摘要:
A method for hierarchical analysis of electronic circuits comprises selecting a first one of a plurality of abstraction levels of a general design model (GDM). The GDM comprises a first design description of electronic circuits at a plurality of abstraction levels and a plurality of foci, organized into sub-blocks. The method selects a first focus of the plurality of foci to select a first sub-block. The method identifies incomplete electronic circuits in the selected first sub-block. The method generates a second design description of the first sub-block to exclude identified incomplete electronic circuits, wherein the second design description is suitable for electronic design analysis (EDA). The method stores the generated second design description for subsequent use. Subsequent iterations thereby include all components of circuits that were incomplete in prior iterations.
摘要:
A method and a system for selecting timing points in an electrical interconnect network to be used in electrical simulations for a static timing analysis for improved accuracy. The present method includes discovering choke points in an electrical model of the interconnect for which all the paths from drivers to receivers must pass through on certain types of nets. The method then uses the choke point electrical nodes, where they exist, as an output timing point of the logic gate driving the net. The method solves the problem of inaccuracies due to resistances between different driver pins on the same interconnect net, though it can also be applied to solving analogous inaccuracies due to resistances between different receiver pins associated with the same receiver timing point. It further also applies to interconnect with other two-port parasitic elements, to cases where only a subset of receiver pins on the net require accurate timing, and to cases where a set of electrical nodes, rather than a single node, partition all paths from drivers to receivers on a net.
摘要:
A method for hierarchical analysis of electronic circuits comprises selecting a first one of a plurality of abstraction levels of a general design model (GDM). The GDM comprises a first design description of electronic circuits at a plurality of abstraction levels and a plurality of foci, organized into sub-blocks. The method selects a first focus of the plurality of foci to select a first sub-block. The method identifies incomplete electronic circuits in the selected first sub-block. The method generates a second design description of the first sub-block to exclude identified incomplete electronic circuits, wherein the second design description is suitable for electronic design analysis (EDA). The method stores the generated second design description for subsequent use. Subsequent iterations thereby include all components of circuits that were incomplete in prior iterations.
摘要:
A method and a system for selecting timing points in an electrical interconnect network to be used in electrical simulations for a static timing analysis for improved accuracy. The present method includes discovering choke points in an electrical model of the interconnect for which all the paths from drivers to receivers must pass through on certain types of nets. The method then uses the choke point electrical nodes, where they exist, as an output timing point of the logic gate driving the net. The method solves the problem of inaccuracies due to resistances between different driver pins on the same interconnect net, though it can also be applied to solving analogous inaccuracies due to resistances between different receiver pins associated with the same receiver timing point. It further also applies to interconnect with other two-port parasitic elements, to cases where only a subset of receiver pins on the net require accurate timing, and to cases where a set of electrical nodes, rather than a single node, partition all paths from drivers to receivers on a net.
摘要:
A method for further reducing RC parasitics in an interconnect network following internal node elimination is described. A resistor is initially selected as a candidate for shorting, and it is established whether the accumulated delay error at either end of the resistor is less than a predetermined threshold. This threshold must be a fraction of the time-constant threshold selected by internal node elimination techniques in order to limit the growth of the accumulated delay errors. An important aspect of the invention is the simplicity of the formula used to change the downstream resistor values, namely, the product of the value of the resistor shorted and the ratio of the cumulative downstream capacitances of the two ends of the resistor whose value is being changed. This particular choice of updating the downstream resistor values minimizes the absolute-value of the delay errors at every node due to shorting of the selected resistor. It also preserves the delays at all nodes in the interconnect network apart from the two ends of the resistor selected for shorting.