IC monitoring chip and a method for monitoring temperature of a component in a computer

• US 6,169,442 B1
• Filed: 04/13/1999
• Issued: 01/02/2001
• Est. Priority Date: 04/13/1999
• Status: Expired due to Term

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: Meehan, Patrick, Thomson, David, Blake, John
• Primary Examiner(s): Wells, Kenneth B.
• Application Number:
  US09/291,409
• Time in Patent Office: 630 Days
• Field of Search: 327/307, 327/512, 327/513, 374/172, 324/207.12
• US Class Current: 327/513
• CPC Class Codes: G01K 13/00 Thermometers specially adapted for specific purposes
• CPC Class Codes: G01K 7/01 using semiconducting elements having PN junctions G01K7/02, G01K7/16, G01K7/30 take precedence
• CPC Class Codes: G06F 1/206 comprising thermal management
• CPC Class Codes: G06F 11/3024 where the computing system component is a central processing unit [CPU]
• CPC Class Codes: G06F 11/3058 Monitoring arrangements for monitoring environmental properties or parameters of the computing system or of the computing system component, e.g. monitoring of power, currents, temperature, humidity, position, vibrations thermal management in cooling arrangements of a computing system G06F1/206
• CPC Class Codes: G06F 11/3093 Configuration details thereof, e.g. installation, enabling, spatial arrangement of the probes

Abstract

An IC monitoring chip (10) for remotely monitoring the output of a thermal diode (5) formed in the substrate of a CPU (2) for monitoring the temperature of a thermal plate (3) of the CPU (2) comprises a signal conditioning circuit (12) which relays the output from the diode (5) to an analog-to-digital converter (14), which in turns outputs a two'"'"'s compliment signal to an adder (22). The adder (22) adds the two'"'"'s compliment signal to a temperature offset value stored in a temperature offset register (17), which compensates for the temperature difference between the diode (5) and the thermal plate (3). Comparators (24) and (25) compare the output from the adder (22) with upper and lower predetermined temperature limits in upper and lower limit registers (19) and (20) for determining the temperature of the thermal plate (3). The temperature offset value is stored in ROM (35) of the computer (1) and is written to the register (17) each time the computer (1) is powered up. The IC chip (10) operates independently of the CPU (2).

Claims

1. An integrated circuit monitoring chip for monitoring the output of a temperature sensing element, the IC chip comprising:

an on-chip first input means for receiving a first input signal from the temperature sensing element corresponding to a temperature value sensed by the temperature sensing element,

an on-chip temperature offset storing means for storing a temperature offset value,

an on-chip adding means for adding the stored temperature offset value and the temperature value of the first input signal,

an on-chip output means for outputting an output signal from the IC chip in response to the output from the adding means, and

an on-chip second input means being provided to the temperature offset storing means for facilitating writing the temperature offset value to the temperature offset storing means.

2. An IC chip as claimed in claim 1 in which the temperature offset storing means comprises a temperature offset register in the chip for storing the temperature offset value in digital form.

3. A IC chip as claimed in claim 1 in which the adding means adds the absolute values of the temperature value of the first input signal and the temperature offset value.

4. An IC chip as claimed in claim 1 in which the temperature offset value is stored in two'"'"'s compliment format in the offset temperature storing means.

5. An IC chip as claimed in claim 1 in which an on-chip upper and lower limit storing means for storing respective upper and lower predetermined temperature limit values is provided, and an on-chip comparing means for comparing the output from the adding means with the respective upper and lower predetermined temperature limit values is provided.

6. An IC chip as claimed in claim 5 in which the upper and lower limit storing means comprises an upper limit register and a lower limit register provided in the chip for respectively storing the upper and lower predetermined temperature limit values in digital form.

7. An IC chip as claimed in claim 6 in which the comparing means comprises a pair of comparators provided in the chip, one comparator being provided for comparing the output from the adding means with the stored upper predetermined temperature limit value stored in the upper limit register, and the other comparator being provided for comparing the output of the adding means with the lower predetermined temperature limit value stored in the lower limit register.

8. An IC chip as claimed in claim 5 in which the upper and lower predetermined temperature limit values are stored in two'"'"'s compliment format in the upper and lower limit storing means.

9. An IC chip as claimed in claim 5 in which the output means outputs an alerting signal in the event of the output from the adding means falling outside the upper and lower predetermined temperature limit values.

10. An IC chip as claimed in claim 5 in which an on-chip status storing means is provided for storing the status of the output of the comparing means.

