Demonstration circuits 721A-A and 721A-B are high current step-down converters for Intel VRM/VRD10 and VRM9 processor power applications. The 6-phase DC721A-A features two current-mode PolyPhaseTM controllers, the LTC3738CUHF (3-Phase Buck Controller for Intel VRM9/VRM10 with Active Voltage Positioning and the the LTC3731CUH (3-Phase, 600kHz, Synchronous Buck Switching Regulator Controller) and provides up to 120A output current. The input voltage is from 8V to 14V and the output voltage is controlled by the VID setting.