CN2725866Y - Digital temp measuring circuit - Google Patents
Digital temp measuring circuit Download PDFInfo
- Publication number
- CN2725866Y CN2725866Y CN 200420061227 CN200420061227U CN2725866Y CN 2725866 Y CN2725866 Y CN 2725866Y CN 200420061227 CN200420061227 CN 200420061227 CN 200420061227 U CN200420061227 U CN 200420061227U CN 2725866 Y CN2725866 Y CN 2725866Y
- Authority
- CN
- China
- Prior art keywords
- microprocessor
- circuit
- discharge
- digital
- resistance
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Measuring Temperature Or Quantity Of Heat (AREA)
Abstract
The utility model discloses a digital temp measuring circuit, comprising a thermal resistor, a reference resistance, a discharge circuit, a microprocessor and a capacitance. The first I/O port of the microprocessor is orderly connected with the thermal resistor and the capacitance in series to compose a first charging loop, the second I/O port of the microprocessor is orderly connected with the reference resistance and the capacitance in series to compose a second charging loop, and the third I/O port of the microprocessor is orderly connected with the discharge circuit in series to compose a discharge loop. The advantages of the utility model are that the digital temp measuring circuit only needs to adopt a small amount of basic elements to simply connect with the microprocessor, having simple structure, and the digital temp measuring circuit can proceed the digital measurement of the temperature without using an A/D analog to digital converter, having low cost.
Description
[technical field]
The utility model relates to a kind of temperature measurement circuit, especially relates to a kind of digital temperature measurement circuit.
[background technology]
Existing digital temperature measurement circuit generally is after employing is carried out temperature sampling by thermal sensing element, convert digital quantity to through the A/D analog to digital converter, send into microprocessor portion again and carry out the scheme that computing obtains actual temperature value, owing to have the A/D analog to digital converter thereby have complex structure, the higher shortcoming of cost.
[utility model content]
The purpose of this utility model be propose a kind of simple in structure, cost is low, do not use the digital temperature measurement circuit of A/D analog to digital converter.
The technical scheme that realizes above-mentioned purpose is: a kind of digital temperature measurement circuit, comprise thermistor, reference resistance, discharge circuit, electric capacity and microprocessor, the one I/O mouth order series thermal-sensitive resistance and the described electric capacity of microprocessor are formed first charge circuit, connect in proper order reference resistance and described electric capacity of the 2nd I/O mouth of microprocessor is formed second charge circuit, and the 3rd I/O mouth order discharged in series circuit and the described electric capacity of microprocessor are formed discharge loop.
Described discharge circuit can be realized with discharge resistance simply.
The resistance of described discharge resistance can be preferred 100～300 ohm.
The utility model adopts technique scheme, and its beneficial technical effects is: 1) only need to adopt the primary element of minute quantity simply to be connected with microprocessor, and simple in structure; 2) do not use the A/D analog to digital converter can carry out the digital measurement of temperature, with low cost.
[description of drawings]
Below by embodiment also in conjunction with the accompanying drawings, the utility model is described in further detail:
Fig. 1 is the circuit diagram of the utility model numeral temperature measurement circuit.
Fig. 2 is the circuit diagram of a kind of preferred version of digital temperature measurement circuit among Fig. 1.
[embodiment]
Embodiment one, a kind of digital temperature measurement circuit, in conjunction with Fig. 1 and Fig. 2, comprise thermistor Rntc, reference resistance Rref, discharge resistance R1, capacitor C 1 and microprocessor as discharge circuit, one end of thermistor, reference resistance and discharge resistance connects I/Ontc, I/Oref and three I/O mouths of I/Otest of microprocessor respectively, and other end parallel connection is after capacitor C 1 earthing potential.
