International Business Machines Corporation

Mark R Lasher

Daniel Richard Menard

Peter Anton Habitz

William John Livingstone

Eric A Foreman

Gregory M Schaeffer

Laura R Darden

Phillip P Normand, Ii

Keith M Carrig

Philip P Normand

Geetha Arthanari

A method, system and computer program product for implementing enhanced clock tree distributions to decouple across N-level hierarchical entities of an integrated circuit chip. Local clock tree distributions are constructed. Top clock tree distributions are constructed. Then constructing and routing a top clock tree is provided. The local clock tree distributions and the top clock tree distributions are independently constructed, each using an equivalent local clock distribution of high performance buffers to balance the clock block regions.

Implementing enhanced clock tree distributions to decouple across N-level hierarchical entities

A method of estimating an inductance delay includes determining a resistance-capacitance (RC) delay with resistances and capacitances of a network and estimating an inductance delay of the network by determining a propagation delay of an electromagnetic (EM) field across wires of the network. Additionally, the method includes determining if the RC delay is below a specified threshold and adding the estimated inductance delay to the RC delay to determine a total time to propagate voltage swings through the network if the RC delay is below the specified threshold.

Method to quickly estimate inductance for timing models

Forming of a statistical model for a set of independently variable parameters for analysis of a circuit design is disclosed. In one embodiment, a method includes establishing a timing model including delay and delay changes due to process parameter variations (Pi) that impact timing; selecting an element of the circuit design that dominates circuit delay in the timing model; determining a delay sensitivity of each of a set of derived process parameters (Vj) for the element that are linear combinations of the process parameter variations (Pi); and selecting only those derived process parameters with a high sensitivity for use in the statistical model. The invention simplifies the statistical model and reduces the number of calculations require for timing analysis. A method of performing a timing analysis using the simplified statistical model is also disclosed.

Forming statistical model of independently variable parameters for timing analysis

A method of designing a clock tree in an integrated circuit combines steps of making a list of all clock sinks; positioning a temporary reference insertion point (TIP); grouping the sinks together with structured clock buffers (SCBs) in a set of levels; and moving the SCBs to improve symmetry of the tree. The SCBs may be of several sizes and may be positioned horizontally or vertically and moved within limits to permit the program to calculate a complete tree.

ASIC clock floor planning method and structure

A method, system and program product are disclosed that create new shapes at detected shape overlaps and includes those new shapes during routing and net checking when the new shapes require a larger space than any of the overlapping shapes. The invention thus detects and prevents spacing errors without the expense of time consuming design rule checking (DRC), facilitating early detection and prevention of errors.

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Colchester, VT, United States of America

Mark R Lasher