CN109297553A - MEMS heat membrane type flow sensor constant temperature difference control circuit - Google Patents
MEMS heat membrane type flow sensor constant temperature difference control circuit Download PDFInfo
- Publication number
- CN109297553A CN109297553A CN201811359379.XA CN201811359379A CN109297553A CN 109297553 A CN109297553 A CN 109297553A CN 201811359379 A CN201811359379 A CN 201811359379A CN 109297553 A CN109297553 A CN 109297553A
- Authority
- CN
- China
- Prior art keywords
- temperature
- constant
- temperature detection
- detection resistance
- 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.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
- G01F1/684—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
- G01F1/6845—Micromachined devices
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
- G01F1/684—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
- G01F1/688—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow using a particular type of heating, cooling or sensing element
- G01F1/69—Structural arrangements; Mounting of elements, e.g. in relation to fluid flow using a particular type of heating, cooling or sensing element of resistive type
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
- G01F1/696—Circuits therefor, e.g. constant-current flow meters
- G01F1/698—Feedback or rebalancing circuits, e.g. self heated constant temperature flowmeters
- G01F1/699—Feedback or rebalancing circuits, e.g. self heated constant temperature flowmeters by control of a separate heating or cooling element
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Volume Flow (AREA)
Abstract
The present invention provides a kind of MEMS heat membrane type flow sensor constant temperature difference control circuits, belong to flow sensor technical field, the circuit includes: the first temperature detection resistance, second temperature detection resistance, adding thermal resistance, closed-loop feedback circuit, the first constant-current source, the second constant-current source；First temperature detection resistance is arranged at the air inlet of sensor, and adding thermal resistance and second temperature detection resistance are disposed adjacent at the middle part of sensor；First constant-current source is connect with one end of the first temperature detection resistance, and the second constant-current source is connect with one end of second temperature detection resistance；First connects end altogether of the first constant-current source and the first temperature detection resistance accesses the first input end of closed-loop feedback circuit, the second input terminal of the second constant-current source and the second connects end altogether access closed-loop feedback circuit of second temperature detection resistance；The output end of closed-loop feedback circuit is connect with adding thermal resistance, can accurately guarantee that sensor intake air temperature and Heating Zone Temperature difference Δ T are constant.
Description
Technical field
The invention belongs to flow sensor technical fields, are to be related to a kind of MEMS hot diaphragm type flow sensing more specifically
Device constant temperature difference control circuit.
Background technique
" thermal discharge of fluid or the quality of caloric receptivity and the fluid that MEMS heat membrane type flow sensor is proposed with Thomas
Flow is directly proportional " theory based on, using heat source to sensor sensing element heat, when gas flow into when forced convection occurs
Heat transmitting, makes Sensitive Apparatus temperature field change, there are certain functional relations between change of temperature field amount and gas, with this
To measure gas flow values.
It is illustrated with reference to the typical structure that Fig. 1, Fig. 1 are MEMS heat membrane type flow sensor, is adding thermal resistance 3 among sensor
And the temperature detection resistance 4 of adding thermal resistance, 3 upstream and downstream of adding thermal resistance it is symmetrical flow detection resistance 2, the resistance be positive temperature
The thermistor of coefficient is spent, air inlet is that temperature adds measuring resistance 1.The measuring principle of the sensor are as follows: adding thermal resistance 3, which is powered, to be formed
Heating zone, the temperature of heating zone are 60~110 DEG C higher than environment temperature.When there is no gas to flow through, temperature field above and below the resistance of heating zone
It is symmetrical, as shown by the solid line in the drawings；When there is gas to flow through, change of temperature field is dashed lines states in figure, and air-flow leads to upstream
Detection resistance temperature reduces, and resistance reduces, while the heat of hot zone is downstream electric so as to cause the detection in downstream by air-flow band
It hinders temperature to increase, resistance increases.Intake air temperature remains constant with Heating Zone Temperature difference Δ T, i.e., working sensor is in constant temperature
Differential mode formula, then upstream and downstream detection resistance generates temperature difference Δ T1 and changes with gas flow and change, the upstream and downstream inspection in sensor
Measuring resistance constitutes Wheatstone bridge, and difference signals Δ T1 caused by gas flow is changed into voltage signal.Therefore one is needed
Kind can accurately guarantee sensor intake air temperature and Heating Zone Temperature difference Δ T constant control circuit.
