USH1744H - Wireless remote sensing thermometer - Google Patents
Wireless remote sensing thermometer Download PDFInfo
- Publication number
- USH1744H USH1744H US08/532,944 US53294495A USH1744H US H1744 H USH1744 H US H1744H US 53294495 A US53294495 A US 53294495A US H1744 H USH1744 H US H1744H
- Authority
- US
- United States
- Prior art keywords
- temperature
- ring oscillator
- electrical signal
- oscillator
- frequency
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K1/00—Details of thermometers not specially adapted for particular types of thermometer
- G01K1/02—Means for indicating or recording specially adapted for thermometers
- G01K1/024—Means for indicating or recording specially adapted for thermometers for remote indication
Definitions
- the present invention relates to a ring oscillator that senses temperature and transmits temperature information to a radio receiver.
- Thermometric oscillators are one of many devices used to sense temperature.
- Other temperature sensing devices include thermocouples, resistance temperature detectors, and junction diodes. Typically these devices are placed in close proximity to the point where the measurement is desired and are connected by wires to other electronic components that process the output of the sensing device.
- the wires connecting to the sensing device are inconvenient.
- the sensing device may be moving while the other components preferably remain stationary.
- a temperature sensing point may be difficult to access, such as inside a nuclear reactor or some other harsh environment, where wired connections may be inconvenient.
- Another disadvantage is that the temperature range of the sensing device may not extend to the range of interest.
- Optical pyrometry is a well known technique for measuring temperature that does not require connecting wires to the point of measurement.
- Optical pyrometers measure the intensity of electromagnetic radiation from an object to determine temperature.
- the accuracy of the temperature measurement is dependent on the accuracy of the emissivity given for the object.
- intervening material between the object and the pyrometer may distort the temperature measurement.
- optical pyrometry is currently limited to elevated temperatures where emissivity is high.
- thermometric ring oscillator of the present invention addresses the problems described above, and may provide further related advantages.
- the following description of a thermometric ring oscillator does not preclude other embodiments and advantages of the present invention that may exist or become obvious to those skilled in the art.
- a temperature measuring device comprises a ring oscillator having a nominal oscillating frequency positioned at a location where temperature is to be measured.
- the ring oscillator emits electromagnetic radiation to an antenna located at a convenient distance from the ring oscillator.
- the antenna transforms the electromagnetic radiation into an electrical signal.
- a receiver receives the electrical signal and measures the frequency of the electrical signal to determine the corresponding temperature. The temperature may then be visually monitored from a display or electronically monitored by other devices.
- thermometric ring oscillator An advantage of the thermometric ring oscillator is that both temperature sensing and wireless transmission of temperature data are performed with a minimum of parts.
- thermometric ring oscillator may be incorporated with other electronic devices and circuits for measuring temperature under actual operating conditions.
- thermometric ring oscillator may be miniaturized by standard microelectronic fabrication techniques to allow maximum thermal coupling.
- Still another advantage is that the frequency of the ring oscillator may readily be measured to 1 part in 10 11 , thus making possible extremely precise temperature measurements.
- FIG. 1 is a circuit diagram of the thermometric ring oscillator.
- FIG. 2 is a detailed circuit diagram of a single inverter.
- FIG. 3 is an example of ring oscillator frequency versus temperature for higher temperatures.
- FIG. 4 is an example of ring oscillator frequency versus temperature for lower temperatures.
- thermometric oscillator 10 comprises an odd number of inverters 12 connected serially in a closed feedback loop.
- Other arrangements of an odd number of inverters 12 may be used, for example, a single inverter.
- a greater number of inverters has a lower ambient temperature oscillating frequency and a wider frequency variation over a percentage of temperature change than a smaller number of inverters.
- An optional feedback impedance (not shown) may also be used.
- FIGS. 3 and 4 are plots of frequency versus temperature for exemplary ring oscillator circuits.
- Thermometric ring oscillator 10 may be miniaturized by standard microelectronic fabrication techniques. Miniaturized thermometric oscillator 10 may be placed in close proximity to the point where a temperature measurement is desired, for example, on an integrated circuit microchip to ensure optimum thermal coupling. The nominal oscillating frequency of thermometric oscillator 10 may readily be measured to 1 part in 10 11 , thus making possible extremely precise temperature measurements.
