VLSI Circuit Simulation

The field of VLSI circuit simulation addresses the problem of the inadequacy of standard circuit simulation programs to handle the large circuits that are now being designed. This chapter begins with a brief discussion of standard circuit simulators, and then proceeds to cover the two main approaches that have been taken to simulate VLSI circuits. The second section considers simulators that have been tailored to exploit the properties of large digital MOS networks, the major components of today’s VLSI circuits. A discussion of Waveform Relaxation, a specialized algorithm exploited later in this book, is included in this section. The third section considers algorithms that trade substantial accuracy to obtain increased speed. Rough timing simulators have been developed that use very simplifiied circuit models to inject unmeasured uncertainty, and bounds on the responses of very simple circuit models have been used to inject measured uncertainty.