Multiple pressure sensing system

• US 6,401,541 B1
• Filed: 11/03/1999
• Issued: 06/11/2002
• Est. Priority Date: 11/03/1999
• Status: Active Grant

• Current Assignee: Kulite Semiconductor Products Inc
• Original Assignee: Kulite Semiconductor Products Inc
• Inventors: Kurtz, Anthony D.
• Primary Examiner(s): Fuller, Benjamin R.
• Assistant Examiner(s): AW MUSSE, ABDULLAHI H
• Application Number:
  US09/432,467
• Time in Patent Office: 951 Days
• Field of Search: 737/20, 737/21, 737/23, 737/25, 737/26, 737/27, 737/56, 737/16, 737/17, 737/18, 737/19, 340/870.37
• US Class Current: 73/716
• CPC Class Codes: G01L 15/00 Devices or apparatus for measuring two or more fluid pressure values simultaneously
• CPC Class Codes: G01L 9/065 with temperature compensating means non electric temperature compensating means G01L19/04

Abstract

A method for measuring multiple pressures and a pressure sensing system for accomplishing the same. The method for measuring a plurality of pressures includes, exposing each of a plurality of pressure sensors to a corresponding plurality of environments each having a corresponding pressure to be measured, determining how frequently to measure each of the plurality of pressures, determining a sequence for utilizing the pressure sensors to measure the corresponding plurality of pressures, the sequence being dependent upon the determined frequency for each of the plurality of pressures and selectively utilizing each of the plurality of pressure sensors according to the determined sequence to measure the pressure to which it is exposed.

Claims

1. A pressure sensing system adapted for measuring a plurality of pressures, said system comprising:

a plurality of pressure sensing assemblies each positioned to be exposable to a corresponding one of a plurality of discrete environments exhibiting a corresponding one of said plurality of pressures to be measured and varying in at least one degree of hostility;

a microcontroller; and

,

at least one switching device coupled between each of said plurality of pressure sensing assemblies and said microcontroller for selectively coupling each of said plurality of pressure sensing assemblies to said microcontroller in a predetermined sequence responsively to said microcontroller, wherein each of said pressure sensing assemblies includes first and second outputs, and said at least one switching device comprises a first switching device coupled between said first output of each of said plurality of pressure sensing assemblies and said microcontroller and a second switching device coupled between said second output of each of said plurality of pressure sensing assemblies and said microcontroller.

2. The system of claim 1, further comprising a control line coupled to said first and second switching devices and said microcontroller, wherein said microcontroller outputs a control signal via said control line being indicative of one of said plurality of pressure sensing assemblies, and said first and second switching devices couple said one of said plurality of pressure sensing assemblies to said microcontroller responsively to said control signal.

3. The system of claim 2, wherein said microprocessor includes a plurality of memory addresses having instructions stored thereat for correcting for inherent errors associated with each of said plurality of pressure sensing assemblies.

4. The system of claim 3, further comprising a plurality resistors each respectively coupled to a corresponding one of said plurality of pressure sensing assemblies and for monitoring a voltage drop across said corresponding pressure sensing assembly.

5. The system of claim 4, further comprising at least one compensation switching device for selectively coupling one of said resistors to said microcontroller and being coupled between each of said resistors and said microcontroller.

6. The system of claim 5, wherein said at least one compensation switching device is further electronically coupled to said control line and responsive to said control signal to electronically couple at least one of said plurality of resistors corresponding to said one of said plurality of pressure sensing assemblies to said microcontroller.

7. The system of claim 1, wherein the respective degree of hostility of each of said plurality of environments may cause an error in an output of said respectively associated pressure sensing assembly, said microcontroller includes means for correcting at least one of said errors, and said microcontroller is exposed to an environment having a relatively mild degree of hostility as compared to at least one of said plurality of environments.

8. The system of claim 7, wherein said inherent errors associated with each of said plurality of pressure sensing assemblies are selected from the group consisting of:

a zero error, a span error, an environment induced zero error and an environment induced span error.

9. The system of claim 1, further comprising at least one memory coupled to said microcontroller and for storing at least one lookup table having a plurality of data entries each respectively associated with at least one of said plurality of pressure sensing assemblies and a temperature, wherein said microcontroller utilizes a select one of said data entries to correct an output of one of said associated pressure sensing assemblies.

10. The system of claim 1 wherein said predetermined sequence is dependent upon a determined frequency for measuring each of said plurality of pressures.

11. The system of claim 1, wherein each of said pressure sensing assemblies comprises a piezoresistive bridge assembly.

12. A method for measuring a plurality of pressures comprising the steps of:

exposing each of a plurality of pressure sensors to a corresponding one of a plurality of discrete environments varying in degree of hostility and each exhibiting a corresponding one of said pressures to be measured;

determining how frequently to measure each of said corresponding pressures with said pressure sensors;

determining a sequence for utilizing said pressure sensors to measure said corresponding plurality of pressures, said sequence being dependent upon said determined frequency for measuring each of said corresponding pressures; and

,

selectively coupling each of said plurality of pressure sensors to a microcontroller according to said determined sequence.

13. The method of claim 12, wherein said step of selectively coupling each of said plurality of pressure sensors comprises sequentially electronically coupling each of said plurality of pressure sensors to said microcontroller according to said determined sequence.

14. The method of claim 12, wherein the respective degree of hostility of at least one of said plurality of environments may cause an error in measuring said corresponding pressure thereof, and said method further comprises the steps of:

generating a first value at least partially indicative of a first of said corresponding pressures utilizing said microcontroller and a first of said pressure sensors, wherein said first pressure sensor is exposed to a first of said plurality of environments having said first corresponding pressure;

determining a first degree of hostility of said first environment; and

,

adjusting said first value responsively to said determined first degree of hostility using said microcontroller.

15. The method of claim 14, further comprising the step of:

generating a control signal to which said selective coupling is responsive to.

16. The method of claim 14, further comprising the step of:

generating a second value at least partially indicative of a second of said corresponding pressures utilizing said microcontroller and a second of said pressure sensors, wherein said second pressure sensor is exposed to a second of said plurality of environments having said second corresponding pressure;

determining a second degree of hostility of said second environment; and

,

adjusting said second value responsively to said determined second degree of hostility using said microcontroller.

17. The method of claim 16, wherein said step of adjusting said first value is independent of said step of adjusting said second value.