Enhanced voltage regulation with power supply disable capability for low-power operation

摘要

A method and apparatus is provided that facilitates low-power consumption during a suspend mode of operation of an integrated circuit (IC), while substantially eliminating current paths within the IC that may be created should any of the power supplies be deactivated during the suspend mode. Deactivation of one or more power supplies during a normal mode of operation is also facilitated, whereby current paths created by the deactivated power supplies are also eliminated. Voltage bias circuitry is added to certain voltage regulators within the IC, so as to maintain those voltage regulators inactive due to a drop in voltage magnitude that is sensed when one or more power supplies are disabled. In addition, a well bias circuit is employed to maintain the substrate bias potential of certain devices within the voltage regulators and associated amplifiers to a fixed potential depending upon the operational mode of the IC.