—This paper presents a design method of easily testable AND-EXOR networks. It is an improvement of Reddy and Saluja-Reddy's methods, and has the following features: 1) The network uses generalized Reed-Muller expressions (GRMs) instead of Positive Polarity Reed-Muller expressions (PPRMs). The average number of products for GRMs is less than half of that for… (More)
In some cases, minimum Sum-Of-Products (SOP) expressions of Boolean functions can be derived by detecting decomposition and observing the functional properties such as unateness, instead of applying the classical minimization algorithms. This paper presents a systematic study of such situations and develops a divide-and-conquer algorithm for SOP… (More)
A realization of multiple-output logic functions using a RAM and a sequencer is presented. First, a multiple-output function is represented by an encoded characteristic function for non-zeros (ECFN). Then, it is represented by a cascade of look-up tables (LUTs). And finally, the cascade is simulated by a RAM and a sequencer. Multiple-output functions for… (More)
—This paper proposes an architecture and a synthesis method for high-speed computation of fixed-point numerical functions such as trigonometric, logarithmic, sigmoidal, square root, and combinations of these functions. Our architecture is based on the lookup table (LUT) cascade, which results in a significant reduction in circuit complexity compared to… (More)
This paper shows four different methods to evaluate multiple-output logic functions using decision diagrams: SBDD, MTBDD, BDD for characteristic functions (CF), and BDDs for ECFNs (Encoded Characteristic Function for Non-zero outputs). Methods to compute average evaluation time for each type of decision diagrams are presented. By experimental analysis using… (More)
This paper surveys seven types of TDDs: General TDD, SOP TDD, ESOP TDD, AND TDD, prime TDD, EXOR TDD, and Kleene TDD. We give new denitions for SOP TDDs and ESOP TDDs and introduce unifying terminology. After showing some theore m s o n c omplexities, we compare the sizes of these TDDs using benchmark functions. Finally, we review important works on TDDs.
A logic function f has a disjoint bi-decomposition i f can be represented as f = h(g 1 (X 1); g 2 (X 2)), where X 1 and X 2 are disjoint set of variables, and h is an arbitrary two-variable logic fuction. f has a non-disjoint bi-decomposition i f can be represented as f(X 1 ; X 2 ; x) = h(g 1 (X 1 ; x); g 2 (X 2 ; x)), where x is the common variable. In… (More)
A multiple-output function can be represented by a binary decision diagram for characteristic function (BDD for CF). This paper presents a new method to represent multiple-output incompletely specified functions using BDD for CF. An algorithm to reduce the widths of BDD for CFs is presented. This method is useful for decomposition of incompletely specified… (More)