- An antenna 14 may be located at a convenient location to transform electromagnetic radiation from thermometric oscillator 10 into an electrical signal.
- a receiver 16 is connected to antenna 14 to receive the electrical signal, measure the frequency of the signal, and determine the corresponding temperature of thermometric oscillator 10.
- the temperature may be determined, for example, from a lookup or calibration table.
- the temperature may be presented on a display 18 or from an output 19 in digital or analog form to other devices.
- FIG. 2 shows a detailed circuit diagram of an exemplary inverter 20 that may be used for making thermometric ring oscillator 10 in FIG. 1.
- a voltage source 22 biases inverter 20 to operate as an amplifier.
- Other oscillator circuits may be used, such as junction transistor circuits.
- the nominal oscillating frequency may be chosen to accommodate a wide variety of applications by selecting the number of inverters comprising thermometric ring oscillator 10, and may range over the frequency spectrum from about 100 GHZ down to the sub-audio frequency range of about 1 Hz.
- a typical range for the nominal oscillating frequency is from about 10 MHZ to about 150 MHZ. Changes in temperature may be detected by measuring the corresponding changes in the nominal oscillating frequency. Exemplary values of oscillating frequency versus temperature for thermometric ring oscillator 10 are plotted in FIGS. 3 and 4.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Temperature Or Quantity Of Heat (AREA)
Abstract
A temperature measuring device comprises a ring oscillator having a nominal oscillating frequency positioned at a location where temperature is to be measured. The ring oscillator emits electromagnetic radiation to an antenna located at a convenient distance from the ring oscillator. The antenna transforms the electromagnetic radiation into an electrical signal. A receiver receives the electrical signal and measures the frequency of the electrical signal to determine the corresponding temperature. The temperature may then be visually monitored from a display or electronically monitored by other devices.
Description
The present invention relates to a ring oscillator that senses temperature and transmits temperature information to a radio receiver.
Thermometric oscillators are one of many devices used to sense temperature. Other temperature sensing devices include thermocouples, resistance temperature detectors, and junction diodes. Typically these devices are placed in close proximity to the point where the measurement is desired and are connected by wires to other electronic components that process the output of the sensing device. In many applications, however, the wires connecting to the sensing device are inconvenient. In a production line, for example, the sensing device may be moving while the other components preferably remain stationary. In other applications, a temperature sensing point may be difficult to access, such as inside a nuclear reactor or some other harsh environment, where wired connections may be inconvenient.
Another disadvantage is that the temperature range of the sensing device may not extend to the range of interest.
Optical pyrometry is a well known technique for measuring temperature that does not require connecting wires to the point of measurement. Optical pyrometers measure the intensity of electromagnetic radiation from an object to determine temperature. However, the accuracy of the temperature measurement is dependent on the accuracy of the emissivity given for the object. Also, intervening material between the object and the pyrometer may distort the temperature measurement. Furthermore, optical pyrometry is currently limited to elevated temperatures where emissivity is high.
The thermometric ring oscillator of the present invention addresses the problems described above, and may provide further related advantages. The following description of a thermometric ring oscillator does not preclude other embodiments and advantages of the present invention that may exist or become obvious to those skilled in the art.
A temperature measuring device comprises a ring oscillator having a nominal oscillating frequency positioned at a location where temperature is to be measured. The ring oscillator emits electromagnetic radiation to an antenna located at a convenient distance from the ring oscillator. The antenna transforms the electromagnetic radiation into an electrical signal. A receiver receives the electrical signal and measures the frequency of the electrical signal to determine the corresponding temperature. The temperature may then be visually monitored from a display or electronically monitored by other devices.
An advantage of the thermometric ring oscillator is that both temperature sensing and wireless transmission of temperature data are performed with a minimum of parts.
Another advantage is that the thermometric ring oscillator may be incorporated with other electronic devices and circuits for measuring temperature under actual operating conditions.
A further advantage is that the thermometric ring oscillator may be miniaturized by standard microelectronic fabrication techniques to allow maximum thermal coupling.
Still another advantage is that the frequency of the ring oscillator may readily be measured to 1 part in 1011, thus making possible extremely precise temperature measurements.
