On decomposition of Kleene TDDs

Kleene-TDDs are useful for evaluating logic functions in the presence of unknown inputs, 0 or 1. Although Kleene-TDD-based logic simulation is promising, the size of Kleene-TDD for an n-variable function is O(3/sup n//n). Thus, when n is large, the Kleene-TDDs are often too large to build. In this paper, we propose several methods to decompose Kleene-TDDs. By using this method, we can generate smaller Kleene-TDDs for sub-functions independently to reduce the necessary memory. Preliminary experimental results show that the effectiveness of the presented approach.