ADP3197

The ADP31971 is a highly efficient multiphase synchronous buck switching regulator controller optimized for converting a 12 V main supply into the core supply voltage required by high perform-ance, Advanced Micro Devices, AMD processors. It uses an internal 6-bit digital-to-analog converter (DAC) to read a voltage identification (VID) code directly from the processor, which is used to set the output voltage between 0.3750 V and 1.55 V. It uses a multimode pulse-width modulation (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-phase or 3-phase operation, allowing for the construction of up to three complementary buck switching stages.

The ADP3197 supports a programmable slope function to adjust the output voltage as a function of the load current so it is always optimally positioned for a system transient. This can be disabled by connecting the LLSET pin to the CSREF pin.

The ADP3197 also provides accurate and reliable short-circuit protection, adjustable current limiting, and a delayed power-good output that accommodates on-the-fly output voltage changes requested by the CPU.

The ADP3197 has a built-in shunt regulator that allows the part to be connected to the 12 V system supply through a series resistor.

The ADP3197 is specified over the extended commercial tempera-ture range of 0°C to 85°C and is available in a 32-lead LFCSP.