The features and advantages summarized above in addition to other aspects of the present invention will become more apparent from the description, presented in conjunction with the following drawings.
FIG. 1 is a circuit diagram of the thermometric ring oscillator.
FIG. 2 is a detailed circuit diagram of a single inverter.
FIG. 3 is an example of ring oscillator frequency versus temperature for higher temperatures.
FIG. 4 is an example of ring oscillator frequency versus temperature for lower temperatures.
The following description is presented solely for the purpose of disclosing how the present invention may be made and used. The scope of the invention is defined by the claims.
Referring to FIG. 1, a thermometric oscillator 10 comprises an odd number of inverters 12 connected serially in a closed feedback loop. Other arrangements of an odd number of inverters 12 may be used, for example, a single inverter. Generally, a greater number of inverters has a lower ambient temperature oscillating frequency and a wider frequency variation over a percentage of temperature change than a smaller number of inverters. An optional feedback impedance (not shown) may also be used. As the temperature environment of thermometric oscillator 10 changes, the switching speed of the transistors of which the inverters are comprised changes, causing the oscillating frequency to change. FIGS. 3 and 4 are plots of frequency versus temperature for exemplary ring oscillator circuits. Thermometric ring oscillator 10 may be miniaturized by standard microelectronic fabrication techniques. Miniaturized thermometric oscillator 10 may be placed in close proximity to the point where a temperature measurement is desired, for example, on an integrated circuit microchip to ensure optimum thermal coupling. The nominal oscillating frequency of thermometric oscillator 10 may readily be measured to 1 part in 1011, thus making possible extremely precise temperature measurements.
An antenna 14 may be located at a convenient location to transform electromagnetic radiation from thermometric oscillator 10 into an electrical signal. A receiver 16 is connected to antenna 14 to receive the electrical signal, measure the frequency of the signal, and determine the corresponding temperature of thermometric oscillator 10. The temperature may be determined, for example, from a lookup or calibration table. The temperature may be presented on a display 18 or from an output 19 in digital or analog form to other devices.
FIG. 2 shows a detailed circuit diagram of an exemplary inverter 20 that may be used for making thermometric ring oscillator 10 in FIG. 1. A voltage source 22 biases inverter 20 to operate as an amplifier. Other oscillator circuits may be used, such as junction transistor circuits. The nominal oscillating frequency may be chosen to accommodate a wide variety of applications by selecting the number of inverters comprising thermometric ring oscillator 10, and may range over the frequency spectrum from about 100 GHZ down to the sub-audio frequency range of about 1 Hz. A typical range for the nominal oscillating frequency is from about 10 MHZ to about 150 MHZ. Changes in temperature may be detected by measuring the corresponding changes in the nominal oscillating frequency. Exemplary values of oscillating frequency versus temperature for thermometric ring oscillator 10 are plotted in FIGS. 3 and 4.
Other modifications, variations, and applications of the present invention may be made in accordance with the above teachings other than as specifically described to practice the invention within the scope of the following claims.
Claims (7)
1. A device for remotely measuring a temperature at a selected location, comprising:
a ring oscillator having a nominal frequency that changes with changes in said temperature, wherein said oscillator is operably coupled to said location, and wherein said oscillator emits electromagnetic radiation at said frequency;
an antenna operably coupled for transforming said electromagnetic radiation to an electrical signal; and
a receiver operably coupled to said antenna for receiving said electrical signal to measure said frequency from said electrical signal for determining said temperature.
2. The device of claim 1, wherein said ring oscillator comprises a number of inverters serially connected in a closed loop.
