Patent ID: 7043705

Claim:
A method of estimating a plurality of current density parameters characterizing electrical signals that would be transferred on a signal lead of an integrated circuit, said signal lead connecting a driver cell to a load cell, said method being performed in a computer aided design (CAD) tool used to design said integrated circuit, said method comprising: modeling said driver cell in the form of a triangle signal and said signal lead in the form of an impedance network; simulating an operation of said integrated circuit by providing said triangle signal as an input to said impedance network; and measuring electrical signals on said impedance network to estimate said plurality of current density parameters on said signal lead; receiving a first plurality of parameters characterizing operation of said driver cell; computing a second plurality of parameters characterizing said triangle signal based on said first plurality of parameters; and wherein said triangle signal contains a positive peak and a negative peak, said first plurality of parameters comprises an average current (Javg), a root mean square current (Jrms), a positive peak level (Jpkp), and a negative peak level (Jpkn), wherein durations of a positive portion of said triangle (Ta) and a negative portion of said triangle (Tb) are computed according to the equations: Ta =[{6 T Jrms 2 +(8 T Javg Jpkn )}/{ Jpkp ( Jpkp+ 2 Jpkn )}]; and Tb=[ 2{6 T Jrms 2 −(4 T Javg Jpkp )}/{ Jpkn ( Jpkp+ 2 Jpkn )}]; wherein T represents periodicity.