Abstract: A system for estimating stage delay in an integrated circuit design includes steps of receiving as input an integrated circuit design including a single stage having at least two inputs, an output, and an interconnect connected to the output; calculating a separate interconnect delay for the interconnect as a function of an input ramptime for each of the inputs; adding a gate delay of each of the inputs to the separate interconnect delay calculated as a function of the input ramptime to estimate a stage delay for each of the inputs; and generating as output the stage delay for each of the inputs.

Abstract: A method for determining a timing margin to be applied in an integrated circuit timing design. Circuit simulator path delays and static timing analysis tool path delays are determined for the integrated circuit timing design. The circuit simulator path delays are plotted in a first plot versus a percentage difference between the circuit simulator path delays and the static timing analysis tool path delays, and in a second plot are plotted versus a numerical difference between the circuit simulator path delays and the static timing analysis tool path delays. A first point is identified on the second plot having a largest numerical difference, and the circuit simulator path delay for the first point is identified. A corresponding point on the first plot having the circuit simulator path delay is found, and the percentage difference for the corresponding point is identified. A combination of both the circuit simulator path delay and the percentage difference is used as the timing margin.

Abstract: A system, apparatus and method for generating and validating extracted timing model files, such as macro library files, are disclosed. A user interface or data template is provided to an engineer that allows for the population of data within particular fields related to timing characteristics of an IP block, cell or core. An extracted timing model file is generated and a validation procedure is performed. This validation procedure may include comparing the information with the file to a test bench have a plurality of test points. In particular, data provided by the engineer is checked against multiple criteria to ensure that this data is valid and/or falls within an appropriate value range constraints. After the validation procedure has completed, the engineer is provided a summary of the validation results.

Abstract: A method of computing output delay in a mathematical model of an integrated circuit by sorting cells of original design of an the integrated circuit in a topological order. The original output delays for the sorted cells in the original design are computed in the topological order, to produce original output ramp times. The original output ramp times are propagated and original output delays are computed, and the original output ramp time and original output load for each cell is stored. The cells of the original design are modified to produce a modified design. For each modified cell in the topological order, a new output delay and a new output ramp time are computed and compared to the original output ramp time on the modified cell. When the new output ramp time substantially equals the original output ramp time for a modified cell, the calculations of the modified output ramp time for cells that are further down in the topological order are stopped.

Abstract: A system, apparatus and method for generating extracted timing model files, such as macro library files, are disclosed. A user interface or data template is provided to an engineer that allows for the population of data within particular fields related to timing characteristics of an IP block, cell or core. Various types of data and fields may be provided into the user interface or data template. The location of relevant files, such as a cell or core netlist, may be provided within the template. Additionally, one or more modes may be selected by the user to define the manner in which the ETM file(s) are to be generated. An ETM file is automatically generated using the information provided in the data template.

Abstract: A system for estimating stage delay in an integrated circuit design includes steps of receiving as input an integrated circuit design including a single stage having at least two inputs, an output, and an interconnect connected to the output; calculating a separate interconnect delay for the interconnect as a function of an input ramptime for each of the inputs; adding a gate delay of each of the inputs to the separate interconnect delay calculated as a function of the input ramptime to estimate a stage delay for each of the inputs; and generating as output the stage delay for each of the inputs.

Abstract: A method for accounting for negative bias temperature instability in a rise delay of a circuit design, the method comprising the steps of create a cell and net model library with original rise numbers, construct the circuit design from the cell and net models, for each cell and net in the circuit design, calculate an original rise delay, apply a negative bias temperature instability model to determine a parameter shift, determine a new rise number from the parameter shift, and calculate a new rise delay by original rise delay* (original rise number)/(new rise number).

Abstract: A method of computing output delay in a mathematical model of an integrated circuit original design by sorting cells of the original design in a topological order. The original output delays for the cells in the original design are computed in the sorted order, to produce original output ramp times. The original output ramp times are propagated and original output delays are computed, and the original output ramp time and original output load for each cell is stored. The cells of the original design are modified to produce a modified design. For each modified cell in the topological order, a new output delay and a new output ramp time are computed and compared to the original output ramp time on the modified cell. When the new output ramp time substantially equals the original output ramp time for a modified cell, the calculations of the modified output ramp time for cells that are further down in the topological order are stopped.

Abstract: An improved method for interconnect delay analysis for VLSI circuits reduces a parasitic graph for moment computation by eliminating one or more nodes in the graph the elimination process is performed based upon the degree of the nodes. By eliminating nodes in this fashion, the computation complexity is significantly reduced. With this elimination process, resistor loops and crossed loops can also be solved. The order in which the nodes are eliminated is optimized using the depth-first-search method on the parasitic graphs, further reducing the computation complexity. The method provides a consistent functional interface, applicable to different circuit model structures. In addition, the method accounts for coupling capacitance between interconnects.

Abstract: A method of determining whether voltage from an aggressor net exceeds a voltage threshold on a victim net design in an integrated circuit design. Probabilistic noise from the aggressor net on the victim net is calculated. The probabilistic noise is checked against the voltage threshold, and the victim net design is passed when the probabilistic noise does not exceed the voltage threshold. When the probabilistic noise does exceed the threshold, then an effective noise at a desired mean time to failure is computed, and the effective noise is checked against the voltage threshold. The victim net design is passed when the effective noise does not exceed the voltage threshold, and failed when the effective noise does exceed the threshold.

Abstract: A method for accounting for negative bias temperature instability in a rise delay of a circuit design, the method comprising the steps of create a cell and net model library with original rise numbers, construct the circuit design from the cell and net models, for each cell and net in the circuit design, calculate an original rise delay, apply a negative bias temperature instability model to determine a parameter shift, determine a new rise number from the parameter shift, and calculate a new rise delay by original rise delay*(original rise number)/(new rise number).