Summary of the invention
The purpose of the present invention is to provide a kind of MEMS heat membrane type flow sensor constant temperature difference control circuits, can be realized essence
Ensure to demonstrate,prove sensor intake air temperature and Heating Zone Temperature difference Δ T constant control circuit.
In a first aspect, to achieve the above object, the technical solution adopted by the present invention is that: a kind of MEMS hot diaphragm type flow is provided
Sensor constant temperature difference control circuit, comprising: the first temperature detection resistance, second temperature detection resistance, adding thermal resistance, closed loop feedback
Circuit, the first constant-current source, the second constant-current source；
First temperature detection resistance is arranged at the air inlet of sensor, the adding thermal resistance and the second temperature
Detection resistance is disposed adjacent at the middle part of the sensor；
First constant-current source is connect with one end of first temperature detection resistance, second constant-current source and described the
One end of two temperature detection resistances connects；
First connects end altogether of first constant-current source and first temperature detection resistance accesses the closed-loop feedback circuit
First input end, the second connects end altogether of second constant-current source and the second temperature detection resistance accesses the closed loop feedback
Second input terminal of circuit；The output end of the closed-loop feedback circuit is connect with the adding thermal resistance.
Further, the closed-loop feedback circuit includes: difference amplifier and triode；
The non-inverting input terminal of the difference amplifier is the first input end of the closed-loop feedback circuit, the differential amplification
The reverse input end of device is the second input terminal of the closed-loop feedback circuit, the output end of the difference amplifier and three pole
The base stage of pipe connects, the output end of the extremely described closed-loop feedback circuit of the triode emission.
Further, the other end ground connection of first temperature detection resistance.
Further, the other end ground connection of the second temperature detection resistance.
Further, the resistance value R of first temperature detection resistance1=R1-0+k1T1, wherein R1-0For the first temperature detection
Resistance value at 0 DEG C of resistance, k1For the temperature system of the first temperature detection resistance, T1For sensor air inlet temperature.
Further, the resistance value R of the second temperature detection resistance4=R4-0+k4T2, wherein R4-0For second temperature detection
Resistance value at 0 DEG C of resistance, k4For the temperature system of second temperature detection resistance, T2For sensor Heating Zone Temperature.
Further, first constant current source current is I1, second constant current source current is I2, the R1-0、R4-0、k1
And k4Meet relationship:
R1I1-R4I2=R1-0I1+k1T1I1-R4-0I2-k4T2I2=0, wherein T2-T1=Δ T, Δ T are at sensor air inlet
It is poor with the steady temperature of heating zone.
Further, the circuit further includes analog-to-digital conversion device and filter；The input terminal of the analog-to-digital conversion device and institute
The first input end connection of closed-loop feedback circuit is stated, the output end of the analog-to-digital conversion device is connect with the filter, the filter
The digital signal of the output end output of wave device is used for the temperature-compensating of rear class sensor.
Second aspect, the embodiment of the present invention also provides a kind of MEMS heat membrane type flow sensor, including asic chip, described
Asic chip is equipped with MEMS heat membrane type flow sensor constant temperature difference control circuit as described in relation to the first aspect.
The beneficial effect of MEMS heat membrane type flow sensor constant temperature difference control circuit provided by the invention is: with existing skill
Art is compared, MEMS heat membrane type flow sensor constant temperature difference control circuit of the present invention, the first temperature detection resistance and second temperature inspection
Measuring resistance distinguishes two constant-current sources, and electric current is constant, the temperature hair of temperature and adding thermal resistance heating zone at sensor air inlet
When changing, the resistance value of the first temperature detection resistance and second temperature detection resistance changes, and is input to closed-loop feedback circuit
First input end and the second input terminal voltage change, two voltage differences are by closed-loop feedback circuit enhanced processing and feed back to
Adding thermal resistance makes the difference of the temperature at sensor air inlet and the temperature of adding thermal resistance heating zone by controlling adding thermal resistance
It is constant.
Detailed description of the invention
It to describe the technical solutions in the embodiments of the present invention more clearly, below will be to embodiment or description of the prior art
Needed in attached drawing be briefly described, it should be apparent that, the accompanying drawings in the following description is only of the invention some
Embodiment for those of ordinary skill in the art without creative efforts, can also be attached according to these
Figure obtains other attached drawings.
