FAN5032

FAN5032 8-Bit Programmable 2 to 4 Phase Synchronous Buck Controller April 2006 FAN5032 8-Bit Programmable 2 to 4 Phase Synchronous Buck Controller Features ■ Selectable 2, 3, or 4 phase operation at up to 1MHz ■ ■ ■ ■ ■ ■ ■ ■ 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 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. 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 The FAN5032 also includes programmable no-load offset and droop functions to adjust the output voltage as a ...