APPARATUS AND METHOD FOR CONTROLLING THE PROPAGATION DELAY OF A CIRCUIT BY CONTROLLING THE VOLTAGE APPLIED TO THE CIRCUIT

摘要

The voltage applied to an integrated circuit is controlled by a temporal process monitor formed as part of the integrated circuit. The temporal process monitor includes a voltage controlled oscillator for producing a first output signal having a first period. A comparator compares the first period to one or more reference values. Should the first period be greater than a first selected reference value the comparator sends a signal to increase the voltage being supplied to the integrated circuit. Should the first period be less than a second selected reference value, the comparator sends a signal to decrease the voltage applied to the integrated circuit. In some embodiments a scaling circuit is provided for producing a second output signal having a second period different from (typically but not necessarily longer than) the first period. By placing the temporal process monitor on an integrated circuit chip, process variations and environmental factors which affect the performance of the integrated circuit can be automatically compensated so that the integrated circuit performs within specifications. Two or more temporal process monitors can be placed on a single integrated circuit chip or on different integrated circuit chips and the longest period produced by the temporal process monitors can be used to control the voltage supplied to all the sections of the integrated circuit chip associated with the temporal process monitors or to all the integrated circuit chips associated with the temporal process monitors. In some embodiments voltages related to the frequency of a temporal process monitor signal and the frequency of a fixed frequency clock are provided to an error amplifier, which changes the voltage applied to the integrated circuit such that the two frequencies are the same.