The ADP3164 is a highly efficient 4-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. The ADP3164 uses an internal 5-bit DAC to read a voltage identification (VID) code directly from the processor, which is used to set the output voltage between 1.1 V and 1.85 V. The ADP3164 uses a current mode PWM architecture to drive the logic-level outputs at a programmable switching frequency that can be optimized for VRM size and efficiency. The four output phases share the dc output current to reduce overall output voltage ripple. An active current balancing function ensures that all phases carry equal portions of the total load current, even under large transient loads, to minimize the size of the inductors.