A circuit incorporating a current starved ring oscillator is coupled to a power gate switch in an integrated circuit. The circuit incorporating the current starved ring oscillator amplifies a voltage difference between a virtual ground associated with the power gate switch and ground, and converts the difference to a frequency. Digital logic monitors the output of the ring oscillator using a counter and a reference clock. Control circuitry controls operation of the integrated circuit in dependence on the monitored conditions associated with the power gate switch. A method monitors a virtual ground voltage across a power gate switch in an integrated circuit; and controls operation of the integrated circuit in dependence on the monitored virtual ground voltage.