A characterized cell library for EDA tools includes receiver model data that provides two or more capacitance values for a given receiver modeling situation (signal type and operating conditions). The receiver model can then use different capacitance values to generate different portions of the model receiver signal, thereby enabling more accurate matching of actual receiver signal timing characteristics. For example, a two-capacitance receiver model can be generated by using the first capacitance value to match the delay characteristics of an actual receiver, and by using the second capacitance (in light of the use of the first capacitance) to match the slew characteristics of that actual receiver. Because typical EDA timing analyses focus mainly on delay and slew (and not the detailed profile of circuit signals), a two-capacitance receiver model can provide a high degree of accuracy without significantly increasing cell library size and computational complexity.

A method for enhancing power bus for I/O libraries in ASIC designs is disclosed. An I/O assignment for I/O circuits to be utilized in an ASIC design is initially generated. Each I/O circuit may obtain power from either a primary I/O power bus or a secondary I/O power bus. A determination is then made as to whether or not the I/O assignment meets certain predetermined power distribution requirements. In a determination that the I/O assignment does not meet the predetermined power bus distribution requirements, a power enhancement cell is added. The power enhancement circuit includes at least one metal line for connecting the primary I/O power bus to the secondary I/O power bus in order for the I/O assignment to meet the power bus distribution requirements.

Wiring structures and methods for integrated circuit designs which are adapted to reduce metal variation effects on launch-capture clock pairs in order to minimize cycle time overlap violations in launch/capture clocking systems are provided, whereby the A/B/C (test/launch/capture) clock wire nets are designed using a five parallel track wire segment, in which the B clock wire is represented as a double track with one metal track and one adjacent isolation/shielding track, the C clock wire is represented as a double track with one metal track and one adjacent isolation/shielding track, and where the A test clock wire is represented as a single track comprising test signal wire disposed between the B and C signal wires.

A technique will automatically route interconnect of an integrated circuit while taking into consideration current density rules. In an implementation, the technique uses a shape-based approach where a grid is not used. Based on data input including current density and a frequency of each net, the technique will determine the current requirements for each net. In an implementation, the technique forms a Steiner tree for a net, and routs using the Steiner tree. The technique widens nets having greater current requirements; adjacent wiring may be pushed aside to create sufficient space for wider nets.

A system of automatically routing interconnect of a integrated circuit design while taking into consideration the parasitic issues of the wiring as it is created. The system will be able to select an appropriate wiring pattern so that signals meet their performance requirements.