Adaptive power control based on pre package characterization of integrated circuits

• US 20040128090A1
• Filed: 12/31/2002
• Published: 07/01/2004
• Est. Priority Date: 12/31/2002
• Status: Active Grant

• Current Assignee: Meta Platforms, Inc. (f/k/a Facebook, Inc.)
• Original Assignee: Transmeta Corporation (Novafora, Inc.)
• Inventors: Read, Andrew, Wing, Malcolm
• Granted Patent: US 7,228,242 B2
• Time in Patent Office: Days
• US Class Current: 702/75
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/324 by lowering clock frequency
• CPC Class Codes: G06F 1/3296 by lowering the supply or operating voltage
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A method and system of adaptive power control based on pre package characterization of integrated circuits. Characteristics of a specific integrated circuit are used to adaptively control power of the integrated circuit.

Claims

1. A method of operating a microprocessor comprising:

determining a desirable operating frequency for said microprocessor;

accessing information stored within and specific to said microprocessor, said information used to determine an optimal voltage for operating said microprocessor at said desirable operating frequency, said optimal voltage based upon characteristics of said microprocessor; and

operating said microprocessor at said optimal voltage.

2. The method of claim 1 wherein said information is encoded within said microprocessor prior to packaging of said microprocessor.

3. The method as described in claim 1 further comprising operating said microprocessor at said desirable operating frequency while operating at said optimal voltage.

4. The method as described in claim 1 wherein said characteristics of said microprocessor comprise a temperature measurement of said microprocessor.

5. The method as described in claim 4 wherein said temperature measurement is made proximate to said accessing.

6. The method as described in claim 1 wherein said information comprises a mapping into one of a plurality of sets of frequency-voltage operating points.

7. The method as described in claim 6 wherein said plurality of sets of frequency-voltage operating points are not stored in said microprocessor.

8. A method of manufacturing a microprocessor comprising:

accessing a plurality of unpackaged microprocessors;

determining a voltage required by one microprocessor of said plurality of unpackaged microprocessors to meet a power limit at a specified frequency; and

encoding information of said voltage into said one microprocessor.

9. The method as described in claim 8 wherein said determining is performed prior to packaging said one microprocessor.

10. The method as described in claim 9 wherein said determining is performed at a wafer level.

11. The method as described in claim 10 wherein said encoding is also performed at said wafer level.

12. The method as described in claim 8 wherein said voltage is determined by measuring capacitance of said one microprocessor.

13. The method as described in claim 8 wherein said voltage is determined by measuring idle current of said one microprocessor.

14. The method as described in claim 8 wherein said determining is performed at more than one temperature.

15. The method as described in claim 8 wherein said information comprises a mapping into one of a plurality of frequency-voltage characteristic relationships.

16. An integrated circuit comprising:

microprocessor circuitry;

at least one bit of non-volatile storage coupled to said microprocessor circuitry; and

wherein said non-volatile storage comprises information of frequency-voltage characteristics of said integrated circuit.

17. The integrated circuit as described in claim 16 wherein said information comprises a mapping into one of a plurality of frequency-voltage characteristic groups.

18. The integrated circuit as described in claim 16 wherein said microprocessor circuitry provides values indicative of operating conditions of said integrated circuit.

19. The integrated circuit as described in claim 18 wherein said values comprise a temperature of said integrated circuit.

20. The integrated circuit as described in claim 18 wherein said values comprise a desired operating frequency of said integrated circuit.

21. The integrated circuit as described in claim 16 wherein said at least one bit of non-volatile storage is non-resetable.

22. The integrated circuit as described in claim 16 wherein said information is stored prior to packaging of said integrated circuit.

23. A data structure in computer readable memory comprising:

two sets of frequency-voltage operating points wherein;

each frequency-voltage operating point of said sets specifies a minimum operating voltage required for a microprocessor integrated circuit to operate at a desired frequency; and

wherein further

each set of frequency-voltage operating points represents a class of microprocessor integrated circuits, each of said class of microprocessor integrated circuits having differing frequency-voltage characteristics.

24. The data structure as described in claim 23 wherein said data structure external to a microprocessor integrated circuit.

25. The data structure as described in claim 23 further comprising temperature-dependent operating voltage information.

26. The data structure as described in claim 23 wherein each of said sets of frequency-voltage operating points is indexable by information stored in a microprocessor integrated circuit.

27. A computer comprising:

a microprocessor integrated circuit;

a voltage supply coupled to said microprocessor integrated circuit for furnishing a selectable voltage to said microprocessor integrated circuit;

a memory space coupled to said microprocessor integrated circuit comprising instructions to implement a method of optimizing an operating voltage of said microprocessor integrated circuit, said method comprising;

determining a desirable operating frequency for said microprocessor integrated circuit;

accessing information stored within said microprocessor integrated circuit to determine an optimal voltage for operating said microprocessor at said desirable operating frequency, said optimal voltage based upon characteristics of said microprocessor integrated circuit; and

causing said voltage supply to furnish said optimal voltage to said microprocessor integrated circuit.

28. The computer as described in claim 27 further comprising a second memory space comprising at least two sets of frequency-voltage operating points wherein:

each frequency-voltage operating point of said sets specifies a minimum operating voltage required for a microprocessor integrated circuit to operate at a desired frequency; and

wherein further each set of frequency-voltage operating points represents a class of microprocessor integrated circuits, each class of microprocessor integrated circuits having differing frequency-voltage characteristics.

29. The computer as described in claim 28 wherein said information comprises a mapping into one of said sets of frequency-voltage operating points.

30. The computer as described in claim 28 wherein said second memory space is not contained within said microprocessor integrated circuit.

31. The computer as described in claim 28 wherein said second memory space further comprises temperature-dependent operating voltage information.

32. The computer as described in claim 31 further comprising means to measure a temperature of said microprocessor integrated circuit.

33. The computer as described in claim 32 wherein said method further comprises:

accessing a temperature of said microprocessor integrated circuit; and

accessing said temperature-dependent operating voltage information to determine an optimal voltage for operating said microprocessor at said desirable operating frequency and said temperature of said microprocessor integrated circuit.

34. An electronic device comprising:

a memory storing a plurality of voltage-frequency relationships related to a class of microprocessors; and

a microprocessor, of said class of microprocessors, wherein said microprocessor comprises an information stored thereon indicating a particular voltage-frequency relationship of said plurality of voltage-frequency relationships wherein said particular voltage-frequency relationship is specific to said microprocessor and used to select an optimum voltage to be applied to said microprocessor based on a desired frequency of operation of said microprocessor.

35. A device as described in claim 34 and further comprising logic for applying said optimum voltage and for causing said microprocessor to operate at said desired frequency of operation, said logic coupled to said memory and coupled to said microprocessor.

36. A device as described in claim 34 wherein said memory is separate from said microprocessor.

37. A device as described in claim 34 wherein said information is stored in a programmable fuse integrated on said microprocessor.

38. A device as described in claim 34 wherein said information is stored in a programmable memory integrated on said microprocessor.

39. A device as described in claim 34 wherein said information is obtained after characterization of said microprocessor.

40. A device as described in claim 39 wherein said information is programmed into said microprocessor at wafer level.