A method and a system for validating initial conditions (ICs) generally
provided by a user when simulating a VLSI circuit are described.
Inconsistent ICs sets are detected and replaced by consistent subsets
thereof. The method selects the resistance and source values in a Norton
or Thevenin circuit used to enforce the IC, and detects when specified
ICs are inconsistent while preserving critical or fragile ICs when a two
DC-pass approach is used. It further correlates the set of consistent ICs
thus obtained with an equivalent circuit and simultaneously provides an
input for future use. This allows a user to be notified and given a
measure of how bad the inconsistencies are. Detecting inconsistencies is
achieved either by measuring the holding current or by measuring the
voltage drift if the two DC-pass approach is used.