Fig. 1 is the structural schematic diagram of MEMS heat membrane type flow sensor provided in an embodiment of the present invention；
Fig. 2 is the schematic diagram for the MEMS heat membrane type flow sensor constant temperature difference control circuit that one embodiment of the invention provides；
Fig. 3 be another embodiment of the present invention provides MEMS heat membrane type flow sensor constant temperature difference control circuit signal
Figure.
Wherein, each appended drawing reference in figure:
First temperature detection resistance -100, second temperature detection resistance -200, adding thermal resistance -300, closed-loop feedback circuit -
400, the first constant-current source -500, the second constant-current source -600, difference amplifier -410, triode -420, analog-to-digital conversion device -700, filter
Wave device -800.
Specific embodiment
In order to which technical problems, technical solutions and advantages to be solved are more clearly understood, tie below
Accompanying drawings and embodiments are closed, the present invention will be described in further detail.It should be appreciated that specific embodiment described herein is only
To explain the present invention, it is not intended to limit the present invention.
Also referring to Fig. 1 and Fig. 2, now to MEMS heat membrane type flow sensor constant temperature difference control circuit provided by the invention
It is illustrated.The MEMS heat membrane type flow sensor constant temperature difference control circuit, comprising: the first temperature detection resistance 100, second
Temperature detection resistance 200, adding thermal resistance 300, closed-loop feedback circuit 400, the first constant-current source 500, the second constant-current source 600.
First temperature detection resistance 100 is arranged at the air inlet of sensor (in Fig. 1 shown in 1), the heating electricity
Resistance 300 and the second temperature detection resistance 200 are disposed adjacent at the middle part of the sensor (in Fig. 1 shown in 3,4)；
First constant-current source 500 is connect with one end of 100 resistance of the first temperature detection electricity, second constant-current source
600 connect with one end of the second temperature detection resistance 200；
It is anti-that first connects end altogether of first constant-current source 500 and first temperature detection resistance 100 accesses the closed loop
The first input end 401 of current feed circuit 400, second constant-current source 600 connect altogether with the second of the second temperature detection resistance 200
Terminate the second input terminal 402 into the closed-loop feedback circuit 400；The output end 403 of the closed-loop feedback circuit 400 with it is described
Adding thermal resistance 300 connects.
In the present embodiment, the first temperature detection resistance 100, second temperature detection resistance 200 are temperature-sensitive resistor.
First temperature detection resistance 100 is passed for the temperature at measurement sensor air inlet, second temperature detection resistance 200 for measuring
The temperature of 300 heating zone of adding thermal resistance of sensor.
As can be seen from the above description, the first temperature detection resistance and second temperature detection resistance distinguish two constant-current sources, electric current
It is constant, when the temperature of temperature and adding thermal resistance heating zone at sensor air inlet changes, the first temperature detection resistance
It changes with the resistance value of second temperature detection resistance, is input to the first input end and second input terminal of closed-loop feedback circuit
Voltage change, two voltage differences are by closed-loop feedback circuit enhanced processing and feed back to adding thermal resistance, by controlling adding thermal resistance
So that the difference of the temperature of temperature and adding thermal resistance heating zone at sensor air inlet is constant.
Further, referring to Fig. 2, as MEMS heat membrane type flow sensor constant temperature difference control circuit provided by the invention
A kind of specific embodiment, the closed-loop feedback circuit 400 includes: difference amplifier 410 and triode 420；
The non-inverting input terminal of the difference amplifier 410 is the first input end of the closed-loop feedback circuit, the difference
The reverse input end of amplifier 420 is the second input terminal of the closed-loop feedback circuit, the output end of the difference amplifier 410
It is connect with the base stage of the triode 420, the triode 420 emits the output end of the extremely described closed-loop feedback circuit.
As can be seen from the above description, realizing amplification and feedback to voltage difference, structure by difference amplifier and triode
Simply, at low cost.
Further, with reference to Fig. 2, the other end of first temperature detection resistance 100 is grounded.The second temperature detection
The other end of resistance 200 is grounded.One end closed-loop feedback circuit 400 of the adding thermal resistance 300 connects, other end ground connection.
