The present invention is a system and method for statistical or
probabilistic static timing analysis of digital circuits, taking into
account statistical delay variations. The delay of each gate or wire is
assumed to consist of a nominal portion, a correlated random portion that
is parameterized by each of the sources of variation and an independent
random portion. Arrival times and required arrival times are propagated
as parameterized random variables while taking correlations into account.
Both early mode and late mode timing are included; both combinational and
sequential circuits are handled; static CMOS as well as dynamic logic
families are accommodated. The timing analysis complexity is linear in
the size of the graph and the number of sources of variation. The result
is a timing report in which all timing quantities such as arrival times
and slacks are reported as probability distributions in a parameterized
form.