APPARATUS AND METHODS FOR LOW VOLTAGE HIGH PSRR SYSTEMS

摘要

Provided herein are apparatus and methods for low voltage high power supply rejection ratio (PSRR) systems. A charge pump converts a supply voltage to a larger charge pump voltage and provides the charge pump voltage to a circuit subsystem. The charge pump voltage is regulated to a state dependent reference. In the steady state the charge pump voltage is regulated with respect to an output voltage of the circuit subsystem; in this way PSRR of the circuit subsystem is enhanced.

主权项

1. An apparatus comprising:
a supply node configured to receive a supply voltage; a charge pump configured to convert the supply voltage to a charge pump voltage; a circuit subsystem configured to receive the charge pump voltage at a subsystem supply node and to provide an output voltage at an output node, wherein the circuit subsystem is configured to transition from a subsystem transient state to a subsystem steady state, and wherein in the subsystem steady state the output voltage has a steady state output value; and a charge pump regulation control module configured to regulate the charge pump voltage with respect to a state dependent reference, wherein the state dependent reference has a transient state reference value and a steady state reference value, and wherein the steady state reference value is the steady state output value.