Temperature Compensation Via Power Supply Modification to Produce a Temperature-Independent Delay in an Integrated Circuit

• US 20120146695A1
• Filed: 02/08/2012
• Published: 06/14/2012
• Est. Priority Date: 02/08/2006
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Zimlich, David
• Granted Patent: US 8,395,436 B2
• Time in Patent Office: Days
• US Class Current: 327/158
• CPC Class Codes: H03L 1/022 by indirect stabilisation, i.e. by generating an electrical correction signal which is a function of the temperature H03L1/021 takes precedence
• CPC Class Codes: H03L 7/0814 the phase shifting device being digitally controlled

Abstract

A method and circuitry for adjusting the delay of a variable delay line (VDL) in a delay locked loop (DLL) or other delay element or subcircuit on an integrated circuit is disclosed. Such delay circuitry will inherently have a delay which is a function of temperature. Such temperature-dependent delays are compensated for by adjusting the power supply voltage of the VDL, delay element, or subcircuit. Specifically, a temperature sensing stage is used to sense the temperature of the integrated circuit. Information concerning the sensed temperature is sent to a regulator which derives the local power supply voltage from the master power supply voltage, Vcc, of the integrated circuit. If the temperature sensed is relatively high, the regulator increases the local power supply voltage, thus decreasing the delay and offsetting the increase in delay due to temperature.

Claims

1. A delay locked loop for an integrated circuit, comprising:

a delay element for receiving an input clock and for producing an output clock delayed with respect to the input clock;

a regulator for providing a power supply voltage for the delay element; and

a temperature sensor for sensing temperature and providing temperature information to the regulator, wherein the temperature sensor receives a temperature-independent voltage,

wherein the temperature information is used by the regulator to modify the power supply voltage.

2. The delay locked loop of claim 1, wherein the temperature information is used by the regulator to increase the power supply voltage when the sensed temperature increases and to decrease the power supply voltage when the sensed temperature decreases.

3. The delay locked loop of claim 1, wherein the delay element further receives at least one control signal for varying the delay.

4. The delay locked loop of claim 3, further comprising a phase detector for receiving the input clock and a representation of the output clock, and for producing the at least one control signal.

5. The delay locked loop of claim 4, further comprising a delay module, wherein the representation of the output clock comprises the output clock as delayed through the delay module.

6. The delay locked loop of claim 1, wherein the regulator provides the power supply voltage for the delay element by deriving it from a first voltage.

7. The delay locked loop of claim 6, wherein the first voltage comprises a master power supply voltage for the integrated circuit.

8. The delay locked loop of claim 1, wherein the temperature information comprises a plurality of digital signals.

9. The delay locked loop of claim 1, wherein the temperature information is quantized into a plurality of temperature ranges.

10. A method for controlling a delay locked loop in an integrated circuit, comprising:

receiving a temperature-independent voltage at a temperature sensor;

using the temperature sensor to sense a temperature of the integrated circuit; and

using the sensed temperature to set a value of a power supply for a delay element in the delay locked loop

11. The method of claim 10, wherein the value increases when the sensed temperature increases and decreases when the sensed temperature decreases.

12. The method of claim 10, wherein the delay element further receives at least one control signal for varying the delay.

13. The method of claim 12, wherein the at least one control signal results from a comparison of the phases of an input clock input to the delay element and a representation of an output clock output from the delay element.

14. The method of claim 13, wherein the representation of the output clock comprises the output clock as delayed through a delay module

15. The method of claim 10, wherein setting the value of the power supply comprises deriving the value from a first voltage.

16. The method of claim 15, wherein the first voltage comprises a master power supply voltage for the integrated circuit.

17. The method of claim 10, wherein sensing the temperature comprises rendering the sensed temperature into a plurality of digital signals.

18. The method of claim 10, wherein sensing the temperature comprises quantizing the sensed temperature into one of a plurality of temperature ranges.

19. An integrated circuit, comprising:

a subcircuit powered by a power supply node;

a regulator for providing a power supply voltage to the power supply node; and

a temperature sensor for providing temperature information to the regulator, wherein the temperature sensor receives a temperature-independent voltage,

wherein the temperature information is used by the regulator to modify the power supply voltage.

20. The integrated circuit of claim 19, wherein the temperature information is used by the regulator to increase the power supply voltage when the sensed temperature increases and to decrease the power supply voltage when the sensed temperature decreases.

21. The integrated circuit of claim 20, wherein increasing the power supply voltage when the sensed temperature increases and decreasing the power supply voltage when the sensed temperature decreases produce a temperature-independent delay in the delay element.

22. The integrated circuit of claim 19, wherein the subcircuit is a delay element.

23. The integrated circuit of claim 22, wherein the delay element further receives at least one control signal for varying a delay through the delay element.

24. The integrated circuit of claim 19, wherein the regulator provides the power supply voltage by deriving the power supply voltage from a first voltage.

25. The integrated circuit of claim 24, wherein the first voltage comprises a master power supply voltage for the integrated circuit.

26. The integrated circuit of claim 19, wherein the temperature information comprises a plurality of digital signals.

27. The integrated circuit of claim 19, wherein the temperature information is quantized into a plurality of temperature ranges.

28. A method for controlling a subcircuit in an integrated circuit, comprising:

receiving a temperature-independent voltage at a temperature sensor;

using the temperature sensor to sense a temperature of the integrated circuit; and

using the sensed temperature to set a value of a power supply for the subcircuit.

29. The method of claim 28, wherein the value increases when the sensed temperature increases and decreases when the sensed temperature decreases.

30. The integrated circuit of claim 28, wherein the subcircuit is a delay element.

31. The integrated circuit of claim 30, wherein the delay element receives at least one control signal for varying a delay through the delay element.

32. The method of claim 28, wherein setting the value of the power supply comprises deriving the value from a first voltage.

33. The method of claim 32, wherein the first voltage comprises a master power supply voltage for the integrated circuit.

34. The method of claim 28, wherein the sensed temperature is embodied in a plurality of digital signals.

35. The method of claim 28, wherein sensing the temperature comprises quantizing the sensed temperature into one of a plurality of temperature ranges.