3. The device of claim 1, wherein said nominal frequency is in the range of approximately 1 Hz to approximately 100 GHZ.
4. The device of claim 1, further comprising a display to display said temperature.
5. The device of claim 1, wherein said receiver outputs said temperature as an analog waveform.
6. The device of claim 1, wherein said receiver outputs said temperature as digital data.
7. The device of claim 1, further comprising a power source operably coupled to said oscillator.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/532,944 USH1744H (en) | 1995-09-21 | 1995-09-21 | Wireless remote sensing thermometer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/532,944 USH1744H (en) | 1995-09-21 | 1995-09-21 | Wireless remote sensing thermometer |
Publications (1)
Publication Number | Publication Date |
---|---|
USH1744H true USH1744H (en) | 1998-08-04 |
Family
ID=24123853
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US08/532,944 Abandoned USH1744H (en) | 1995-09-21 | 1995-09-21 | Wireless remote sensing thermometer |
Country Status (1)
Country | Link |
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US (1) | USH1744H (en) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5965817A (en) * | 1998-07-28 | 1999-10-12 | Quasar International, Inc. | Temperature compensation of resonant frequency measurements for the effects of temperature variations |
US20050135456A1 (en) * | 2003-12-22 | 2005-06-23 | Hsin-Chou Lee | [radio frequency temperature sensor and method of calibrating temperature therefor] |
US6948388B1 (en) | 2003-12-18 | 2005-09-27 | The United States Of America As Represented By The Secretary Of The Navy | Wireless remote sensor |
US20050225415A1 (en) * | 2004-04-12 | 2005-10-13 | Mahony Michael J | Apparatus for monitoring temperature and method for operating same |
CN100397057C (en) * | 2003-12-30 | 2008-06-25 | 凌阳科技股份有限公司 | Radio frequency temperature inductor and temperature correction method therefor |
US20080187025A1 (en) * | 2007-02-06 | 2008-08-07 | Chevron U.S.A., Inc. | Temperature sensor having a rotational response to the environment |
US20080184787A1 (en) * | 2007-02-06 | 2008-08-07 | Chevron U.S.A., Inc. | Temperature and pressure transducer |
US20080253230A1 (en) * | 2007-04-13 | 2008-10-16 | Chevron U.S.A. Inc. | System and method for receiving and decoding electromagnetic transmissions within a well |
US20090031796A1 (en) * | 2007-07-30 | 2009-02-05 | Coates Don M | System and method for sensing pressure using an inductive element |
US20090174409A1 (en) * | 2007-09-04 | 2009-07-09 | Chevron U.S.A., Inc. | Downhole sensor interrogation employing coaxial cable |
US7636052B2 (en) | 2007-12-21 | 2009-12-22 | Chevron U.S.A. Inc. | Apparatus and method for monitoring acoustic energy in a borehole |
US20110081256A1 (en) * | 2009-10-05 | 2011-04-07 | Chevron U.S.A., Inc. | System and method for sensing a liquid level |
US20110128003A1 (en) * | 2009-11-30 | 2011-06-02 | Chevron U.S.A, Inc. | System and method for measurement incorporating a crystal oscillator |
US8390471B2 (en) | 2006-09-08 | 2013-03-05 | Chevron U.S.A., Inc. | Telemetry apparatus and method for monitoring a borehole |
EP3038256A3 (en) * | 2014-12-01 | 2016-10-05 | MediaTek, Inc | Inverter and ring oscillator with high temperature sensitivity |
CN106875878B (en) * | 2017-02-27 | 2020-04-14 | 京东方科技集团股份有限公司 | Temperature detection circuit, display panel and display device |
Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3596262A (en) * | 1968-01-08 | 1971-07-27 | Southwest Res Inst | Telemetry measuring apparatus |
US3971362A (en) * | 1972-10-27 | 1976-07-27 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Miniature ingestible telemeter devices to measure deep-body temperature |
US4025912A (en) * | 1976-07-19 | 1977-05-24 | The United States Of America As Represented By The Secretary Of The Navy | Method and apparatus for remotely transducing and transmitting pressure and temperature changes |
US4140999A (en) * | 1976-05-03 | 1979-02-20 | Robertshaw Controls Company | Transformer hot spot detection system |
