CN106873702A - A kind of compensation circuit of piezoresistive pressure sensor - Google Patents
A kind of compensation circuit of piezoresistive pressure sensor Download PDFInfo
- Publication number
- CN106873702A CN106873702A CN201510913166.7A CN201510913166A CN106873702A CN 106873702 A CN106873702 A CN 106873702A CN 201510913166 A CN201510913166 A CN 201510913166A CN 106873702 A CN106873702 A CN 106873702A
- Authority
- CN
- China
- Prior art keywords
- circuit
- compensation
- pressure sensor
- piezoresistive pressure
- compensation circuit
- 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.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
- G05F1/00—Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
- G05F1/10—Regulating voltage or current
- G05F1/46—Regulating voltage or current wherein the variable actually regulated by the final control device is dc
- G05F1/56—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices
- G05F1/565—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices sensing a condition of the system or its load in addition to means responsive to deviations in the output of the system, e.g. current, voltage, power factor
- G05F1/567—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices sensing a condition of the system or its load in addition to means responsive to deviations in the output of the system, e.g. current, voltage, power factor for temperature compensation
Abstract
A kind of compensation circuit of piezoresistive pressure sensor, using the static application of digital analog converter, as control circuit come the effect instead of trimming resistance in conventional compensation approach.Using DAC and memory is in analog channel process signal and instead of the function of trimming resistance, the adjustment amount that DAC is produced is aided with some functional circuits to compensate sensor signal.To make sensor output signal more linearize and gain the two targets can be adjusted in circuit, the primary structure of signal compensation circuit includes offset generating circuit, band-gap reference circuit, preamplifier OP1, output amplifier OP2, full range regulation and full scale tc compensation core circuit, DAC1, DAC2, zero temperature compensating coefficient core circuit.Circuit working stability, simple to operate, high precision, cost are relatively low, and adaptability is good, overcome the shortcoming that conventional compensation device is expensive, service efficiency is low, complex operation, precision be not high.
Description
Art
The present invention relates to a kind of compensation circuit of piezoresistive pressure sensor, it is adaptable to sensor field.
Background technology
Sensor technology is a kind of high-tech technology that is attractive in advanced information society, quickly growing, is the key for obtaining science and technology of information acquisition.Sensor is converted to the tested nature information for needing by certain linear scale by certain rule and can be used in the measurable signal that digital signal processor or single-chip microcomputer etc. are processed as the window between the physical quantity and electric signal of connection nature.Sensor, as the main shaft in measuring system, is that system is able to the accurate key element for completing measurement and process task.And in recent decades, development and the information processing and the development of transmission technology of the detection technique of sensor are seriously mismatched, so that the difficult point as Information Technology Development.Therefore, sensor is the principal element for promoting a large amount of technical research personnel constantly to assault fortified position in this key position of information-intensive society.
The piezoresistive pressure sensor being fabricated by using the piezoresistive effect principle of silicon materials, by development for many years a, it has also become visual plant that detection is provided for aspects such as industry and medical treatment.Piezoresistive pressure sensor compares with pressure sensor more traditional before, it has, and high precision, sensitivity are high, dynamic response is fast, good stability, small size, low cost the features such as.But because the temperature characterisitic of silicon materials can have a huge impact to the sensitivity of sensor and certainty of measurement, so, it is an important topic for meriting attention to carry out temperature-compensating to the output signal of piezoresistive pressure sensor.Its compensation circuit is general by PTAT, current source, amplifying circuit and laser trimming resistance composition.These compensation ways more tradition and simple, traditional sensor compensation, mainly concentrate in the compensation of zero point and temperature drift.The null offset of sensor can be by the serial or parallel connection temperature-sensing element (device) on Wheatstone bridge (such as：Thermistor, diode) method solve.Had similar to following shortcoming using the raw compensation method of this principle：Laser trimming resistance equipment is expensive, service efficiency is low, complex operation, precision be not high and compensation resistance be not yet do not produced in temperature change drift etc..Therefore a kind of working stability, simple to operate, high precision, lower-cost compensation circuit are designed necessary.
The content of the invention
The present invention provides a kind of compensation circuit of piezoresistive pressure sensor, and circuit working stability, simple to operate, high precision, cost are relatively low, and adaptability is good, overcomes the shortcoming that conventional compensation device is expensive, service efficiency is low, complex operation, precision be not high.
