Abstract not found

We show how charge distribution effects in MOS transistors are reflected only correctly by models based on the physical properties of the device. Hence one has to consider carefully the impact of modeling to obtain correct results for MOS circuits by numerical simulation. Additionally, the choice of an appropriate integration scheme is essential for both reliable and efficient simulation results. To spotlight these influences, we use a charge pump as an instructive test circuit and discuss a variety of modeling approaches.

Just about all electrical engineers have some form of encounter with SPICE, Simulation Program with Integrated Circuit Emphasis. It could be in a homework assignment during the undergraduate studies, or as an essential part of circuit design at work. As its full name suggests, SPICE is a computer program that accepts a circuit schematic as input and outputs the simulated circuit behaviors. The simulation can be performed under the nonlinear dc, nonlinear transient and linearized ac operating conditions. The circuit may contain resistors, capacitors, inductors, mutual inductors, independent voltage and current sources, dependent sources, lossless and lossy transmission lines, switches, uniform distributed RC lines, and various semiconductor devices including MOSFETs (metal oxide semiconductor fieldeffect transistors). The original SPICE program, SPICE 1, was developed at University of California, Berkeley, and released for public use in May, 1972. By 1975, after the next major release, called SPICE2, SPICE was in widespread use and adopted by most integrated circuit manufacturers. SPICE2 was written in Fortran. With the advent of UNIX computers in the 1980s it became increasingly obvious that SPICE