A flexible hierarchical piecewise linear simulator

In this paper, a piecewise linear (PL) simulator, called PLANET, will be presented. New features in contrast to other existing (piecewise linear) simulators are a flexible hierarchical data structure which retains the hierarchy in the simulated system, and the use of a simplified form of the Katzenelson algorithm to solve the circuit equations. Owing to the PL-concept, the simulator is capable of performing full mixed-level and mixed-mode simulations. Due to the new concept, the hierarchically organized simulator can be used by advantage in a hierarchical design environment. The replacement of a single component by a subcircuit becomes facile. The hierarchical representation of a circuit or system makes it easy to exploit latency in a circuit by means of numerical integration techniques having variable stepsize or by employing an event-driven approach.