Efficient on-chip delay estimation for leaky models of multiple-source nets

An algorithm for efficiently computing an Elmore approximation in a leaky RC tree which may contain any number of uniformly distributed RC segments is presented. This algorithm works in the frequency domain, and it owes much of its efficiency to the fact that intermediate results leftover from computation of the driving-point admittance approximation are reused. The algorithm for computing an Elmore approximation starts at the output of the active source gate and proceeds downstream, in a finite sequence of steps, to the input of a specified load gate