CN109030571A - Micro-electrode amplifier - Google Patents
Micro-electrode amplifier Download PDFInfo
- Publication number
- CN109030571A CN109030571A CN201810628760.5A CN201810628760A CN109030571A CN 109030571 A CN109030571 A CN 109030571A CN 201810628760 A CN201810628760 A CN 201810628760A CN 109030571 A CN109030571 A CN 109030571A
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- Prior art keywords
- resistance
- capacitor
- output
- conditioning circuit
- signal conditioning
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/045—Circuits
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/12—Analogue/digital converters
- H03M1/124—Sampling or signal conditioning arrangements specially adapted for A/D converters
- H03M1/1245—Details of sampling arrangements or methods
Abstract
Micro-electrode amplifier, including microelectrode input circuit, sampling resistor, signal follower, the first signal conditioning circuit, second signal conditioning circuit, third signal conditioning circuit, fourth signal conditioning circuit, adder, the first D/A conversion unit, the second D/A conversion unit, third D/A conversion unit, AD conversion unit, processor, single knife switch, interface unit；The interface unit include for return to zero signal output return to zero output interface, for compensated signal output output interface, for pole resistance value output digital interface.The present invention is not only applicable to cell research, while can apply to environment measuring；Small in size, at low cost, performance stablizes the precision for being not only restricted to electronic device, can be realized pole resistance measurement, fly back, negative capacitance compensation.
Description
Technical field
The invention belongs to bio-instruments technical field more particularly to micro-electrode amplifiers.
Background technique
With the development of Life Sci-Tech, people to the research of the various types of cells tissue such as brain cell, cardiac muscle cell increasingly
Extensively, this just needs the microelectrode that can be inserted into biological cell to sample intracellular signal.
Microelectrode is the very thin electrode catheter of fingertip end.It can be used for measurement intracellular, can be used for extracellular measurement.It is right
In intracellular measurement, glass microelectrode is generallyd use, inside perfusion salting liquid (such as the KCL or NaCL of saturation) is clamped with electrode
Salt bridge is constituted between the metal contact of device, to constitute a part of circuit.Glass microelectrode tip is drawn with special instrument
It obtains very thin (diameter is usually no more than 1 μm), after needle point thin in this way is pierced into plant cell membrane, plasma membrane soon can be in needle point
It heals at piercing, to avoid cell membrane from being destroyed, and it is poor to be easy to get a more stable membrane potential.
Simplest glass microelectrode can be used to measure the potential difference inside and outside cell membrane.At this moment two electrodes are needed, one
It is measuring electrode (resistance of the measuring electrode is referred to as " pole resistance "), tip is tiny, and insertion is intracellular, the other is reference electrode,
Tip is slightly larger, is placed in extracellular.Two interelectrode potential differences are measured by electrometer, are remembered after amplifier amplifies by recorder
Record.
Due to its complexity functionally, the system structure of such product is complicated, complicated for operation, and performance is unstable
Fixed, the various and requirement high price to electronic device of production technology is high, and there are the larger mistakes due to electronic device and temperature drift to introduce
Measurement error.
Summary of the invention
It is an object of the present invention in view of the above-mentioned problems, propose a kind of micro-electrode amplifier.
Micro-electrode amplifier, including microelectrode input circuit, sampling resistor, signal follower, the first signal conditioning circuit,
Second signal conditioning circuit, third signal conditioning circuit, fourth signal conditioning circuit, adder, the first D/A conversion unit,
Two D/A conversion units, third D/A conversion unit, AD conversion unit, processor, single knife switch, interface unit；It is described to connect
Mouthful unit include for return to zero signal output return to zero output interface, for the output of compensated signal output interface, be used for
The digital interface of pole resistance value output.
The sampling resistor first end order double-pole double throw switch stationary contact；The sampling resistor second end, microelectrode input
Circuit output end follows circuit input end to be connected with signal；The signal follows circuit output end and the dynamic touching of single knife switch first
Point, adder first input end are connected.
The adder output connects micro-electrode amplifier and returns to zero output interface, second signal conditioning circuit input terminal；The
Binary signal conditioning circuit output end is connected by AD conversion unit with processor, and the quantization for returning to zero output signal acquires.
First output end of processor passes through the first D/A conversion unit and the first signal conditioning circuit input terminal；First
Signal conditioning circuit output end is connected with the second input terminal of adder.
The processor second output terminal is connected by the second AD conversion unit with third signal processing circuit input terminal,
Third signal conditioning circuit output end is connected with the second movable contact of single knife switch, for being superimposed with default pumping signal.
The processor third output end is connected by third D/A conversion unit with fourth signal conditioning circuit input terminal；
Fourth signal conditioning circuit output termination output interface unit.
