Patent ID: 7619444

Claim:
A method of controlling the level of voltage applied to one or more circuit components of an integrated circuit (IC) device having core logic powered by a first supply voltage and I/O logic powered by a second supply voltage, comprising: determining if the first supply voltage is below a predetermined voltage level with a sense circuit by receiving the first supply voltage as an input to a logic circuit powered from an intermediate supply voltage having a voltage level between ground and the second supply voltage; if the first supply voltage is not below the predetermined voltage level, supplying one or more regulated voltage signals to the one or more circuit components via a voltage regulator powered by the second supply voltage and configurable via control signals generated by the core logic, including: supplying a high regulated voltage signal to switch a transistor in a pull-down circuit; and supplying a low regulated voltage signal to switch a transistor in a pull-up circuit, wherein the pull-down and pull-up circuits are used to drive an input/output (I/O) pad of the IC device and values of the high and low regulated voltage signals are dependent, at least in part, on control signals generated by the core logic that are used to configure a programmable reference voltage generator; and if the first supply voltage is below the predetermined voltage level, supplying the one or more regulated voltage signals to the one or more circuit components via the sense circuit, wherein each of the regulated voltage signals has a voltage level below a rated tolerance voltage of the one or more circuit components, and the one or more regulated voltage signals supplied by the sense circuit have a substantially similar voltage level that is approximately one half the voltage level of the second supply voltage.