Two-pin thermal sensor calibration interface

• US 6,774,653 B2
• Filed: 08/22/2001
• Issued: 08/10/2004
• Est. Priority Date: 08/22/2001
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Gold, Spencer M., House, Kenneth, Gauthier, Claude R.
• Primary Examiner(s): Cuneo, Kamand
• Assistant Examiner(s): PATEL, PARESH H
• Application Number:
  US09/935,385
• Publication Number:
  US 20030038648A1
• Time in Patent Office: 1,084 Days
• Field of Search: 324/760, 324/153, 702/132, 702/99, 702/104, 702/130, 702/176, 702/182, 702/183
• US Class Current: 257/48
• CPC Class Codes: G01K 15/00 Testing or calibrating of thermometers
• CPC Class Codes: G01K 7/42 Circuits effecting compensation of thermal inertia; Circuits for predicting the stationary value of a temperature

Abstract

A sensor and method are provided for sensing a physical stimulus in an integrated amount, such as thermal energy and produce a signal that indicates a quantitative value of the physical stimulus along with a value that indicates the operability of the sensor and a value that indicates a sense operation is in process. The sensor and method minimize the number of input and output pins necessary for a sensor to report a measurement response of a physical stimulus.

Claims

1. A thermal sensor in an integrated circuit comprising:

a register to hold a response of said thermal sensor; and

an Input/Output (I/O) interface having an input node to receive an input trigger to trigger said thermal sensor to output on an output node of said interface an output signal that includes a first value that indicates said thermal sensor is sensing the temperature of said integrated circuit, a second value representative of said response held by said register, and a third value generated by said thermal sensor that indicates said thermal sensor is functioning properly.

2. The thermal sensor of claim 1, wherein said Input/Output interface comprises a digital Input/Output interface having at least one input node capable of receiving a digital input and at least one output node capable of asserting a digital output.

3. The thermal sensor of claim 2, wherein said input node and output node comprises at least two electrical contacts capable of providing an off chip interface.

4. The thermal sensor of claim 1, wherein said integrated circuit comprises a microprocessor.

5. The thermal sensor of claim 1, wherein said integrated circuit comprises a very large scale integration (VLSI) circuit.

6. The thermal sensor of claim 1, wherein said thermal sensor appends said value that indicates said thermal sensor is functioning properly to said response of said thermal sensor.

7. The thermal sensor of claim 1, wherein said thermal sensor is a calibrated sensor.

8. The thermal sensor of claim 1, wherein said thermal sensor is en active sensor.

9. In an integrated circuit having a thermal sensor, a method for said thermal sensor to provide an indication that said thermal sensor is functioning properly, the method comprising the steps of:

asserting an input signal at a first Input/Output pin of said thermal sensor to initiate thermal sensing of said integrated circuit by said thermal sensor;

sensing by said thermal sensor a temperature of said integrated circuit; and

asserting an output signal on a second Input/Output pin of said thermal sensor by said thermal sensor wherein said output signal provides a first value indicating said thermal sensor is sensing said temperature, a second value representative of said temperature of said integrated circuit, and a third value that provides said indication that said thermal sensor is functioning properly.

10. The method of claim 9 further comprising the step of writing said temperature of said integrated circuit to a register of said thermal sensor.

11. The method of claim 9, further comprising the step of asserting a status signal on said second Input/Output pin of said thermal sensor during said step of sensing by said thermal sensor a temperature of said integrated circuit to indicate that said sensing is occurring.

12. The method of claim 9, wherein said output signal comprises a first portion and a second pin.

13. The method of claim 12, wherein said first portion of said output signal comprises a value representative of said temperature of said integrated circuit.

14. The method of claim 12, wherein said second portion of said output signal comprises a value representative of said indication that said thermal sensor is functioning properly.

15. The method of claim 13, wherein said value representative of said temperature indicates an absolute temperature.

16. The method of claim 13, wherein said value representative of said temperature indicates a relative temperature.