Description
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 high-performance 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.

FEATUREs
■ Selectable 2, 3, or 4 phase operation at up to 1MHz per phase
■ ±7.7mV worst-case differential sensing error over temperature
■ Active current balancing between the output phases
■ Power good and crowbar blanking supports on-the-fly VID code changes
■ 0.5V to 1.6V output
■ Fully compliant to Intel® VR10 and VR11 specifications
■ Selectable VR10 extended (7 bit) and VR11 (8 bit) VID tables
■ Programmable soft-start ramp
■ Programmable short-circuit protection and latch-off delay

Special Features
■ 300mV OVP and crowbar threshold

APPLICATIONs
■ Desktop PC/server processor power supplies for existing and next-generation Intel processors
■ VRM modules