Apple Inc.
Noise suppression in voltage regulator circuits

Abstract:

A power converter circuit included in a computer system may charge and discharge a switch node coupled to a regulated power supply node via an inductor. During a discharge cycle, the power converter circuit may sense a current being discharge from the regulated power supply node through the inductor into a ground supply node. The power converter circuit may also sense a noise current flowing in the ground supply node, and generate a control current using both the current being discharge and the noise current. Using the control current, the power converter circuit may halt the discharge cycle.