Synthesis Of MultiLevel Circuits Using EXOR-Gates
Bernd Steinbach1995
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Abstract
There are many methods for the synthesis of logical functions. All these methods can be divided into two classes the first one is Two-Level Logic Synthesis and the second one is Multi-Level Logic Synthesis. The multi-level circuits and their structure are easier for practical realization if there is a large number of variables. In this paper we concentrate on a part of the second class - synthesis of multi-level-circuits with EXOR-gates. We present six methods for EXOR-decomposition for both, completely and incompletely specified functions. In detail, we give an iterative algorithm for checking and calculating the EXOR - groupability for the incompletely specified functions relating to sets of variables. Using this method, it is possible to fully utilize the characteristics and properties of incompletely specified functions enabling synthesis of very efficent circuits.
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