Further, first signal conditioning circuit includes first resistor, second resistance, 3rd resistor, the first operation
Amplifier, first capacitor, the second capacitor, the first power supply；The first resistor first end and the first D/A converting circuit output end
It is connected；First resistor second terminates the first operational amplifier noninverting input, first capacitor first end；The first capacitor second
End ground connection；The second resistance first terminates the first D/A converting circuit reference voltage output terminal, the second resistance second end
Connect the first operational amplifier reverse input end, 3rd resistor first end, the second capacitor first end；The 3rd resistor second end,
Second capacitor second terminates the first operational amplifier output terminal, signal conditioning circuit output end.
Further, the second signal conditioning circuit include the 4th resistance, the 5th resistance, the 6th resistance, the 7th resistance,
Third capacitor, second operational amplifier；Second signal conditioning circuit reference voltage input terminal is by the 4th resistance respectively with second
Operational amplifier noninverting input, the 8th resistance first end, third capacitor first end are connected；The 8th resistance second end,
Three capacitor second ends ground connection；The adder output connects second operational amplifier reverse input end, the 7th by the 6th resistance
Resistance first end；7th resistance second terminates second operational amplifier output end, AD conversion unit input terminal.
Further, the third signal conditioning circuit includes the 8th resistance, the 9th resistance, the tenth resistance, third operation
Amplifier, the 4th capacitor, the 5th capacitor；The second D/A converting circuit output end connects the 8th resistance by the 8th resistance and connects
Four capacitor first ends, third operational amplifier noninverting input；The 4th capacitor second end ground connection；Third signal conditioning circuit
Reference voltage input terminal connects third operational amplifier reverse input end, the tenth resistance first end, the 5th capacitor by the 9th resistance
First end；The tenth resistance second end, the 5th capacitor second terminate third operational amplifier output terminal；The third operation is put
Big device output end order the second movable contact of knife-like switch is connected.
Further, the adder includes twelfth resistor, thirteenth resistor, the 14th resistance, the 15th resistance,
Six capacitors, the 7th capacitor, four-operational amplifier；The first signal conditioning circuit output end connects the tenth by twelfth resistor
Three resistance first ends, the 6th capacitor first end, four-operational amplifier noninverting input；The thirteenth resistor second end,
Six capacitor second ends ground connection；The signal follows circuit output end to connect four-operational amplifier by the 14th resistance and reversely inputs
End, the 15th resistance first end, the 7th capacitor first end；Four-operational amplifier output the 15th resistance second of termination
End, the 7th capacitor second end, adder output.
The beneficial effects of the present invention are: it is not only applicable to cell research, while being also applied to environment measuring；It is small in size；
It is at low cost；Performance stablizes the precision for being not only restricted to electronic device, can be realized pole resistance measurement, fly back, negative capacitance compensation.
Detailed description of the invention
Fig. 1 is the schematic diagram of micro-electrode amplifier；
Fig. 2 is the first signal conditioning circuit；
Fig. 3 is second signal conditioning circuit；
Fig. 4 is third signal conditioning circuit；
Fig. 5 is adder circuit.
Specific embodiment
To keep the purposes, technical schemes and advantages of inventive embodiments clearer, below in conjunction in the embodiment of the present invention
Attached drawing 1, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is this
Invention a part of the embodiment, instead of all the embodiments.The embodiment of the present invention described and illustrated in usual attached drawing 1 here
Component can arrange and design with a variety of different configurations.Based on the embodiments of the present invention, ordinary skill people
Member's every other embodiment obtained without creative efforts, shall fall within the protection scope of the present invention.
The present embodiment provides micro-electrode amplifiers, as shown in Figure 1, the system comprises microelectrode input circuits, sampling electricity
Resistance, signal follower, the first signal conditioning circuit, second signal conditioning circuit, third signal conditioning circuit, fourth signal conditioning
Circuit, adder, the first D/A conversion unit, the second D/A conversion unit, third D/A conversion unit, AD conversion unit,
MCU, single knife switch, interface unit；The interface unit include for return to zero signal output return to zero output interface, for compensating
The output interface of signal output afterwards, the digital interface exported for pole resistance value.
Sampling resistor first end order double-pole double throw switch stationary contact；The sampling resistor second end, microelectrode input circuit
Output end follows circuit input end to be connected with signal；The signal follows circuit output end and the first movable contact of single knife switch, adds
Musical instruments used in a Buddhist or Taoist mass first input end is connected.
Adder output connects micro-electrode amplifier and returns to zero output interface, second signal conditioning circuit input terminal；Second letter
Number conditioning circuit output end is connected by AD conversion unit with MCU, for returning to zero the quantization acquisition of output signal.
