided by the drivers decrease power supply and maximizes the operating life of the battery. The drivers are lead-free, thermally improved and come in a 20-pin, 0.6 mm high, and 3 mm x 3 mm QFN package.