US4297557A (en) * | 1976-05-03 | 1981-10-27 | Robertshaw Controls Company | Microwave oven temperature indicator and control means |
US4448549A (en) * | 1981-03-10 | 1984-05-15 | Citizen Watch Company Limited | Temperature sensing device |
US4471354A (en) * | 1981-11-23 | 1984-09-11 | Marathon Medical Equipment Corporation | Apparatus and method for remotely measuring temperature |
US4549818A (en) * | 1982-12-10 | 1985-10-29 | Citizen Watch Co., Ltd. | Temperature detector |
US4658407A (en) * | 1983-12-21 | 1987-04-14 | Kabushiki Kaisha Toshiba | Electronic clinical thermometer with power shut-off at maximum temperature |
US4689621A (en) * | 1986-03-31 | 1987-08-25 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Temperature responsive transmitter |
US4874252A (en) * | 1987-12-24 | 1989-10-17 | W. C. Heraeus Gmbh | Electronic thermometer |
US4918423A (en) * | 1987-07-23 | 1990-04-17 | Bridgestone Corporation | Tire inspection device |
US5214668A (en) * | 1990-09-28 | 1993-05-25 | Nec Corporation | Temperature detector and a temperature compensated oscillator using the temperature detector |
US5374822A (en) * | 1989-01-24 | 1994-12-20 | Robert Bosch Gmbh | Optical transmitter for producing an optical signal indicative of temperature |
-
1995
- 1995-09-21 US US08/532,944 patent/USH1744H/en not_active Abandoned
Patent Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3596262A (en) * | 1968-01-08 | 1971-07-27 | Southwest Res Inst | Telemetry measuring apparatus |
US3971362A (en) * | 1972-10-27 | 1976-07-27 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Miniature ingestible telemeter devices to measure deep-body temperature |
US4140999A (en) * | 1976-05-03 | 1979-02-20 | Robertshaw Controls Company | Transformer hot spot detection system |
US4297557A (en) * | 1976-05-03 | 1981-10-27 | Robertshaw Controls Company | Microwave oven temperature indicator and control means |
US4025912A (en) * | 1976-07-19 | 1977-05-24 | The United States Of America As Represented By The Secretary Of The Navy | Method and apparatus for remotely transducing and transmitting pressure and temperature changes |
US4448549A (en) * | 1981-03-10 | 1984-05-15 | Citizen Watch Company Limited | Temperature sensing device |
US4471354A (en) * | 1981-11-23 | 1984-09-11 | Marathon Medical Equipment Corporation | Apparatus and method for remotely measuring temperature |
US4549818A (en) * | 1982-12-10 | 1985-10-29 | Citizen Watch Co., Ltd. | Temperature detector |
US4658407A (en) * | 1983-12-21 | 1987-04-14 | Kabushiki Kaisha Toshiba | Electronic clinical thermometer with power shut-off at maximum temperature |
US4689621A (en) * | 1986-03-31 | 1987-08-25 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Temperature responsive transmitter |
US4918423A (en) * | 1987-07-23 | 1990-04-17 | Bridgestone Corporation | Tire inspection device |
US4874252A (en) * | 1987-12-24 | 1989-10-17 | W. C. Heraeus Gmbh | Electronic thermometer |
US5374822A (en) * | 1989-01-24 | 1994-12-20 | Robert Bosch Gmbh | Optical transmitter for producing an optical signal indicative of temperature |
US5214668A (en) * | 1990-09-28 | 1993-05-25 | Nec Corporation | Temperature detector and a temperature compensated oscillator using the temperature detector |
Cited By (33)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5965817A (en) * | 1998-07-28 | 1999-10-12 | Quasar International, Inc. | Temperature compensation of resonant frequency measurements for the effects of temperature variations |
US6948388B1 (en) | 2003-12-18 | 2005-09-27 | The United States Of America As Represented By The Secretary Of The Navy | Wireless remote sensor |
US20050135456A1 (en) * | 2003-12-22 | 2005-06-23 | Hsin-Chou Lee | [radio frequency temperature sensor and method of calibrating temperature therefor] |
US7066643B2 (en) * | 2003-12-22 | 2006-06-27 | Sunplus Technology Co,Ltd. | Radio frequency temperature sensor and method of calibrating temperature therefor |
CN100397057C (en) * | 2003-12-30 | 2008-06-25 | 凌阳科技股份有限公司 | Radio frequency temperature inductor and temperature correction method therefor |
