The TPS60250/2 are high efficiency, constant frequency charge pump DC/DC converters that use dual mode 1x and 1.5x conversions to maximize efficiency over the input voltage range. The devices drive up to five white LEDs for the main display and up to two white LEDs for the sub display with regulated constant current for uniform intensity. By utilizing adaptive 1x/1.5x charge pump modes and very low-dropout current regulators, the TPS60250/2 achieve high efficiency over the full 1-cell lithium-battery input voltage range. Four enable inputs, ENmain, ENsub1, ENsub2, and ENaux, available through the I2C, are used for simple on/off controls for the independent main, sub1, sub2, and DM5 displays, respectively. To lower the operating current when using one sub display LED, the devices provide completely separate operation for the sub display LEDs.