The first output end of MCU passes through the first D/A conversion unit and the first signal conditioning circuit input terminal；First signal tune
Reason circuit output end is connected with the second input terminal of adder.
MCU second output terminal is connected by the second AD conversion unit with third signal processing circuit input terminal, third letter
Number conditioning circuit output end is connected with the second movable contact of single knife switch, for being superimposed with default pumping signal.
MCU third output end is connected by third D/A conversion unit with fourth signal conditioning circuit input terminal；4th letter
Number conditioning circuit output termination output interface unit.
As shown in Fig. 2, the first signal conditioning circuit includes first resistor, second resistance, 3rd resistor, the first operation amplifier
Device, first capacitor, the second capacitor, the first power supply；The first resistor first end is connected with the first D/A converting circuit output end；
First resistor second terminates the first operational amplifier noninverting input, first capacitor first end；The first capacitor second terminates
Ground；The second resistance first terminates the first D/A converting circuit reference voltage output terminal, the termination of second resistance second the
One operational amplifier reverse input end, 3rd resistor first end, the second capacitor first end；The 3rd resistor second end, second
Capacitor second terminates the first operational amplifier output terminal, signal conditioning circuit output end.
As shown in figure 3, second signal conditioning circuit includes the 4th resistance, the 5th resistance, the 6th resistance, the 7th resistance, the
Three capacitors, second operational amplifier；Second signal conditioning circuit reference voltage input terminal is transported with second respectively by the 4th resistance
Amplifier noninverting input, the 8th resistance first end, third capacitor first end is calculated to be connected；The 8th resistance second end, third
Capacitor second end ground connection；The adder output connects second operational amplifier reverse input end, the 7th electricity by the 6th resistance
Hinder first end；7th resistance second terminates second operational amplifier output end, AD conversion unit input terminal.
As shown in figure 4, third signal conditioning circuit includes the 8th resistance, the 9th resistance, the tenth resistance, third operation amplifier
Device, the 4th capacitor, the 5th capacitor；The second D/A converting circuit output end connects the 8th resistance by the 8th resistance and connects the 4th electricity
Hold first end, third operational amplifier noninverting input；The 4th capacitor second end ground connection；The reference of third signal conditioning circuit
Voltage input end connects third operational amplifier reverse input end, the tenth resistance first end, the 5th capacitor first by the 9th resistance
End；The tenth resistance second end, the 5th capacitor second terminate third operational amplifier output terminal；The third operational amplifier
Output end order the second movable contact of knife-like switch is connected.
Fourth signal conditioning circuit uses and the first signal conditioning circuit same circuits.
As shown in figure 5, adder includes twelfth resistor, thirteenth resistor, the 14th resistance, the 15th resistance, the 6th
Capacitor, the 7th capacitor, four-operational amplifier；The first signal conditioning circuit output end connects the 13rd by twelfth resistor
Resistance first end, the 6th capacitor first end, four-operational amplifier noninverting input；The thirteenth resistor second end, the 6th
Capacitor second end ground connection；The signal follows circuit output end to connect four-operational amplifier by the 14th resistance and reversely inputs
End, the 15th resistance first end, the 7th capacitor first end；Four-operational amplifier output the 15th resistance second of termination
End, the 7th capacitor second end, adder output.
It is placed in the end a by making hilted broadsword pair set switch according to the control of connection interface control switch, carries out impedance by signal follower
Convert output signal V2；V2 generates V3 after synthesizing with V4 by adder and returns to zero signal.This signal is by second signal conditioning electricity
Road, which is sent, carries out quantization acquisition with analog-digital converter, according to the result of amount acquisition by the first number of fly back algorithm adjustment of MCU
Mode converter output valve is finally reached the average value of V3 level close to 0V level, realizes that fly back is adjusted.
It is placed in the end a by making hilted broadsword pair set switch according to the control of connection interface control switch, carries out impedance by signal follower
Convert output signal V2；V2 generates V3 after synthesizing with V4 by adder and returns to zero signal.This signal is by second signal conditioning electricity
Road, which is sent, to be given analog-digital converter and carries out quantization acquisition, according to the result of amount acquisition by the first number of fly back algorithm adjustment of MCU
Analog conversion circuit output valve is finally reached the average value of V3 level close to 0V level, hinders Measurement Algorithm by pole and realize pole resistance
It calculates, and external equipment is sent to by data-interface.
It is placed in the end a, is at this time normal acquisition mode by making hilted broadsword pair set switch according to the control of connection interface control switch, when
It needs to carry out to require when signal acquisition to keep in this state.After second signal conditioning circuit, signal becomes analog-to-digital conversion
Obtained signal can be passed through third by negative capacitance backoff algorithm in MCU collector with the signal of normal acquisition by device
D/A converting circuit, third signal conditioning circuit, output interface export the compensated final signal of negative capacitance, realize negative capacitance
Compensation.
