The FAN5033 device is a multi-phase buck switching regulator controller optimized to convert a 12V input supply to the processor core voltage required by high performance Intel® processors. It has an internal 8-bit 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 PWM signals to external MOSFET drivers that drive the switching power MOSFETs. The switching frequency of the design is programmable by a single resistor value. The number of phases can be programmed to support two- or three-phase applications.

The FAN5033 also includes programmable no-load offset and droop functions to adjust the output voltage as a function of the load current, as required by the Intel specifications. The FAN5033 provides an accurate and reliable short-circuit protection function with an adjustable over-current set point.

The FAN5033 is specified over the commercial temperature range of 0°C to +85°C and is available in a 32-lead MLP package.

• Selectable 2- or 3-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 with the 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

• Desktop PC/Server processor power supplies for existing and next-generation Intel processors
• VRM modules