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The main point of the synthesis method M1 of one-level combinatorial circuits consists in a partition of set Y* on minimum number T of subsets Y1..., YT so that were fulfilled necessary and sufficient conditions of implementation on one PAL (function box CPLD) of all functions of subset Y1, t =

In subsequent functions of each subset Y1, t=

Positive qualities of method M1 are the following:

It is created combinatorial circuit of the maximum speed limited only to time of passing of signals from inputs on outputs PLD;
All output signals have identical time of creation;
Method allows to apply separate minimization of Boolean functions which quality is higher, than joint minimization;
The method can be applied in digital systems both with direct logic and with inverse logic;
For implementation of a Booleen Function System the minimum number of macrocells the PLD, equal to number of realizable functions.

At the same time method M1 has the following disadvantages:

The method is applied only in enough simple Booleen Function Systems;
High total cost of implementation of a Booleen Function System on number used PAL or function boxes CPLD.

Thus, method M1 is most effective at synthesis concerning simple combinatorial circuits for any classes PLD in digital systems both from direct logic, and with inverse logic.

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