Apple Inc.
Low Dropout Regulator with Feedforward Power Supply Noise Rejection Circuit

Abstract:

A voltage regulator circuit included in a computer system may include a switch device coupled between an input power supply node and a regulated power supply node. The switch device may change a value of a supply current flowing from the input power supply node and the regulated power supply node to regulate a voltage level of the regulated power supply node. A noise cancelation current may be feed forward onto a control terminal of the switch device to cancel noise on the regulated power supply node resulting from noise present on the input power supply node.