11. An IC chip as claimed in claim 10 in which the status storing means comprises two status registers provided in the chip corresponding to the respective comparators for storing the status of the outputs of the respective comparators.

12. An IC chip as claimed in claim 5 in which the second input means is adapted for facilitating writing the upper and lower predetermined temperature limit values to the upper and lower limit storing means.

13. An IC chip as claimed in claim 1 in which the first input means comprises an on-chip signal conditioning circuit for receiving the first input signal in analog form from the temperature sensing element.

14. An IC chip as claimed in claim 13 in which an on-chip analog to digital converter is provided for receiving the output from the signal conditioning circuit and for outputting a digital signal corresponding to the temperature value of the first input signal to the adding means.

15. An IC chip as claimed in claim 14 in which the digital signal outputted from the analog to digital converter is outputted in two'"'"'s compliment format.

16. An IC chip as claimed in claim 13 in which the signal conditioning circuit is adapted for receiving the first input signal from a remotely located temperature sensing element.

17. An IC chip as claimed in claim 13 in which an on-chip temperature sensing element is located in the chip, and the on-chip signal conditioning circuit is adapted for receiving a second input signal from the on-chip temperature sensing element corresponding to a temperature value sensed by the on-chip temperature sensing element.

18. An IC chip as claimed in claim 13 in which two on-chip signal conditioning circuits are provided in the chip for receiving respectively the first input signal and a second input signal from an on-chip temperature sensing element in the chip, the second input signal corresponding to a temperature value sensed by the on-chip temperature sensing element, and an on-chip means is provided in the chip for alternately relaying the temperature values corresponding to the first and second input signals to the adding means.

19. An IC chip as claimed in claim 18 in which the temperature offset storing means stores two temperature offset values corresponding to the respective remotely located and on-chip temperature sensing elements for adding to the temperature values of the respective first and second input signals from the corresponding remotely located and on-chip temperature sensing elements in the adding means.

20. An IC chip as claimed in claim 19 in which each temperature offset storing means comprises an on-chip temperature offset register.

21. An IC chip as claimed in claim 18 in which the upper and lower limit storing means stores two respective upper and lower predetermined temperature limit values corresponding to the respective remotely located and on-chip temperature sensing elements for comparison with the respective outputs from the adding means which correspond to the first and second input signals.

22. An IC chip as claimed in claim 21 in which the upper and lower limit storing means comprises two upper and two lower limit registers for storing the respective upper and lower predetermined temperature limit values corresponding to the respective temperature sensing elements.

23. A computer comprising the IC monitoring chip as claimed in claim 1 in which the computer comprises a storing means for storing the temperature offset value and a writing means for writing the temperature offset value stored in the computer storing means to the temperature offset storing means of the IC chip.

24. A computer as claimed in claim 23 in which the computer storing means further stores the upper and lower predetermined temperature limit values and the writing means is adapted for writing the respective upper and lower predetermined temperature limit values to the upper and lower limit storing means of the IC chip.

25. A computer as claimed in claim 23 in which the computer storing means is provided by a read only memory, which is adapted for receiving the temperature offset value during manufacture of the computer.

26. A computer as claimed in claim 23 in which the writing means comprises a computer programme.

27. A computer as claimed in claim 23 in which the writing means is adapted to write the temperature offset value from the computer storing means into the temperature offset storing means of the IC chip on power up of the computer.

28. A computer as claimed in claim 23 in which the temperature sensing element is located in the computer remotely of the IC chip.

29. A method for monitoring the temperature of a component in a computer wherein a temperature difference exists between the component and a temperature sensing element for measuring the temperature of the component, the method comprising using an IC monitoring chip for monitoring an output temperature value from the temperature sensing element, storing a temperature offset value corresponding to the temperature difference in an on-chip temperature offset storing means located in the IC chip, and adding the output temperature value and the temperature offset value for determining the temperature of the component.

30. A method as claimed in claim 29 in which the temperature offset storing means is provided by a temperature offset register, and the temperature offset value is written to the temperature offset register by a writing means in the computer.

31. A method as claimed in claim 29 in which the method further comprises storing the temperature offset value in a storing means in the computer.

32. A method as claimed in claim 31 in which the temperature offset value is written to the computer storing means during manufacture of the computer.

33. A method as claimed in claim 31 in which the temperature offset value is written from the computer storing means to the temperature offset register in the IC chip by the writing means on power up of the computer.