The technical solution adopted in the present invention is：
This circuit is using the static application of digital analog converter, as control circuit come the effect instead of trimming resistance in conventional compensation approach.Using DAC and memory is in analog channel process signal and instead of the function of trimming resistance, the adjustment amount that DAC is produced is aided with some functional circuits to compensate sensor signal.To make sensor output signal more linearize and can adjust gain the two targets in circuit, the signal after the thermal compensation signal produced with DAC after can sensor primary output signal be amplified be added feed back to preamplifier.
The primary structure of signal compensation circuit includes offset generating circuit, band-gap reference circuit, preamplifier OP1, output amplifier OP2, full range regulation and full scale tc compensation core circuit, DAC1, DAC2, zero temperature compensating coefficient core circuit.
The band-gap reference source circuit is changed on the basis of Widlar band-gap references and formed.In mains fluctuations, the part of increased Q3, Q5 and Q6 causes output voltage stabilization by a feedback loop.
The effect of the bias voltage circuit is to provide suitable bias voltage or electric current to modules such as each amplifier herein, digital analog converter and temperature-compensation circuits, and makes the stable working state of circuit.Rl, R2, Q1 and Q2 constitute Widlar current sources (micro-current source) circuit, and contacted a resistance R2 on Q2 emitter stages, if R2 ≠ 0, Ql and Q2 is operated under the different emitter voltages of base stage one.Q3, Q4, Q5, R3, R4 and R5 constitute a current source on the basis of VBE, in order that there is electric current to flow through in Q5, must have enough electric currents to flow through on Q4 and R3.
The preamplifier constitutes input difference pair by Q1 and Q2, and used as current source load, R3 and R4 determines the electric current of Q3 and Q4 branch roads to Q3 and Q4, and Q8 and Q9 are biased as buffer stage by two current sources.Q13 and Q14 as Q10 and Q12 current source load.The effect of Q11 is the electric current of Q1 and Q2 branch roads is unlikely to excessive and cause R2 to control terminal voltage to have big difference with R1 terminal voltages, causes the asymmetric of Differential Input pipe.Efferent duct Q12 enables the circuitry to provide very low output impedance using the structure of emitter follower.
In the output amplifier, input difference to being made up of Q1 and Q2, Q3 and Q4 as Q1 and Q2 current source load, Q8 and Q9 is biased as current source as buffer stage, Q6 and Q7 to it.Q10 constitutes secondary voltage follower together with Q9, realizes DC level using PNP-NPN complementation pipes and moves.Input impedance can also be increased and forward gain is improved.Q11~Q13 provides bias current for efferent duct Q14.The structure of Q13 and Q14 composition Class A, to sacrifice power as cost, it is ensured that the signal for being amplified occurs without distortion as far as possible, and with the linearity and the larger amplitude of oscillation very high.In order that amplifier can steady operation, between the base stage of Q9 and the colelctor electrode of Q14 bridge R6 and C1, be used as frequency compensation.
The amplifier A1 applies negative-feedback in the base stage of Q8, and loop gain is sufficiently large, the differential input voltage of A1 is diminished, and obtains VA ≈ 2.5V.DAC1 controls the electric current of Q6 and Q7 branch roads, if the electric current I6 that Q6 is flowed through in DAC1 controls becomes big, A1 raises the base voltage C points current potential of Q8, so as to keep A point current potentials to be approximately 2.5V.The temperature coefficient of B point current potentials changes and changes with DAC1 output voltages.And the temperature coefficient and magnitude of voltage of A points be always maintained at it is constant.DAC2 controls the electric current I5 of Q5, and by amplifier A2 clamper Q3 collector potentials, the electric current of R1 branch roads is flowed through in control.If DAC2 output increases, R1 branch currents reduce, increase Q2 branch currents, because Vt is constant, cause Vc voltages to reduce.
The zero point offset temperature compensating coefficient electricity routing amplifier A1, transistor Q1, resistance R1 and resistance R3 compositions.When temperature is normal temperature, because Vo is accurately transferred on 2.5V this magnitude of voltage, it is known that the pressure drop on resistance R3 is 0.And when temperature change causes the value of Vo smaller than 2.5 V, the magnitude of voltage of Vol is raised, Q1 is opened, and Vol drives the NPN pipes work of DAC4, produces electric current Ie.Vo2 voltages now are directly pulled to supply voltage, and Q2 shut-offs, the PNP pipe in DCA4 does not work.The reference voltage of the DAC4 of this when is reference voltage Vol.
