The ADP31981 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 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 multimode 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-, or 4-phase operation, allowing for the construction of up to four complementary buck switching stages.The ADP3198JCPZ-RL also includes programmable no load offset and slope functions to adjust the output voltage as a function of the load current, optimally positioning it for a system transient. The ADP3198JCPZ-RL 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 ADP3198JCPZ-RL has a built-in shunt regulator that allows the part to be connected to the 12 V system supply through a series resistor.The ADP3198JCPZ-RL is specified over the extended commercial temperature range of 0℃ to 85℃ and is available in a 40-lead LFCSP.
Feature
Selectable 2-, 3-, or 4-phase operation at up to 1 MHz per phase ±11 mV worst-case differential sensing error over temperature Logic-level PWM outputs for interface to external high power drivers Enhanced PWM flex mode for excellent load transient performance 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
