Abstract: A method in a data processing system for identifying a circuit. In a preferred embodiment, a set of bits, with a defined chain length, are shifted into the circuit one bit at a time. The bits shifted out from the circuit are compared to the bits, from the set of bits, shifted into the circuit to determine if the circuit corresponds to a first type circuit. The comparing step is accomplished before all bits in the set of bits have been shifted into the circuit. If the circuit is not a first type circuit corresponding to the set of bits shifted into the circuit, then the shifting of bits into the circuit is discontinued and the process is repeated with a second set of bits corresponding to a second circuit type until the circuit type has been identified.

Abstract: A method for designing a decoupling circuit for a source line of a LSI includes the steps of determining the capacitance of the decoupling capacitor based on the electric charge necessary for one cycle operation of the LSI and the allowable fluctuation of the source voltage, and determining the inductance of the source line based on the impedance of the decoupling capacitor and the allowable minimum multiplexing ratio of the source current by the decoupling capacitor.

Abstract: Provided are systems and techniques for optimizing an integrated circuit design, in which a critical zone is identified in an integrated circuit design and a plurality of alternative identities are applied in the critical zone in order to obtain a corresponding plurality of outcomes. Alternative representations are then identified as those of the plurality of outcomes pursuant to which at least one of ramptime and timing are improved, and a best one of the alternative representations is selected to replace into the critical zone based on specified priorities which include: (i) selecting based on reduction in ramptime violation; (ii) selecting from among alternative representations that preserve cell area based on timing improvement; and (iii) if all alternative representations increase cell area, selecting based on an evaluation of a relationship between timing decrement and area increment.

Abstract: The present invention selects parts of an integrated circuit description for resynthesis and then prepares those parts for resynthesis. Initially, a resynthesis goal is input, with the resynthesis goal having been selected from a set of possible resynthesis goals. Plural buffer and/or logic trees in the integrated circuit description are then selected based on the resynthesis goal, and information for each of the selected trees is obtained and stored. The tree information includes: (i) a description of each tree cell, including cell types, cell coordinates, and flips and angles of the tree cell, (ii) a description of each input net, (iii) a signal arrival time for each input net as a function of a capacity of such input net, (iv) coordinates of each pin driving each input net, and (v) a maximum capacity of each input net that will prevent such input net from having a timing violation.

Abstract: A method and apparatus for building an integrated circuit. A description of the logical operation of a module in a hardware description language is provided, which includes annotations in the form of design directives. An interpreting process is configured to read the annotations and identify which logical and physical design tools are needed to process each module in the description, as well as the order in which to invoke the logical physical design tools. Dependencies in the execution of the design tools on the various modules of the description are analyzed to determine where the processing of modules may be performed in parallel to optimize execution.

Abstract: A method and apparatus for rendering an integrated circuit design layout is described. Graphics files are generated for selected zoom-in factors from cell-based information of the integrated circuit design, and stored in memory. When a computer operator selects a zoom-in factor greater by a predetermined amount than the largest of such selected zoom-in factors, a selector enables a rendering engine to render the integrated circuit design layout from the cell-based information. On the other hand, when the computer operator selects a zoom-in factor less than the largest of such selected zoom-in factors plus the predetermined amount, the selector enables a graphics processor to render the integrated circuit design layout from appropriate ones of the graphics files.

Abstract: A method for constructing a latch mapping between a first level description and a second level description of a digital system, wherein the first level description and the second level descriptions identify components in the digital system using a predefined naming convention, is provided. The method includes identifying first latch components in the first level description and, for each identified first latch component, storing a first string comprising a selected property of the first latch component in a first storage. The method further includes identifying second latch components in the second level description and, for each second latch component, storing a second string comprising a selected property of the second latch component in a second storage. The method further includes generating a latch mapping by matching the first strings in the first storage with the second strings in the second storage.

Abstract: A method for partitioning wiring connecting individual physical elements of a VLSI chip of a hierarchical design having multiple levels, begins by defining a size for the chip of a hierarchical design, and then removing blocked areas, including clock and power grid areas leaving the wiring channels available for interconnecting the individual elements of the VLSI chip. A percentage of the available area is allocated for wiring levels for global and local wiring as parallel iterations for the global and local wiring proceed and modified as the parallel iterations for the global and local wiring progress. During the parallel iterative process the number of wires increases for the power grid area to prevent a signal wire from having an active wire on either side of the signal wire. In the interactive process, a vertical slice of wiring resources used for the space above a macro entity is defined and the macro entity is checked with the context of the VLSI chip physical design above it.