Abstract: A method for determining a timing margin to be applied in an integrated circuit timing design. Circuit simulator path delays and static timing analysis tool path delays are determined for the integrated circuit timing design. The circuit simulator path delays are plotted in a first plot versus a percentage difference between the circuit simulator path delays and the static timing analysis tool path delays, and in a second plot are plotted versus a numerical difference between the circuit simulator path delays and the static timing analysis tool path delays. A first point is identified on the second plot having a largest numerical difference, and the circuit simulator path delay for the first point is identified. A corresponding point on the first plot having the circuit simulator path delay is found, and the percentage difference for the corresponding point is identified. A combination of both the circuit simulator path delay and the percentage difference is used as the timing margin.

Abstract: An improved method for interconnect delay analysis for VLSI circuits reduces a parasitic graph for moment computation by eliminating one or more nodes in the graph. The elimination process is performed based upon the degree of the nodes. By eliminating nodes in this fashion, the computation complexity is significantly reduced. With this elimination process, resistor loops and crossed loops can also be solved. The order in which the nodes are eliminated is optimized using the depth-first-search method on the parasitic graphs, further reducing the computation complexity. The method provides a consistent functional interface, applicable to different circuit model structures. In addition, the method accounts for coupling capacitance between interconnects.

Abstract: In exemplary embodiments, a method and computer program product for predicting quiescent current variation of an integrated circuit die include steps of: (a) receiving as input a value of a derating factor from a process monitor cell on an integrated circuit die and an on-chip variation of the derating factor; (b) constructing a curve fitting formula for estimating a quiescent current of the integrated circuit die as a function of the derating factor; (c) calculating minimum and maximum values of the quiescent current from the curve fitting formula, the value of the derating factor from the process monitor cell, and the on-chip variation of the derating factor to generate an estimate of minimum and maximum values for the quiescent current; and (d) generating as output the estimated minimum and maximum values of the quiescent current.

Abstract: In exemplary embodiments, a method and computer program product for predicting quiescent current variation of an integrated circuit die include steps of: (a) receiving as input a value of a derating factor from a process monitor cell on an integrated circuit die and an on-chip variation of the derating factor; (b) constructing a curve fitting formula for estimating a quiescent current of the integrated circuit die as a function of the derating factor; (c) calculating minimum and maximum values of the quiescent current from the curve fitting formula, the value of the derating factor from the process monitor cell, and the on-chip variation of the derating factor to generate an estimate of minimum and maximum values for the quiescent current; and (d) generating as output the estimated minimum and maximum values of the quiescent current.

Abstract: A method includes steps of: (a) receiving as input a waveform of a transient signal as a function of time for an aggressor net; (b) finding a peak value of the waveform and a corresponding peak time of the waveform propagated from the aggressor net to a victim net; (c) defining a selected time interval within the waveform at the victim net that includes the peak value and excludes features of the waveform not associated with the peak value wherein the selected time interval begins at a first time and ends at a second time; (d) calculating a weighted value of a function of the waveform at the first time and the second time; (e) calculating a local average value of the waveform as a function of the peak value and the weighted value; and (f) generating as output the local average value of the waveform.

Abstract: A method includes steps of: (a) receiving as input a waveform of a transient signal as a function of time for an aggressor net; (b) finding a peak value of the waveform and a corresponding peak time of the waveform propagated from the aggressor net to a victim net; (c) defining a selected time interval within the waveform at the victim net that includes the peak value and excludes features of the waveform not associated with the peak value wherein the selected time interval begins at a first time and ends at a second time; (d) calculating a weighted value of a function of the waveform at the first time and the second time; (e) calculating a local average value of the waveform as a function of the peak value and the weighted value; and (f) generating as output the local average value of the waveform.

Abstract: A method of calculating delay for a process variation includes finding a value for each of exactly two independent variables that results in a maximum or minimum variation of estimated cell delay plus net delay, calculating a variation of resistance from the value found for each of the exactly two independent variables, calculating a variation of capacitance from the value found for each of the exactly two independent variables, adding the calculated variation of resistance to a net resistance to generate a modified net resistance for a selected net, adding the calculated variation of capacitance to a net capacitance to generate a modified net capacitance for the selected net, and calculating the cell delay plus net delay from the modified net resistance and the modified net capacitance.

Abstract: A method for modeling the output waveform of a cell driving a resistance-capacitance network includes multiple effective capacitances. A method of calculating Thevenin parameters includes the steps of (a) initializing estimates of effective capacitances Ceff1 and Ceff2, of a switching threshold delay t0, and of a slope delay deltat; (b) solving ramp response equations for t0 and deltat as a function of Ceff1 and Ceff2; (c) comparing the estimates of t0 and deltat with solutions for t0 and deltat found in step (b); and (d) replacing the estimates of t0 and deltat with the solutions for t0 and deltat if the solutions for t0 and deltat have not converged to the estimates of t0 and deltat.

Abstract: Methods for calculating delays for cells in ASICs are disclosed. In the present invention, delays are computed by considering not only the process (P), voltage (V), temperature (T) but also input ramptime (R) and output load or fanout (F) of the cells by fitting the delay at four corner points for derated PVT condition into a non-linear equation which is a function of P, V, T, R and F. Thus, the delay is a five dimensional characterization, and the characterization is split into (P,V,T) characterization and (R,T) characterization to reduce the characterization time and resources. The present invention provides for accurate calculation of delays for cells in ASICs.