The LP55231 is a 9-channel LED driver designed to produce lighting effects for mobile devices. A high-efficiency charge pump enables LED driving over full Li-Ion battery voltage range. The device is equipped with an internal program memory, which allows operation without processor control.
The LP55231 has an I2C-compatible control interface with four pin-selectable addresses. The INT pin can be used to notify processor when a lighting sequence has ended (interrupt -function). Also, the device has a trigger input interface, which allows synchronization, for example, between multiple LP55231 devices. Excellent efficiency is maintained over a wide operating range by autonomously selecting the best charge pump gain based on LED forward voltage requirements. The device is able to automatically enter power-save mode when LED outputs are not active, thus lowering idle current consumption down to 10 µA (typ). Only four small and low-cost ceramic capacitors are required.
Three Independent Program Execution Engines, 9 Programmable Outputs With 25.5 mA Full-Scale Current, 8-bit Current Setting Resolution and 12-bit PWM Control Resolution
Adaptive High-Efficiency 1x/1.5x Fractional Charge Pump - Efficiency up to 94%
LED Drive Efficiency Up to 93%
Charge Pump With Soft Start and Overcurrent/ Short-circuit Protection