GENERAL DESCRIPTION

The ADP31891 is a highly efficient multi-phase synchronous buck switching regulator controller optimized for converting a 12 V main supply into the core supply voltage required by high performance Intel processors. It uses an internal 8-bit DAC to read a voltage identification (VID) code directly from the processor, which is used to set the output voltage between 0.5 V and 1.6 V.

This device 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 relation ship 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.

FEATURES

Selectable 2-, 3-, 4-, or 5-phase operation at up to 1 MHz per phase

±7.7 mV worst-case differential sensing error over temperature

Logic-level PWM outputs for interface to external high-power drivers

Active current balancing between all output phases

Built-in power good/crowbar blanking supports on-the-fly VID code changes

Digitally programmable 0.5 V to 1.6 V output— supports both VR10.x and VR11 specifications

Programmable short-circuit protection with programmable latch-off delay

APPLICATIONS

Desktop PC power supplies for Next generation Intel® processors VRM modules