The concrete course of work:
(1) microprocessor is made as low level output with the I/Otest mouth, and other mouthful is made as input, promptly by discharge resistance R1 capacitor C 1 is discharged, and time-delay is until having put;
(2) microprocessor is made as high level output with the I/Oref mouth, and other mouthful is made as input, promptly by reference resistance Rref capacitor C 1 charged.Simultaneously, the zero clearing of microprocessor internal timer also picks up counting, and when detecting the I/Otest mouth and be high level, illustrates that capacitor C 1 has been full of, stops timing, and timer is noted Rref from beginning to be charged to the time T ref that charging finishes.
(3) repeat (1);
(4) microprocessor is made as high level output with the I/Ontc mouth, and other mouthful is made as input, promptly by thermistor Rntc capacitor C 1 charged.Simultaneously, the zero clearing of microprocessor internal timer also picks up counting, and when detecting the I/Otest mouth and be high level, illustrates that capacitor C 1 has been full of, stops timing, and timer is noted reference resistance Rntc from beginning to be charged to the time T ntc that charging finishes.
(5) owing to be that same electric capacity is charged in step (2) and (4), microprocessor can utilize formula Rntc=Tntc*Rref/Tref that the data of being gathered are carried out multiplication and division and handle, and calculates a resistance of thermistor.
(6) microprocessor repeats the resistance that a plurality of (being generally about 8) thermistor is gathered in above-mentioned steps (1)～(5), calculates its mean value.
(7) the microprocessor relevant temperature value of tabling look-up and drawing its induction according to the mean value of thermistor.
According to the above-mentioned course of work as can be seen, the error of the utility model temperature measurement circuit mainly comes from: the precision of the precision of timer of microprocessor, reference resistance Rref and the precision of thermistor Rntc, and irrelevant with the output voltage values of microprocessor, threshold voltage, electric capacity precision etc.Therefore, suitably choose the precision of thermistor and reference resistance, and make the frequency of operation of microprocessor enough high, just can obtain temperature measurement accuracy preferably.
Discharge resistance R1 generally selects 200 ohm for use.Discharge circuit in this example also can adopt other combination of elements forms, as long as can fast and effeciently discharge to capacitor C 1.
Claims (3)
1, a kind of digital temperature measurement circuit, comprise thermistor and microprocessor, it is characterized in that: also comprise electric capacity, reference resistance and discharge circuit, the one I/O mouth order series thermal-sensitive resistance and the described electric capacity of microprocessor are formed first charge circuit, connect in proper order reference resistance and described electric capacity of the 2nd I/O mouth of microprocessor is formed second charge circuit, and the 3rd I/O mouth order discharged in series circuit and the described electric capacity of microprocessor are formed discharge loop.
2, digital temperature measurement circuit according to claim 1, it is characterized in that: described discharge circuit is a discharge resistance.
3, digital temperature measurement circuit according to claim 2 is characterized in that: the resistance of described discharge resistance is 100～300 ohm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420061227 CN2725866Y (en) | 2004-09-08 | 2004-09-08 | Digital temp measuring circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420061227 CN2725866Y (en) | 2004-09-08 | 2004-09-08 | Digital temp measuring circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2725866Y true CN2725866Y (en) | 2005-09-14 |
Family
ID=35040582
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200420061227 Expired - Fee Related CN2725866Y (en) | 2004-09-08 | 2004-09-08 | Digital temp measuring circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2725866Y (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104501991A (en) * | 2014-12-10 | 2015-04-08 | 广东美的制冷设备有限公司 | Remote controller, temperature sampling device and temperature sampling control method |
