A comprehensive submicrometer MOST delay model and its application to CMOS buffers

In this paper, an accurate delay model for MOS transistors in submicrometer CMOS digital circuits is presented. It takes into account a ramp shape input voltage and a feedforward capacitive coupling between gate and drain nodes, along with the main second-order effects present in short-channel MOS transistors. The proposed model shows an average agreement with SPICE simulations of 3% in the calculation of the propagation time, tested on a minimum inverter with a 0.7-/spl mu/m CMOS reference technology for a wide range of input voltage slopes. An example of application in optimization algorithms regarding CMOS tapered buffers is also reported. A maximum error ranging from 3-6% with respect to SPICE has been found for the optimized circuits.