LED Drivers Suit Mobile Devices

Leadis Technology’s LDS8866, LDS8865, and LDS8864 represent a family of charge-pump-based LED drivers for mobile backlighting applications. Based on the powerLite 50-mV LDO current regulator, the family supports up to six LEDs with a maximum current of 32 mA per channel. The on-chip non-volatile memory also allows users to define the maximum current of each of three LED banks, eliminating the need for external resistors. On-chip dimming of LED currents is controlled through a PWM interface.

The devices solve one of the most significant problems associated with charge-pump-based LED drivers, namely the transition between the high-efficiency state (1X mode) and the lower-efficiency states. Through the low dropout voltage, battery life can be extended by up to 20%, and the LDS8866, LDS8865, and LDS8864 have efficiencies of 95%, 93% and 90%, respectively. All devices are available in a 16-lead 3-mm x 3-mm TQFN package with a maximum height of 0.8 mm.