| CN105547514A (en) * | 2016-01-25 | 2016-05-04 | 四川长虹电器股份有限公司 | Temperature measurement circuit and method |
| CN105698957A (en) * | 2016-03-21 | 2016-06-22 | 四川长虹电器股份有限公司 | Temperature measuring circuit and method |
| CN109374148A (en) * | 2018-11-26 | 2019-02-22 | 山东航天电子技术研究所 | A kind of temperature measuring device and measurement method |
-
2004
- 2004-09-08 CN CN 200420061227 patent/CN2725866Y/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104501991A (en) * | 2014-12-10 | 2015-04-08 | 广东美的制冷设备有限公司 | Remote controller, temperature sampling device and temperature sampling control method |
| CN104501991B (en) * | 2014-12-10 | 2018-05-29 | 广东美的制冷设备有限公司 | Remote controler, temperature sampling device and temperature sampling control method |
| CN105547514A (en) * | 2016-01-25 | 2016-05-04 | 四川长虹电器股份有限公司 | Temperature measurement circuit and method |
| CN105698957A (en) * | 2016-03-21 | 2016-06-22 | 四川长虹电器股份有限公司 | Temperature measuring circuit and method |
| CN109374148A (en) * | 2018-11-26 | 2019-02-22 | 山东航天电子技术研究所 | A kind of temperature measuring device and measurement method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101551264B (en) | Capacitance electronic type fuel sensor | |
| CN103575340B (en) | Liquid flow non-magnetic detector and detection method thereof | |
| CN106645981A (en) | Capacitance measuring circuit for capacitor | |
| CN101308172A (en) | Current integration -type power detection device and power checking module | |
| CN101118190A (en) | Temperature measurement device and process for measuring temperature with device | |
| CN102253286A (en) | Resistance/capacitance measuring method and device thereof | |
| CN201845051U (en) | Three-phase intelligent electric energy meter | |
| CN2725866Y (en) | Digital temp measuring circuit | |
| CN107422268B (en) | Battery dump energy detection method | |
| CN110375876A (en) | A kind of IGBT temperature detection circuit and method | |
| CN201215570Y (en) | Voltage detecting circuit for battery | |
| CN201811809U (en) | Temperature detection circuit | |
| CN202166693U (en) | Resistance and capacitance measuring device | |
| CN102768078A (en) | Automatic resistance compensation method for temperature-measuring conductors for two-wire thermal resistor | |
| CN206019785U (en) | Liquid level detection circuit and wall-breaking machine | |
| CN202794284U (en) | Multifunctional intelligent electric power meter | |
| CN208272954U (en) | A kind of conversion circuit of voltage to the time | |
| CN202068387U (en) | RC oscillator circuit for capacitance type touch press key | |
| CN106017717B (en) | Thermistor temperature sensor | |
| CN104483580B (en) | A kind of DC DC transducers zero load detection means based on PFM step-by-step countings | |
| CN202033125U (en) | Low cost high precision temperature-measuring circuit used in calorimeter | |
| CN2365677Y (en) | Apparatus for measuring resistance quantity with one chip machine | |
| CN204422094U (en) | Temperature measurement circuit and electromagnetic oven | |
| CN201508209U (en) | Capacitance electronic fuel sensor | |
| CN202230132U (en) | Power consumption calculating circuit and air conditioner comprising the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C56 | Change in the name or address of the patentee |
Owner name: SHENZHEN AND INTELLIGENT CONTROL AND THAILAND CO. Free format text: FORMER NAME OR ADDRESS: HEERTAI ELECTRONIC SCI-TECH CO., LTD. SHENZHEN |
|
| CP03 | Change of name, title or address |
Address after: D building, block ten, Institute of international technology innovation, South ten road, hi tech Zone, Guangdong, Shenzhen, China: 518057 Patentee after: ShenZhen H&T Intelligent Control CO., LTD. Address before: D building, block ten, Institute of international technology innovation, South ten road, hi tech Zone, Guangdong, Shenzhen, China: 518057 Patentee before: Heertai Electronic Sci. & Tech. Co., Ltd., Shenzhen City |
|
| DD01 | Delivery of document by public notice |
Addressee: ShenZhen H&T Intelligent Control CO., LTD. Zheng Qingling Document name: Notification to Pay the Fees |
|
| DD01 | Delivery of document by public notice |
Addressee: Shenzhen heertai intelligent control Limited by Share Ltd Zheng Qingling Document name: Notification of Termination of Patent Right |
|
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20050914 Termination date: 20110908 |