Pseudocube-based expressions to enhance testability

Sum-of-Pseudoproduct (SPP) forms are new logic representations and have made it possible to represent Boolean functions with more smaller expression than standard Sum-of-Products (SOP) forms. Our experimental results show that SPP forms require many fewer products and literals than SOP and ESOP for practical networks. Moreover, we show that SPP forms are more testable than ESOP forms. Next, we propose EXOR-Sum-of-Pseudoproduct (ESPP) form. This form is an EXOR-AND-EXOR one and enhances the random pattern testability. Experimental results show that ESPP forms are more testable than SPP and ESOP. Furthermore, they have the new possibility of compactness of the networks. We derive an upper bound on the number of pseudo-products to realize an arbitrary n-variable function by ESPP form.