Controlling the design of critical circuits in VLSI circuits

摘要

Controlling the design of critical circuits (e.g. latches, clock generators and specialized logic) that are used in microprocessor and other very large scale integrated circuits. The chip is designed using circuits from at least one library of predetermined circuits that can be incorporated into the chip, the predetermined circuits having predetermined specifications regarding operational performance. Designers can apply modifications to the critical circuits in a controlled manner such that the changes are easy to implement and virtually guaranteed to be correct. The invention comprises a method of performing limited modifications to such a critical circuit to alter its characteristics in a controlled manner, and thereafter checking the resulting modified circuit with a circuit simulator for conformance to predetermined specifications that have been assembled for this library critical circuit.