Patent ID: 6651224
Filing Date: 2003-11-18
Classification: G06F

Abstract:
A method of optimizing signal distribution through signal lines which connect a signal supplying source to a plurality of elements which are supplied with a signal from the signal supplying source through the signal lines, the method being utilized when designing a circuit including the signal supplying source and the plurality of elements, the method of optimizing the signal lines within the circuit comprising:determining whether or not the signal supplying source satisfies a fan-out restriction if the signal supplying source supplies a signal to all of the driven elements which are directly connected to the signal supplying source; dividing the plurality of elements into a plural number of groups so that the fan-out restriction is satisfied in each of the groups and that each of the groups has the same or substantially the same load capacity, when it is determined that the signal supplying source does not satisfy the fan-out restriction; and inserting, into each of the divided groups, a buffer element having a size which makes the groups of elements satisfy the fan-out restriction; wherein the inserted buffer element is regarded as a driven element, and then it is again determined whether or not the signal supplying source satisfies the fan-out restriction if the signal supplying source supplies a signal to all of the driven elements which are directly connected to the signal supplying source, and the dividing and the inserting are repeatedly carried out until the determining delivers a determination that the signal supplying source satisfies the fan-out restriction, where the determining delivers a determination that the signal supplying source does not satisfy the fan-out restriction, then an evaluation value calculation is carried out in such a manner that an evaluation value is calculated for each of the all pairs of the driven elements on the basis of a circuit performance enhancing factor, and the driven elements are divided into groups so that, of pairs satisfying the fan-out restriction, a pair having the largest evaluation value calculated at the evaluation calculation is made to belong to the same group with priority.