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, having 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 either 1x, 1.5x, or 2x mode. The charge pump automatically switches between 1x/1.5x/2x modes, based on the input voltage, to maintain sufficient drive for the LED anodes at the highest power efficiency. |