Further considerations on the complexity of digital simulators

The author discusses the relationship between the complexity of digital simulators and the complexity of the circuits on which those simulators have to operate. He considers very-large scale integrated (VLSI) circuits of increasing complexity; for those circuits, the dynamics is computed using a digital hardware simulator exploiting parallelism and executing pipelined operations. Two classes of digital circuits are investigated. For both of them it is shown that, given a theoretical simulator, even if the complexity of the simulator increases as fast as the complexity of the circuit, the complexity of the simulation, in terms of elementary computation steps, still increases. Disturbing effects and scaling down effects that may further increase the computational complexity are taken into account in the complexity analysis