SC623A

SC623A LED Light Management Unit POWER MANAGEMENT Features „ „ „ „ „ „ „ „ „ „ „ „ „ „ „ Charge Pump, 4 LEDs, 400mA Flash LED, and I2C Interface Description The SC623A is a high efficiency charge pump LED driver using Semtech’s proprietary mAhXLifeTM technology. Performance is optimized for use in single-cell Li-ion battery applications. The charge pump provides backlight current in conjunction with four matched current sinks. It also can supply continuous or bursted current to a flash LED using the dedicated flash driver current sink. The load and supply conditions determine whether the charge pump operates in 1x, 1.5x, or 2x mode. An optional fading feature that gradually adjusts the backlight current is provided to simplify control software. A flash-timeout feature disables the flash if active for longer than 1 second. The SC623A uses an I2C compatible serial interface. The interface controls all functions of the device, including backlight and flash currents. The flash/spotlight output is triggered via either the I2C interface or a dedicated pin. In sleep mode, the device reduces quiescent current to 100μA while continuing to monitor the serial interface. Total current reduces to 0.1μA in shutdown. Input supply voltage range — 3.0V to 5.5V Charge pump modes — 1x, 1.5x and 2x Four programmable current sinks with 32 steps from 0.5mA to 25mA Flash LED — 400mA max in flash mode, 250mA max continuous for spotlight Charge pump frequency — 250kHz I2C compatible interface — up ...