The FAN5029 is a highly efficient multi-phase synchronous buck switching regulator controller optimized for converting a 12V main supply into the core supply voltage required by high performance Intel processors. It uses an internal 8-bit DAC to read voltage identification (VID) code directly from the processor, which is used to set the output voltage between 0.5V and 1.6V. It uses a multi-mode PWM architecture to drive the logic-level outputs at a programmable switching frequency that can be optimized for VR size and efficiency. The phase relationship of the output signals can be programmed to provide 2-, 3-, 4-, or 5-phase operation, allowing for the construction of up to five complementary buck switching stages.