The beneficial effects of the invention are as follows：Structure is compact, and sample-adding high precision, speed are fast, and adaptability is good, instead of traditional pipettor, improves sample-adding efficiency, solves the problems, such as that Multi needle sample-adding syringe needle is wasted, and shortens chip detection analytical cycle.
Brief description of the drawings
The present invention is further described with reference to the accompanying drawings and examples.
Fig. 1 is compensation circuit overall structure figure of the invention.
Fig. 2 is band-gap reference source circuit figure of the invention.
Fig. 3 is the biasing circuit figure of amplifier of the invention.
Fig. 4 is pre-amplification circuit of the invention.
Fig. 5 is output amplifier of the invention.
Fig. 6 is full scale compensation of the invention and its tc compensation circuit.
Fig. 7 is zero point offset temperature compensating coefficient circuit of the invention.
Specific embodiment
The invention will be further described with reference to the accompanying drawings and examples.
Such as Fig. 1, the voltage Vin of Wheatstone bridge detection is amplified by OP1, the voltage of DAC1 and DAC2 acts on full scale and its tc compensation core circuit, exports an adjustable gain compensation electric current Ic to adjust the gain of OP1, finally produces an amplification electric current I1 with temperature-compensating；And the electric current I2 for compensation zero point imbalance that DAC3 is produced is added with I1 again after being added with an electric current I3 for compensating zero point output of the generation such as DAC4, DAC5 and zero temperature compensating coefficient core circuit, one is obtained by the electric current Io after temperature-compensating and offset compensation.By feedback resistance Rf, output voltage Vout of this compensation electric current after OP2 is converted to compensation.
Such as Fig. 2, band-gap reference source circuit is changed on the basis of Widlar band-gap references and formed.In mains fluctuations, the part of increased Q3, Q5 and Q6 causes output voltage stabilization by a feedback loop.
Such as Fig. 3, the effect of bias voltage circuit is to provide suitable bias voltage or electric current to modules such as each amplifier herein, digital analog converter and temperature-compensation circuits, and makes the stable working state of circuit.Rl, R2, Q1 and Q2 constitute Widlar current sources (micro-current source) circuit, and contacted a resistance R2 on Q2 emitter stages, if R2 ≠ 0, Ql and Q2 is operated under the different emitter voltages of base stage one.Q3, Q4, Q5, R3, R4 and R5 constitute a current source on the basis of VBE, in order that there is electric current to flow through in Q5, must have enough electric currents to flow through on Q4 and R3.
As Fig. 4, preamplifier constitute input difference pair by Q1 and Q2, used as current source load, R3 and R4 determines the electric current of Q3 and Q4 branch roads to Q3 and Q4, and Q8 and Q9 are biased as buffer stage by two current sources.Q13 and Q14 as Q10 and Q12 current source load.The effect of Q11 is the electric current of Q1 and Q2 branch roads is unlikely to excessive and cause R2 to control terminal voltage to have big difference with R1 terminal voltages, causes the asymmetric of Differential Input pipe.Efferent duct Q12 enables the circuitry to provide very low defeated using the structure of emitter follower
Go out impedance.
Such as Fig. 5, input difference to being made up of Q1 and Q2, Q3 and Q4 as Q1 and Q2 current source load, Q8 and Q9 is biased as current source as buffer stage, Q6 and Q7 to it.Q10 constitutes secondary voltage follower together with Q9, realizes DC level using PNP-NPN complementation pipes and moves.Input impedance can also be increased and forward gain is improved.Q11~Q13 provides bias current for efferent duct Q14.The structure of Q13 and Q14 composition Class A, to sacrifice power as cost, it is ensured that the signal for being amplified occurs without distortion as far as possible, and with the linearity and the larger amplitude of oscillation very high.In order that amplifier can steady operation, between the base stage of Q9 and the colelctor electrode of Q14 bridge R6 and C1, be used as frequency compensation.
