Analog Devices ADM8843ACPZ1-R7

LED Driver, 4-Segment, CMOS

The ADM8843 uses charge pump technology to provide the power to drive up to four LEDs. The LEDs are used for...

The ADM8843 uses charge pump technology to provide the power to drive up to four LEDs. The LEDs are used for backlighting a color LCD display that has regulated constant current for uniform brightness intensity. The main display can use up to three LEDs, and the sub display uses one LED. The CTRL1 and CTRL2 digital input control pins control the shutdown operation and the brightness of the main and sub displays. To maximize power efficiency, the charge pump can operate in 1×, 1.5×, or 2× mode. The charge pump automatically switches among 1×/1.5×/2× modes, based on the input voltage, to maintain sufficient drive for the LED anodes at the highest power efficiency. Improved brightness matching of the LEDs is achieved by a feedback pin that senses individual LED current with a typical matching accuracy of 0.3%. Applications Cellular phones with main and sub displays White LED backlighting Camera flash/strobes and movie light applications Micro TFT color displays DSC PDAs