The R1280D002X Series are 2-channel PWM Step-up (as Channel 1)/Inverting (as Channel 2) DC/DC converter controllers with CMOS process. Each of the R1280D002X Series consists of an oscillator, a PWM control circuit, a reference voltage unit, an error amplifier, a reference current unit, a protection circuit, and an under voltage lockout (UVLO) circuit. A high efficiency Step-up/Inverting DC/DC converter can be composed of this IC with inductors, diodes, power MOSFETs, resisters, and capacitors. Each Output Voltage can be adjustable with external resistors, while soft-start time can be adjustable with external capacitors..