As Fig. 6, amplifier A1 apply negative-feedback in the base stage of Q8, loop gain is sufficiently large, the differential input voltage of A1 is diminished, and obtains VA ≈ 2.5V.DAC1 controls the electric current of Q6 and Q7 branch roads, if the electric current I6 that Q6 is flowed through in DAC1 controls becomes big, A1 raises the base voltage C points current potential of Q8, so as to keep A point current potentials to be approximately 2.5V.The temperature coefficient of B point current potentials changes and changes with DAC1 output voltages.And the temperature coefficient and magnitude of voltage of A points be always maintained at it is constant.DAC2 controls the electric current I5 of Q5, and by amplifier A2 clamper Q3 collector potentials, the electric current of R1 branch roads is flowed through in control.If DAC2 output increases, R1 branch currents reduce, increase Q2 branch currents, because Vt is constant, cause Vc voltages to reduce.
Such as Fig. 7, it is made up of amplifier A1, transistor Q1, resistance R1 and resistance R3.When temperature is normal temperature, because Vo is accurately transferred on 2.5V this magnitude of voltage, it is known that the pressure drop on resistance R3 is 0.And when temperature change causes the value of Vo smaller than 2.5 V, the magnitude of voltage of Vol is raised, Q1 is opened, and Vol drives the NPN pipes work of DAC4, produces electric current Ie.Vo2 voltages now are directly pulled to supply voltage, and Q2 shut-offs, the PNP pipe in DCA4 does not work.The reference voltage of the DAC4 of this when is reference voltage Vol.
Claims (9)
1. a kind of compensation circuit of piezoresistive pressure sensor, it is characterized in that：The primary structure of described signal compensation circuit includes offset generating circuit, band-gap reference circuit, preamplifier OP1, output amplifier OP2, full range regulation and full scale tc compensation core circuit, DAC1, DAC2, zero temperature compensating coefficient core circuit.
2. the compensation circuit of a kind of piezoresistive pressure sensor according to claim 1, it is characterized in that：The band-gap reference source circuit is changed on the basis of Widlar band-gap references and formed, and in mains fluctuations, the part of increased Q3, Q5 and Q6 causes output voltage stabilization by a feedback loop.
3. the compensation circuit of a kind of piezoresistive pressure sensor according to claim 1, it is characterized in that：The effect of described bias voltage circuit is to provide suitable bias voltage or electric current to modules such as each amplifier herein, digital analog converter and temperature-compensation circuits, and makes the stable working state of circuit.
4. the compensation circuit of a kind of piezoresistive pressure sensor according to claim 1, it is characterized in that：Described preamplifier constitutes input difference pair by Q1 and Q2, and used as current source load, R3 and R4 determines the electric current of Q3 and Q4 branch roads to Q3 and Q4, and Q8 and Q9 are biased as buffer stage by two current sources.
5. the compensation circuit of a kind of piezoresistive pressure sensor according to claim 1, it is characterized in that：In the output amplifier, input difference to being made up of Q1 and Q2, Q3 and Q4 as Q1 and Q2 current source load, Q8 and Q9 is biased as current source as buffer stage, Q6 and Q7 to it.
6. the compensation circuit of a kind of piezoresistive pressure sensor according to claim 1, it is characterized in that：The amplifier A1 applies negative-feedback in the base stage of Q8, and loop gain is sufficiently large, the differential input voltage of A1 is diminished, and obtains VA ≈ 2.5V, and DAC1 controls the electric current of Q6 and Q7 branch roads.
7. the compensation circuit of a kind of piezoresistive pressure sensor according to claim 1, it is characterized in that：The zero point offset temperature compensating coefficient electricity routing amplifier A1, transistor Q1, resistance R1 and resistance R3 compositions.
8. the compensation circuit of a kind of piezoresistive pressure sensor according to claim 1, it is characterized in that：In the zero point offset temperature compensating coefficient circuit, DAC2 controls the electric current I5 of Q5, and by amplifier A2 clamper Q3 collector potentials, the electric current of R1 branch roads is flowed through in control.
