Efficient Transition-Mode Boolean Characteristic Function with Its Application to Maximum Instantaneous Current Analysis

Circuit timing and power analysis are important in various aspects of circuit optimization. In order to solve the problem of finding input vectors to activate worst-case timing or power, a concept called timed characteristic function (TCF) was proposed, which can characterize logical and temporal conditions simultaneously. Traditionally TCF assumes the (one-vector) floating mode of operation. In this paper we extend TCF for the (two-vector) transition mode and propose an efficient way to construct transition-mode TCF. Also, we apply the TCF concept to the analysis of the maximum instantaneous current (MIC) of a circuit, where transition-mode TCF is used to formulate gates' switching conditions. The experimental results show that on average, the TCF technique can derive about 30% more accurate MIC results than random simulation does for combinational circuits