US 6,557,146 B1 · Method for the comparison of electrical circuits

Abstract

Various phases of the circuit design are specified in different notations, whereby each notation is based on the same circuit. Since the notations arise successively during the circuit design, whereby the circuit design covers a considerable time span, it should also be assured that a first change in a notation of an early phase corresponds to a second change in a notation of a later phase. For that purpose, the circuits underlying the notations are formally compared. Each notation describes the circuit as a boolean finite automaton, whereby a comparison of two automatons is implemented in that their input variables, output variables and operands are compared to one another. An allocation of operands corresponding to one another is determined on the basis of a status dependency graph, whereby a resolution with operands of the automatons is refined such that, preferably, corresponding allocations of operands of the automatons result. A coarsening method assures that no resolutions arise that make an allocation impossible.

Claims8

Dependent claims

A method for comparison of electrical circuits, comprising:

providing a representation of a first circuit by a first automaton;
providing a representation of a second circuit by a second automaton;
providing an allocation of input variables of the first automaton onto input variables of the second automaton and an allocation of output variables of the first automaton onto output variables of the second automaton;
providing a base set with operands of the first and of the second automaton,
proceeding from a predetermined resolution of the base set, implementing the following steps
(1) determining which data dependencies exist between operands, input variables and output variables for each operand of the resolution, wherein
determining those operands and those input variables on which a status transition function of the operand is dependent, and
determining those operands and those output variables that are dependent on the operand for each operand,
(2) combining those operands that are determined by identical data dependencies according to step (1) in a group of the resolution, and
(3) implementing step (2) for all operands, so that a refinement of the resolution is determined,
whereby operands of the respective group being considered allocated to one another;
and
implementing a comparison of the two circuits underlying the automatons on the basis of the identified allocations.

10 more elements

Dependencies are inferred from the claim text.

Method for the comparison of electrical circuits

Life of this patent

Method for the comparison of electrical circuits

Life of this patent

Abstract

Claims8