SC627

The SC627 is a high effi ciency 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 fl ash LED using the dedicated fl ash 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 fl ash-timeout feature disables the fl ash if active for longer than 1 second. The SC627 also provides two low-dropout, low-noise linear regulators for powering a camera module or other peripheral circuits.

The SC627 uses the proprietary SemWire^TM single wire interface. The interface controls all functions of the device, including backlight and fl ash currents as well as two LDO voltage outputs. The single wire implementation minimizes microcontroller and interface pin counts. The fl ash/spotlight output is triggered via either the SemWire interface or a dedicated pin.

In sleep mode, the device reduces quiescent current to 100A while continuing to monitor the serial interface. The two LDOs can be enabled when the device is in sleep mode. Total current reduces to 0.1A in shutdown.