9. the compensation circuit of a kind of piezoresistive pressure sensor according to claim 1, it is characterized in that：The zero point offset temperature compensating coefficient electricity routing amplifier A1, transistor Q1, resistance R1 and resistance R3 compositions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510913166.7A CN106873702A (en) | 2015-12-11 | 2015-12-11 | A kind of compensation circuit of piezoresistive pressure sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510913166.7A CN106873702A (en) | 2015-12-11 | 2015-12-11 | A kind of compensation circuit of piezoresistive pressure sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106873702A true CN106873702A (en) | 2017-06-20 |
Family
ID=59236871
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510913166.7A Pending CN106873702A (en) | 2015-12-11 | 2015-12-11 | A kind of compensation circuit of piezoresistive pressure sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106873702A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111694394A (en) * | 2019-03-15 | 2020-09-22 | 新唐科技股份有限公司 | Digital voltage stabilizing system and control method thereof |
| CN113359929A (en) * | 2021-07-23 | 2021-09-07 | 成都华微电子科技有限公司 | Band-gap reference circuit and low-offset high-power-supply-rejection-ratio band-gap reference source |
| CN115129102A (en) * | 2022-05-27 | 2022-09-30 | 深圳市泰德半导体有限公司 | Low dropout regulator circuit and power management chip |
-
2015
- 2015-12-11 CN CN201510913166.7A patent/CN106873702A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111694394A (en) * | 2019-03-15 | 2020-09-22 | 新唐科技股份有限公司 | Digital voltage stabilizing system and control method thereof |
| CN113359929A (en) * | 2021-07-23 | 2021-09-07 | 成都华微电子科技有限公司 | Band-gap reference circuit and low-offset high-power-supply-rejection-ratio band-gap reference source |
| CN115129102A (en) * | 2022-05-27 | 2022-09-30 | 深圳市泰德半导体有限公司 | Low dropout regulator circuit and power management chip |
| CN115129102B (en) * | 2022-05-27 | 2023-11-17 | 深圳市泰德半导体有限公司 | Low-dropout linear voltage regulator circuit and power management chip |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103488227B (en) | Band-gap reference voltage circuit | |
| CN108225588B (en) | Temperature sensor and temperature detection method | |
| CN106443134B (en) | Open-loop Hall current sensor and circuit | |
| CN107390761B (en) | A kind of CMOS integrated hall sensors temperature-compensation circuit | |
| CN109470376A (en) | CMOS temperature transmitter and temperature checking method | |
| CN109714054B (en) | Constant current source circuit and ternary discrete I/F analog-to-digital conversion circuit with same | |
| CN105487587A (en) | Calibration circuit of high-precision digital temperature sensor | |
| CN106873702A (en) | A kind of compensation circuit of piezoresistive pressure sensor | |
| CN102252700B (en) | Micro-cantilever beam piezoresistive bridge type sensor detecting instrument | |
| CN108106747A (en) | A kind of temperature sensor based on capacitive digital converter | |
| Ott | A new technique of thermal RMS measurement | |
| CN104764539A (en) | Universal and output-adjustable thermistor linear compensation circuit based on audion | |
| CN204964074U (en) | Single scale intergration pressure sensor signal modulate circuit | |
| CN102798466A (en) | APD (Avalanche Photo Diode) reverse bias voltage control circuit with temperature compensation | |
| RU2461048C1 (en) | Reference voltage source | |
| CN110737301B (en) | High-precision positive-negative adjustable type current stabilization system and method based on multi-operational amplifier feedback loop | |
| CN104713659A (en) | Thermistor resistance linear compensation circuit based on transistor output characteristic | |
| CN201247043Y (en) | Linear corrective circuit for electric vortex flow sensor | |
| CN109540313A (en) | A kind of linear temperature measurement circuit based on silicon-based diode and NTC thermistor | |
| JPS5849918B2 (en) | 2 Senshiki Henzo Fukuki | |
| CN108593128A (en) | A kind of high-precision temperature detection circuit with clamper function | |
| CN110440945B (en) | High-precision low-temperature drift discrete type double-matching constant current source temperature measuring circuit | |
| CN112504494B (en) | Ultra-low power consumption CMOS temperature sensing circuit | |
| CN211013290U (en) | High-precision low-temperature-drift discrete double-matching constant-current source temperature measurement circuit | |
| CN107515639A (en) | A kind of circuit for generating source voltage of Low Drift Temperature |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20170620 |
|
| WD01 | Invention patent application deemed withdrawn after publication |