Smooth operators in optimization of circuit structures

• US 20040044971A1
• Filed: 08/27/2002
• Published: 03/04/2004
• Est. Priority Date: 08/27/2002
• Status: Active Grant

• Current Assignee: Synopsys Incorporated
• Original Assignee: Synopsys Incorporated
• Inventors: McConaghy, Trent Lorne
• Granted Patent: US 6,859,914 B2
• Time in Patent Office: Days
• US Class Current: 716/2
• CPC Class Codes: G06F 30/36 Circuit design at the analogue level

Abstract

A method of identifying semiconductor design candidates from a population of semiconductor technology designs leverages specialized operators which are smooth in the sense that the operators are capable of producing small changes in the performance or behaviour when applied to a design to modify it. The method includes determining a smooth operator for effecting incremental structural change to a semiconductor technology design when the smooth operator is applied to the semiconductor technology design and then applying the smooth operator to at least one semiconductor technology design in the population to determine an updated population. The semiconductor technology designs in the updated population are evaluated to identify a preferred semiconductor technology design candidate. If the stopping condition is satisfied then the search terminates otherwise the steps are repeated.

Claims

1. A method of identifying preferred semiconductor technology design candidates from a population of semiconductor technology designs, the method comprising:

(a) determining a smooth operator for effecting incremental structural change to a semiconductor technology design when the smooth operator is applied to the semiconductor technology design;

(b) applying the smooth operator to at least one semiconductor technology design in the population to determine an updated population;

(c) evaluating the semiconductor technology designs in the updated population to identify at least one preferred semiconductor technology design candidate; and

(d) determining whether the at least one preferred semiconductor technology design candidate satisfies a stopping condition.

2. The method of claim 1, further comprising repeating steps (b) to (d) until the stopping condition is satisfied.

3. The method of claim 2, wherein the determining whether the at least one preferred semiconductor technology design candidate satisfies a stopping condition comprises comparing the performance value of the at least one preferred semiconductor technology design candidate to a predetermined value, the stopping condition being satisfied if the performance value meets or exceeds the predetermined value.

4. The method of claim 2, wherein the performance value of the at least one preferred semiconductor technology design candidate is the objective function value of the at least one preferred semiconductor technology design candidate, the objective function being a mapping from design space to a corresponding space of objective function values.

5. The method of claim 1, wherein determining a smooth operator for effecting incremental structural change to a semiconductor technology design comprises determining a plurality of smooth operators.

6. The method of claim 1, wherein applying the smooth operator to at least one semiconductor technology design in the population comprises applying a plurality of smooth operators in sequence.

7. The method of claim 2, wherein the stopping condition comprises a resource limitation.

8. The method of claim 4, wherein the resource limitation is a limit to the number of times that steps (b) to (d) are to be repeated.

9. The method of claim 4, wherein the resource limitation is a limitation on the amount of computation time is to be expended.

10. The method of claim 4, wherein the resource limitation is a limitation on the amount of elapsed time permitted.

11. The method of claim 1, wherein the steps (a) to (d) are automated in a search engine.

12. A method of identifying preferred semiconductor technology design candidates from a population of semiconductor technology designs, the method comprising:

initially seeding the population of semiconductor technology designs with at least one seed semiconductor design;

determining a set of operators for application to the population of semiconductor technology designs, each operator transforming a semiconductor technology design to a modified semiconductor technology design when the operator is applied to the semiconductor technology design, the set of operators including at least one smooth operator for effecting incremental structural change to a semiconductor technology design;

applying at least one operator from the set of operators to at least one semiconductor technology design in the population to determine an updated population;

evaluating the semiconductor technology designs in the updated population to identify at least one preferred semiconductor technology design candidate;

determining whether the at least one preferred semiconductor technology design candidate satisfies a stopping condition; and

if the stopping condition is not satisfied, repeatedly further applying operators and evaluating resulting updated populations until the stopping condition is satisfied.

13. In structural optimization of semiconductor technology designs using a search engine, a computer-readable program product for identifying preferred semiconductor technology design candidates from a population of semiconductor technology designs, the program product comprising:

means for initially seeding the population of semiconductor technology designs with at least one seed semiconductor technology design;

means for determining a set of operators for application to the population of semiconductor technology designs, each operator transforming a semiconductor technology design to a modified semiconductor technology design when the operator is applied to the semiconductor technology design, the set of operators including at least one smooth operator for effecting incremental structural change to a semiconductor technology design;

means for applying at least one operator from the set of operators to at least one semiconductor technology design in the population to determine an updated population;

means for evaluating the semiconductor technology designs in the updated population to identify at least one preferred semiconductor technology design candidate; and

means for determining whether the at least one preferred semiconductor technology design candidate satisfies a stopping condition.