Further, the resistance value R of first temperature detection resistance1=R1-0+k1T1, wherein R1-0For the first temperature detection
Resistance value at 0 DEG C of resistance, k1For the temperature system of the first temperature detection resistance, T1For sensor air inlet temperature.
The resistance value R of the second temperature detection resistance4=R4-0+k4T2, wherein R4-0When being 0 DEG C of second temperature detection resistance
Resistance value, k4For the temperature system of second temperature detection resistance, T2For sensor Heating Zone Temperature.
First constant current source current is I1, second constant current source current is I2, the R1-0、R4-0、k1And k4Meet and closes
System:
R1I1-R4I2=R1-0I1+k1T1I1-R4-0I2-k4T2I2=0, wherein T2-T1=Δ T, Δ T are at sensor air inlet
It is poor with the steady temperature of heating zone.
As can be seen from the above description, by rationally designing R1-0、R4-0、k1And k4, that is, can guarantee at sensor air inlet and heat
The steady temperature in area is poor.
Further, referring to figs. 2 and 3, it is controlled as MEMS heat membrane type flow sensor constant difference provided by the invention
A kind of specific embodiment of circuit, the MEMS heat membrane type flow sensor constant temperature difference control circuit further include: analog-to-digital conversion
Device 700 and filter 800.The first input end of the input terminal of the analog-to-digital conversion device 800 and the closed-loop feedback circuit 400 connects
It connects, the output end of the analog-to-digital conversion device 700 is connect with the filter 800, the number of the output end output of the filter 800
Word signal is used for the temperature-compensating of rear class sensor.
In the present embodiment, analog-to-digital conversion device 700 is second order Σ Δ analog-digital converter, realizes signal conversion.
In the present embodiment, filter 800 is low-pass filter, such as cic filter+iir filter, realizes drop respectively
Sampling, so that the effect that output data quantity reduces and high-frequency noise filters out.
Second aspect, the embodiment of the present invention also provides a kind of MEMS heat membrane type flow sensor, including asic chip, described
Asic chip is equipped with such as above-mentioned MEMS heat membrane type flow sensor constant temperature difference control circuit.
In the present embodiment, asic chip is the asic chip of 0.18 μm of technique manufacture, has the characteristics that minimize integrated form.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention
Made any modifications, equivalent replacements, and improvements etc., should all be included in the protection scope of the present invention within mind and principle.
Claims (9)
1. a kind of MEMS heat membrane type flow sensor constant temperature difference control circuit characterized by comprising the first temperature detection electricity
Resistance, second temperature detection resistance, adding thermal resistance, closed-loop feedback circuit, the first constant-current source, the second constant-current source；
First temperature detection resistance is arranged at the air inlet of sensor, the adding thermal resistance and second temperature detection
Resistance is disposed adjacent at the middle part of the sensor；
First constant-current source is connect with one end of first temperature detection resistance, second constant-current source and second temperature
Spend one end connection of detection resistance；
First connects end altogether of first constant-current source and first temperature detection resistance accesses the of the closed-loop feedback circuit
Second connects end altogether of one input terminal, second constant-current source and the second temperature detection resistance accesses the closed-loop feedback circuit
The second input terminal；The output end of the closed-loop feedback circuit is connect with the adding thermal resistance.
2. MEMS heat membrane type flow sensor constant temperature difference control circuit as described in claim 1, which is characterized in that the closed loop
Feed circuit includes: difference amplifier and triode；
The non-inverting input terminal of the difference amplifier is the first input end of the closed-loop feedback circuit, the difference amplifier
Reverse input end is the second input terminal of the closed-loop feedback circuit, the output end of the difference amplifier and the triode
Base stage connection, the output end of the extremely described closed-loop feedback circuit of the triode emission.
3. MEMS heat membrane type flow sensor constant temperature difference control circuit as described in claim 1, which is characterized in that described first
The other end of temperature detection resistance is grounded.
4. MEMS heat membrane type flow sensor constant temperature difference control circuit as described in claim 1, which is characterized in that described second
The other end of temperature detection resistance is grounded.
5. MEMS heat membrane type flow sensor constant temperature difference control circuit as described in claim 1, which is characterized in that described first
The resistance value R of temperature detection resistance1=R1-0+k1T1, wherein R1-0Resistance value when being 0 DEG C of the first temperature detection resistance, k1For the first temperature
Spend the temperature system of detection resistance, T1For sensor air inlet temperature.
