Abstract: In accordance with the present invention, a method, system, computer system, and computer program product for considering clock skew in designing digital systems with latch-controlled circuits are provided. The disclosure teaches a method for determining whether logic operations can be performed within the available time and allows detailed modeling of clock skew for different domains of the integrated circuit. Taking clock skew into account for each domain, worst-case timing paths can be determined for circuits controlled by either flip-flops or latches. A design of an integrated circuit can be revised or verified using the method taught. The disclosure envisions that integrated circuits, printed circuit boards, computer systems and other components will be manufactured based upon designs developed with the method taught.

Abstract: In accordance with the present invention, a method, system, computer system, and computer program product for considering clock skew in designing digital systems with latch-controlled circuits are provided. The disclosure teaches a method for determining whether logic operations can be performed within the available time and allows detailed modeling of clock skew for different domains of the integrated circuit. Taking clock skew into account for each domain, worst-case timing paths can be determined for circuits controlled by either flip-flops or latches. A design of an integrated circuit can be revised or verified using the method taught. The disclosure envisions that integrated circuits, printed circuit boards, computer systems and other components will be manufactured based upon designs developed with the method taught.

Abstract: A data processing system which calculates timing delays in a circuit having a switching device (3). A computer processor (22) receives input describing a circuit and calculates the timing delays for each switching device (3) or stage. To perform each calculation the computer processor (22) models the circuit incorporating effective resistance R.sub.eff (24), Miller capacitance C.sub..mu. (7), and an associated Miller coefficient. The Miller coefficient is a defined by the behaviour of the model. The model is then reduced to a set of equations, the variables are determined, and the timing delay calculated. In one embodiment, successive stages are calculated to locate timing violations in circuit design. In alternate embodiments, models such as CRYSTAL (4) or the Sakurai model are enhanced by Miller capacitance considerations, however many other models may be used.

Abstract: A process and implementing computer system (13) for optimally sizing elements of an integrated circuit includes determining actual arrival times and required arrival times (403) for processed signals at all nodes within the integrated circuit and determining the slack or difference (405) between arrival and required times for each node. If the actual arrival time for a particular node is after the time required to meet a predetermined design constraint of the node (407), a determination (411) is made regarding the effect of that element on the nodal slack for an incremental increase in the size of that element. Thereafter an element is selected (413) for sizing increase (415) in accordance with a weighting function and the process is repeated until all of the nodes in the integrated circuit have positive slack times (407, 409).