Efficient output waveform evaluation of a CMOS inverter based on short-circuit current prediction

A novel approach for obtaining the output waveform, the propagation delay and the short-circuit power dissipation of a CMOS inverter is introduced. The output voltage is calculated by solving the circuit di erential equation only for the conducting transistor while the e ect of the short-circuit current is considered as an additional charge, which has to be discharged through the conducting transistor causing a shift to the output waveform. The short-circuit current as well as the corresponding discharging current are accurately predicted as functions of the required time shift of the output waveform. A program has been developed that implements the proposed method and the results prove that a signi cant speed improvement can be gained with a minor penalty in accuracy. Copyright ? 2002 John Wiley & Sons, Ltd.