6. MEMS heat membrane type flow sensor constant temperature difference control circuit as claimed in claim 5, which is characterized in that described second
The resistance value R of temperature detection resistance4=R4-0+k4T2, wherein R4-0Resistance value when being 0 DEG C of second temperature detection resistance, k4For the second temperature
Spend the temperature system of detection resistance, T2For sensor Heating Zone Temperature.
7. MEMS heat membrane type flow sensor constant temperature difference control circuit as claimed in claim 6, which is characterized in that described first
Constant current source current is I1, second constant current source current is I2, the R1-0、R4-0、k1And k4Meet relationship:
R1I1-R4I2=R1-0I1+k1T1I1-R4-0I2-k4T2I2=0, wherein T2-T1=Δ T, Δ T are at sensor air inlet and to add
The steady temperature of hot-zone is poor.
8. MEMS heat membrane type flow sensor constant temperature difference control circuit as described in any one of claim 1 to 7, feature exist
In further including analog-to-digital conversion device and filter；The first of the input terminal of the analog-to-digital conversion device and the closed-loop feedback circuit is defeated
Enter end connection, the output end of the analog-to-digital conversion device is connect with the filter, the number of the output end output of the filter
Signal is used for the temperature-compensating of rear class sensor.
9. a kind of MEMS heat membrane type flow sensor, which is characterized in that including asic chip, the asic chip is equipped with as weighed
Benefit requires 1 to 8 described in any item MEMS heat membrane type flow sensor constant temperature difference control circuits.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811359379.XA CN109297553B (en) | 2018-11-15 | 2018-11-15 | Constant temperature difference control circuit of MEMS hot film type flow sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811359379.XA CN109297553B (en) | 2018-11-15 | 2018-11-15 | Constant temperature difference control circuit of MEMS hot film type flow sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109297553A true CN109297553A (en) | 2019-02-01 |
| CN109297553B CN109297553B (en) | 2020-07-07 |
Family
ID=65143422
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811359379.XA Active CN109297553B (en) | 2018-11-15 | 2018-11-15 | Constant temperature difference control circuit of MEMS hot film type flow sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109297553B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110274649A (en) * | 2019-06-13 | 2019-09-24 | 武汉大学 | A kind of hot temperature difference type flow sensor and preparation method thereof based on MEMS technology |
| CN111323090A (en) * | 2020-03-02 | 2020-06-23 | 深圳大学 | Micro flow sensor based on thermal feedback, airflow measuring system and measuring method |
| CN112730886A (en) * | 2020-12-21 | 2021-04-30 | 上海交通大学 | Flexible MEMS flow velocity sensor based on amorphous germanium thermal resistor |
| CN113157008A (en) * | 2021-04-01 | 2021-07-23 | 青岛芯笙微纳电子科技有限公司 | MEMS mass flow controller and control method |
| CN113670452A (en) * | 2021-08-18 | 2021-11-19 | 深圳市汇顶科技股份有限公司 | Non-contact temperature measuring device, temperature measuring module therein and electronic equipment |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6432120A (en) * | 1987-07-29 | 1989-02-02 | Sharp Kk | Flow sensor |
| CN1197200A (en) * | 1997-01-16 | 1998-10-28 | 株式会社日立制作所 | Measuring element and mass air flow meter therewith |
| US20020178807A1 (en) * | 2001-06-05 | 2002-12-05 | Mitsubishi Denki Kabushiki Kaisha | Thermosensitive flow rate detecting device |
| JP2003279395A (en) * | 2002-03-20 | 2003-10-02 | Mitsui Mining & Smelting Co Ltd | Flow rate measuring method and flowmeter |
| CN101680788A (en) * | 2007-05-24 | 2010-03-24 | 株式会社山武 | Heat flowmeter |
| CN102141422A (en) * | 2010-12-31 | 2011-08-03 | 北京航空航天大学 | Flow-temperature integrated measurement device for moonlet single-phase fluid thermal control loop |
-
2018