US20050225415A1 (en) * | 2004-04-12 | 2005-10-13 | Mahony Michael J | Apparatus for monitoring temperature and method for operating same |
US7215212B2 (en) | 2004-04-12 | 2007-05-08 | General Electric Company | Apparatus for monitoring temperature and method for operating same |
US8390471B2 (en) | 2006-09-08 | 2013-03-05 | Chevron U.S.A., Inc. | Telemetry apparatus and method for monitoring a borehole |
US20080184787A1 (en) * | 2007-02-06 | 2008-08-07 | Chevron U.S.A., Inc. | Temperature and pressure transducer |
US20110068794A1 (en) * | 2007-02-06 | 2011-03-24 | Chevron U.S.A., Inc. | Temperature and pressure transducer |
US8143906B2 (en) | 2007-02-06 | 2012-03-27 | Chevron U.S.A. Inc. | Temperature and pressure transducer |
US7810993B2 (en) | 2007-02-06 | 2010-10-12 | Chevron U.S.A. Inc. | Temperature sensor having a rotational response to the environment |
US8083405B2 (en) | 2007-02-06 | 2011-12-27 | Chevron U.S.A. Inc. | Pressure sensor having a rotational response to the environment |
US7863907B2 (en) | 2007-02-06 | 2011-01-04 | Chevron U.S.A. Inc. | Temperature and pressure transducer |
US20080187025A1 (en) * | 2007-02-06 | 2008-08-07 | Chevron U.S.A., Inc. | Temperature sensor having a rotational response to the environment |
US20110026563A1 (en) * | 2007-02-06 | 2011-02-03 | Chevron U.S.A. Inc. | Pressure sensor having a rotational response to the environment |
US20080253230A1 (en) * | 2007-04-13 | 2008-10-16 | Chevron U.S.A. Inc. | System and method for receiving and decoding electromagnetic transmissions within a well |
US8106791B2 (en) | 2007-04-13 | 2012-01-31 | Chevron U.S.A. Inc. | System and method for receiving and decoding electromagnetic transmissions within a well |
US20110022336A1 (en) * | 2007-07-30 | 2011-01-27 | Chevron U.S.A. Inc. | System and method for sensing pressure using an inductive element |
US20090031796A1 (en) * | 2007-07-30 | 2009-02-05 | Coates Don M | System and method for sensing pressure using an inductive element |
US7841234B2 (en) | 2007-07-30 | 2010-11-30 | Chevron U.S.A. Inc. | System and method for sensing pressure using an inductive element |
US8261607B2 (en) | 2007-07-30 | 2012-09-11 | Chevron U.S.A. Inc. | System and method for sensing pressure using an inductive element |
US9547104B2 (en) | 2007-09-04 | 2017-01-17 | Chevron U.S.A. Inc. | Downhole sensor interrogation employing coaxial cable |
US20090174409A1 (en) * | 2007-09-04 | 2009-07-09 | Chevron U.S.A., Inc. | Downhole sensor interrogation employing coaxial cable |
US7636052B2 (en) | 2007-12-21 | 2009-12-22 | Chevron U.S.A. Inc. | Apparatus and method for monitoring acoustic energy in a borehole |
US8353677B2 (en) | 2009-10-05 | 2013-01-15 | Chevron U.S.A. Inc. | System and method for sensing a liquid level |
US20110081256A1 (en) * | 2009-10-05 | 2011-04-07 | Chevron U.S.A., Inc. | System and method for sensing a liquid level |
US8784068B2 (en) | 2009-10-05 | 2014-07-22 | Chevron U.S.A. Inc. | System and method for sensing a liquid level |
US20110128003A1 (en) * | 2009-11-30 | 2011-06-02 | Chevron U.S.A, Inc. | System and method for measurement incorporating a crystal oscillator |
US10488286B2 (en) | 2009-11-30 | 2019-11-26 | Chevron U.S.A. Inc. | System and method for measurement incorporating a crystal oscillator |
EP3038256A3 (en) * | 2014-12-01 | 2016-10-05 | MediaTek, Inc | Inverter and ring oscillator with high temperature sensitivity |
CN106875878B (en) * | 2017-02-27 | 2020-04-14 | 京东方科技集团股份有限公司 | Temperature detection circuit, display panel and display device |
US11422040B2 (en) | 2017-02-27 | 2022-08-23 | Boe Technology Group Co., Ltd. | Temperature detection circuit, display panel and display device |
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Owner name: NAVY, UNITED STATES OF AMERICA, AS REPRESENTED BY Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CLAYTON, STANLEY R.;ROSER, MARK R.;RUSSELL, STEPHEN D.;AND OTHERS;REEL/FRAME:007684/0792 Effective date: 19950920 |
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