The FAN5032 is a controller for a multi-phase buck switching regulator optimized to convert a 12V input supply to the processor core voltage required by highperformance Intel processors. It has an internal 8-bit digital to analog converter (DAC) that converts a digital voltage identification (VID) code, sent from the processor to set the output voltage between 0.5V and 1.6V in 6.25mV steps. It outputs a pulse-width modulated (PWM) signal to external MOSFET drivers that, in turn, drive the switching power MOSFETs. The switching frequency of the design is programmable by a single resistor value and the number of phases can be programmed to support 2, 3, or 4 phase applications.