1. A method for predicting simultaneous switching output noise of an integrated circuit device, comprising:
obtaining, by a computer, user input including:
an identification of an inputoutput bank of an integrated circuit die;
an identification of a device package substrate to which the integrated circuit die is to be attached; and
an identification of inputoutput interface to be used by the inputoutput bank;
selecting a noise factor and an impedance responsive to the user input;
multiplying the noise factor with the impedance to provide a result; and
outputting the result as a prediction of the simultaneous switching output noise of the integrated circuit device.
2. The method according to claim 1, wherein the user input further includes a frequency of operation.
3. The method according to claim 2, wherein the inputoutput interface is selected from inputoutput standard interfaces.
4. The method according to claim 3, wherein the user input further includes a number of aggressors.
5. A method for predicting simultaneous switching output noise of an integrated circuit device, comprising:
computing a plurality of impedance profiles as a function of frequency responsive to simulated stimulus provided to a system model,
wherein the plurality impedance profiles are for a plurality of inputoutput banks of a plurality of integrated circuit devices that include the integrated circuit device;
generating through measurement at least one excursion profile for at least one reference inputoutput bank of at least one reference die for at least one device package substrates type;
identifying a resonant frequency from the at least one excursion profile;
generating at least one base noise curve at the resonant frequency for at least one inputoutput interface using multiple quantities of aggressors;
dividing the at least one base noise curve with impedance from an impedance profile of the plurality of impedance profiles for the at least one inputoutput reference bank for the at least one device package substrate type to provide noise factors;
storing the noise factors according to the at least one inputoutput interface and the numbers of aggressors in a database;
storing the plurality of impedance profiles in the database; and
outputting a value for the predicted simultaneous switching output noise of the integrated circuit device by a prediction engine.
6. The method according to claim 5, wherein the prediction engine is configured to:
access the database to obtain a noise factor from the noise factors and an impedance from an impedance profile of the plurality of impedance profiles responsive to user input; and
multiply the noise factor by the impedance using a general-purpose processor to provide the value; and
wherein the computing the plurality of impedance profiles include:
obtaining a structural representation for a device package substrate of the at least one device package substrate type;
determining a substrate model from the structural representation;
integrating the substrate model into the system model in a simulation environment; and
providing as the stimulus a sinusoidal signal to at least one port of the system model to obtain the impedance profile through simulation.
7. The method according to claim 6, further comprising:
obtaining at least one manufacturing database file for the device package substrate; and
determining the structures using manufacturing information in the manufacturing database file,
wherein the manufacturing information includes three-dimensional representations of the structures and materials to be used for the structures.
8. The method according to claim 5, wherein:
the substrate model is a scattering parameter model configured to provide a behavior responsive to frequency of at least one circuitry network associated with the at least one inputoutput reference bank; and
the integrated circuit device includes the device package substrate and an integrated circuit die.
9. The method according to claim 8, wherein the at least one circuitry network includes a power system associated with the at least one inputoutput reference bank.
10. The method according to claim 8, wherein:
the scattering parameter model is a three port scattering parameter model in a format including lists of frequencies, magnitudes, and phases.
11. A non-transitory machine-readable medium having stored thereon information that, when executed by a general-purpose processor, cause performance of a method for predicting simultaneous switching output noise of an integrated circuit device, the method comprising:
obtaining user input including:
an identification of an inputoutput bank of an integrated circuit die;
an identification of a device package substrate to which the integrated circuit die is to be coupled;
an identification of inputoutput interface to be used by a plurality of inputoutput banks; and
a quantity of aggressors;
selecting a noise factor and an impedance responsive to the user input;
multiplying the noise factor with the impedance to provide a result; and
outputting the result as a prediction of the simultaneous switching output noise of the integrated circuit device.
12. The medium according to claim 11, wherein the user input further includes a frequency of operation.
13. The medium according to claim 12, wherein the inputoutput interface is selected from inputoutput standard interfaces.
