Aug 6 2010
Fairchild Semiconductor has announced the new linear LED drivers, the FAN5622/24/26, that are suitable for backlighting keypads and LCD displays in portable electronics. The FAN5622/24/26 LED drivers are current-sink drivers with two, four, and six channels, respectively.
The drivers’ design decreases count of the components by avoiding the need for supplementary passive components, which are used in series-boost LED drivers, and charge pumps. The drivers have a low 50 mV dropout voltage, hence they allow LED driving without using flyback capacitors or inductor.
The LED-brightness output levels are programmed with the help of a single-wire control interface. This interface allows programming 32 linear dimming steps and switching off and on the LEDs using digital pulses. This results in a higher dimming resolution. The drivers have a 92% high peak efficiency, which increases the battery life.
The FAN5622/24/26 LED drivers also include features such as shut-down current of less than 1µA, thermal and under-voltage protection, short-circuit, and wide input voltage range from 2.7 to 5.5 V.