All digital power supply system and method that provides a substantially constant supply voltage over changes in PVT without a band gap reference voltage

摘要

An all digital power supply system provides a supply voltage to semiconductor circuits. The power supply system utilizes an up/down counter and a pulse width modulator to output a signal into a LC network that generates the supply voltage. The width of the pulses output by the pulse width modulator are defined by an encoder that generates width information in response to a propagation delay detector that measures the propagation delay of a first clock signal when clocked by a second clock signal. The system supplies the optimum or minimum required voltage to insure that a critical path through a digital chip is met over process, voltage, and temperature (PVT) variations without the use of a band gap reference voltage source. A state machine is also used to counteract oscillations introduced by start up and load transients, thereby eliminating the need for a proportional integrator differentiator (PID).