14. The medium according to claim 13, wherein the user input further includes a number of aggressors.
15. The medium according to claim 14, wherein the method further comprises:
computing a plurality of impedance profiles as a function of frequency responsive to simulated stimulus provided to a system model;
wherein the plurality of impedance profiles are for the plurality of inputoutput banks of a plurality of integrated circuit devices that includes the integrated circuit device;
generating at least one excursion profile for at least one reference bank of at least one reference die for at least one device package substrates type;
identifying a resonant frequency from the at least one excursion profile;
generating at least one base noise curve at the resonant frequency for at least one inputoutput protocol using numbers of aggressors;
dividing the at least one base noise curve using impedance information in the plurality of impedance profiles for the at least one reference bank for the at least one device package substrate type to provide noise factors including the noise factor;
storing the noise factors according to the at least one inputoutput protocol and the numbers of aggressors in a database;
storing the plurality of impedance profiles in the database; and
outputting the result for the predicted simultaneous switching output noise of the integrated circuit device from a prediction engine;
wherein the prediction engine is configured to:
access the database to obtain the noise factor from the noise factors and the impedance from a particular impedance profile of the plurality of impedance profiles responsive to user input; and
multiply the noise factor by the impedance using the general-purpose processor.
16. The medium according to claim 15, wherein the computing the plurality of impedance profiles include:
obtaining a structural representation for a carrier substrate associated with the at least one device package substrate type;
determining a substrate model from the structural representation;
simulating the substrate model in the system model;
integrating the substrate model into the system model in a simulation environment; and
providing as the stimulus a sinusoidal signal to at least one port of the system model to obtain the particular impedance profile through simulation.
17. The medium according to claim 16, wherein the method further comprises:
obtaining at least one manufacturing database file for the carrier substrate;
determining the structures using manufacturing information in the manufacturing database file; and
the manufacturing information including three-dimensional representations of the structures and materials to be used for the structures.
18. The medium according to claim 15, wherein:
the substrate model is a scattering parameter model configured to provide a behavior responsive to frequency of at least one circuitry network associated with the at least one inputoutput reference bank.
19. The medium according to claim 18, wherein the at least one circuitry network includes a power system associated with the at least one reference bank.
20. The medium according to claim 15, wherein:
the database has stored therein the plurality of impedance profiles generated by simulation for all of the plurality of inputoutput banks of all carrier substrates of all die of a family of FPGAs; and
the database further has stored therein noise factors for all inputoutput protocols for multiple quantities of aggressors for all reference banks of all device package substrate types associated with the family of FPGAs.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of controlling a process comprising the steps of:
a) generating a first-principle model corresponding to the process;
b) inputting data describing the current and desired future process conditions;
c) generating a linear approximation to the model which is valid for said current conditions;
d) using said linear approximation to determine an approximate solution to a control problem related to the process; and
e) controlling the process using said approximate solution.
2. A method as claimed in claim 1, wherein the model is non-linear.
3. A method as claimed in claim 1 or 2, wherein the linear approximation is generated by numerical perturbation of the model.
4. A method as claimed in claim 3, wherein the linear approximation provides a quadratic programming problem which is solved to determine the approximate solution to the control problem.
5. A method as claimed in any preceding claim wherein the approximate solution thereby determined is used to determine a more precise solution.
6. A method as claimed in any preceding claim wherein the first-principle model is used to calculate a control response.
7. A method as claimed in any preceding claim wherein the generation of linear approximation to the model is repeated as required using new input data.
8. A method as claimed in any preceding claim wherein the process is a polymerisation process.
9. A method as claimed in claim 8 wherein the process comprises a transition from the production of a first grade of polymer to a second grade of polymer, the transition being controlled automatically.
10. A control apparatus for controlling a process comprising a controller, input and output means and a model, wherein:
a) said model is a fundamental model corresponding to the process;
b) means is provided for inputting data describing the current and desired future process conditions;
c) means is provided for calculating a linear approximation to the model which is valid for said input conditions;
d) means is provided for using said linear approximation to determine an approximate solution to a control problem related to the process;
e) means is provided to generate output signals for controlling the process using the solution of part (d) above.