AAT2803

Six-Channel White LED Backlight Charge Pump with Flash General Description The AAT2803 is a dual charge pump designed to support both white LED backlight and flash applications for systems operating with lithium-ion/polymer batteries. The backlight charge pump is capable of driving up to six LEDs at a total of 180mA. The current sinks may be operated in group or in parallel for driving higher current LEDs. To maximize power efficiency, the charge pump operates in 1X, 1.5X, or 2X mode, where the mode of operation is automatically selected by comparing the forward voltage of each LED with the input voltage. AnalogicTech's AS2Cwire™ (Advanced Simple Serial Control™) serial digital input is used to enable, disable, and set current for each LED with a 16-level logarithmic scale plus four lowcurrent settings down to 50μA for optimized efficiency, with a low housekeeping current of only 50μA. The flash charge pump is a charge pump doubler with a regulated output voltage. It is designed to deliver 120mA of continuous current and up to 300mA of pulsed current. It has an independent enable pin for improved power savings. AAT2803 Features ChargePump™ VIN Range: 2.7V to 5.5V Dual Charge Pump: — Flash: Charge Pump Doubler — Backlight: Tri-Mode Charge Pump Backlight Charge Pump: — Programmable Current With Single GPIO — 16 Current Steps — 15/20/30mA Max Current — Four Low Current Settings — Individual Main/Sub-Group Control — Low IQ (50μA) for Low-Current Mode — ...