- 2018-11-15 CN CN201811359379.XA patent/CN109297553B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6432120A (en) * | 1987-07-29 | 1989-02-02 | Sharp Kk | Flow sensor |
| CN1197200A (en) * | 1997-01-16 | 1998-10-28 | 株式会社日立制作所 | Measuring element and mass air flow meter therewith |
| US20020178807A1 (en) * | 2001-06-05 | 2002-12-05 | Mitsubishi Denki Kabushiki Kaisha | Thermosensitive flow rate detecting device |
| JP2003279395A (en) * | 2002-03-20 | 2003-10-02 | Mitsui Mining & Smelting Co Ltd | Flow rate measuring method and flowmeter |
| CN101680788A (en) * | 2007-05-24 | 2010-03-24 | 株式会社山武 | Heat flowmeter |
| CN102141422A (en) * | 2010-12-31 | 2011-08-03 | 北京航空航天大学 | Flow-temperature integrated measurement device for moonlet single-phase fluid thermal control loop |
Non-Patent Citations (1)
| Title |
|---|
| 袁琨翔: "热式流量计的误差分析及精度提升方法研究", 《中国游戏硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110274649A (en) * | 2019-06-13 | 2019-09-24 | 武汉大学 | A kind of hot temperature difference type flow sensor and preparation method thereof based on MEMS technology |
| CN110274649B (en) * | 2019-06-13 | 2020-09-01 | 武汉大学 | A kind of thermal temperature difference flow sensor based on MEMS technology and preparation method thereof |
| CN111323090A (en) * | 2020-03-02 | 2020-06-23 | 深圳大学 | Micro flow sensor based on thermal feedback, airflow measuring system and measuring method |
| CN111323090B (en) * | 2020-03-02 | 2021-12-14 | 深圳大学 | Micro flow sensor based on thermal feedback, airflow measuring system and measuring method |
| CN112730886A (en) * | 2020-12-21 | 2021-04-30 | 上海交通大学 | Flexible MEMS flow velocity sensor based on amorphous germanium thermal resistor |
| CN113157008A (en) * | 2021-04-01 | 2021-07-23 | 青岛芯笙微纳电子科技有限公司 | MEMS mass flow controller and control method |
| CN113157008B (en) * | 2021-04-01 | 2022-08-23 | 青岛芯笙微纳电子科技有限公司 | MEMS mass flow controller and control method |
| CN113670452A (en) * | 2021-08-18 | 2021-11-19 | 深圳市汇顶科技股份有限公司 | Non-contact temperature measuring device, temperature measuring module therein and electronic equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109297553B (en) | 2020-07-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109297553A (en) | MEMS heat membrane type flow sensor constant temperature difference control circuit | |
| EP2256466B1 (en) | Multi-dynamic-range sensor and method | |
| JP2704048B2 (en) | Current difference type thermal mass flow transducer | |
| JPWO2013105124A1 (en) | Flow measuring device | |
| JP6073489B2 (en) | Air mass flow meter with sensor element | |
| US9207109B2 (en) | Flow sensor with improved linear output | |
| EP3121566A1 (en) | A mems airflow sensor die incorporating additional circuitry on the die | |
| US7185538B2 (en) | Methods and systems for sensing air vehicle airspeed | |
| JP5680178B1 (en) | Flow sensor and control system for internal combustion engine | |
| KR900005880B1 (en) | Thermo-water meter | |
| CN105910662A (en) | Hot air flow transmitter with environment temperature compensation function | |
| US5522261A (en) | Fluid flow direction and velocity monitor and temperature compensating circuit therefor | |
| WO2024221799A1 (en) | Gas flow sensor chip and gas flow sensor | |
| CN201060013Y (en) | Heat membrane type air mass flow sensor | |
| CN115420395A (en) | Temperature transmitting circuit | |
| JP2010190715A (en) | Air flow rate measuring apparatus | |
| CN112729427A (en) | Thermal differential pressure flow sensor | |
| CN103712659A (en) | Hot type air flow meter | |
| CN117686043B (en) | Thermal type gas flow compensation calculation method and thermal type gas flow sensor | |
| JP3675721B2 (en) | Thermal air flow meter | |
| JPS5826346Y2 (en) | Karman vortex flow meter or current meter | |
| JPS59136619A (en) | Vortex flowmeter | |
| CN112444297A (en) | Working circuit for hot wire type air flow sensor and sensor thereof | |
| JP2003315129A (en) | Thermal flow meter | |
| JPH08105779A (en) | Thermal-type air flow-rate detector |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |