A novel approach to charge-based non-quasi-static model of the MOS transistor valid in all modes of operation

This paper presents a new set of exact analytical expressions for the small signal analysis of the non-quasi-static operation of the MOS transistor. T his model is derived from a standard charge-based description, with the hel p of the EKV compact model [Enz C, Krummenacher F, Vittoz E. Analog Integ C ircuits Signal Process 1995;8:83-114.] formalism. For the first time, it gi ves simple expressions for all AC parameters which are valid in all operati ng modes, from weak to strong inversion and conduction to saturation. The model is derived from physics and only relies on the very few basic ass umptions needed for a charge-based compact model. The results are written i n the form of a normalized transadmittance matrix which is expressed in ter ms of normalized variables (currents and frequency), so that they are indep endent of the process parameters. From this exact approach, simpler first- and second-order approximations, dedicated to circuit simulation tools, hav e been obtained. Finally, the theoretical results have been compared with m easurements showing a very good agreement with measurements. (C) 2000 Elsev ier Science Ltd. All rights reserved.