In the description of the present invention, it should be noted that term " center ", "upper", "lower", "left", "right", "inner",
The orientation or positional relationship of the instructions such as "outside" be based on the orientation or positional relationship shown in the drawings or the utility model produce
Product using when the orientation or positional relationship usually put, be merely for convenience of description of the present invention and simplification of the description, rather than indicate
Or imply that signified device or element must have a particular orientation, be constructed and operated in a specific orientation, therefore cannot understand
For limitation of the present invention.In addition, term " first ", " second ", " third " etc. are only used for distinguishing description, and should not be understood as referring to
Show or imply relative importance.
Claims (5)
1. micro-electrode amplifier, which is characterized in that including microelectrode input circuit, sampling resistor, signal follower, the first signal
Conditioning circuit, second signal conditioning circuit, third signal conditioning circuit, fourth signal conditioning circuit, adder, the first digital-to-analogue turn
Change unit, the second D/A conversion unit, third D/A conversion unit, AD conversion unit, processor, single knife switch, interface list
Member；The interface unit includes the output for returning to zero output interface, exporting for compensated signal for returning to zero signal output
Interface, the digital interface exported for pole resistance value；
The sampling resistor first end order double-pole double throw switch stationary contact；The sampling resistor second end, microelectrode input circuit
Output end follows circuit input end to be connected with signal；The signal follows circuit output end and the first movable contact of single knife switch, adds
Musical instruments used in a Buddhist or Taoist mass first input end is connected；
The adder output connects micro-electrode amplifier and returns to zero output interface, second signal conditioning circuit input terminal；Second letter
Number conditioning circuit output end is connected by AD conversion unit with processor, for returning to zero the quantization acquisition of output signal；
First output end of processor passes through the first D/A conversion unit and the first signal conditioning circuit input terminal；First signal
Conditioning circuit output end is connected with the second input terminal of adder；
The processor second output terminal is connected by the second AD conversion unit with third signal processing circuit input terminal, third
Signal conditioning circuit output end is connected with the second movable contact of single knife switch, for being superimposed with default pumping signal；
The processor third output end is connected by third D/A conversion unit with fourth signal conditioning circuit input terminal；4th
Signal conditioning circuit output termination output interface unit.
2. micro-electrode amplifier according to claim 1, which is characterized in that first signal conditioning circuit includes the first electricity
Resistance, second resistance, 3rd resistor, the first operational amplifier, first capacitor, the second capacitor, the first power supply；The first resistor
One end is connected with the first D/A converting circuit output end；First resistor second terminates the first operational amplifier noninverting input, the
One capacitor first end；The first capacitor second end ground connection；The second resistance first terminates the reference of the first D/A converting circuit
Voltage output end, the second resistance second terminate the first operational amplifier reverse input end, 3rd resistor first end, the second electricity
Hold first end；The 3rd resistor second end, the second capacitor second terminate the first operational amplifier output terminal, signal conditioning circuit
Output end.
3. micro-electrode amplifier according to claim 1, which is characterized in that the second signal conditioning circuit includes the 4th electricity
Resistance, the 5th resistance, the 6th resistance, the 7th resistance, third capacitor, second operational amplifier；Second signal conditioning circuit is with reference to electricity
Press input terminal by the 4th resistance respectively with second operational amplifier noninverting input, the 8th resistance first end, third capacitor the
One end is connected；The 8th resistance second end, third capacitor second end ground connection；The adder output is connect by the 6th resistance
Second operational amplifier reverse input end, the 7th resistance first end；The 7th resistance second termination second operational amplifier is defeated
Outlet, AD conversion unit input terminal.
4. micro-electrode amplifier according to claim 1, which is characterized in that the third signal conditioning circuit includes the 8th electricity
Resistance, the 9th resistance, the tenth resistance, third operational amplifier, the 4th capacitor, the 5th capacitor；Second D/A converting circuit is defeated
Outlet connects the 8th resistance by the 8th resistance and connects the 4th capacitor first end, third operational amplifier noninverting input；Described 4th
Capacitor second end ground connection；It is reversed that third signal conditioning circuit reference voltage input terminal by the 9th resistance connects third operational amplifier
Input terminal, the tenth resistance first end, the 5th capacitor first end；The tenth resistance second end, the 5th capacitor second terminate third
Operational amplifier output terminal；The second movable contact of the third operational amplifier output terminal order knife-like switch is connected.
5. micro-electrode amplifier according to claim 1, which is characterized in that the adder includes eleventh resistor, the tenth
Two resistance, thirteenth resistor, the 14th resistance, the 15th resistance, the 6th capacitor, the 7th capacitor, four-operational amplifier；It is described
First signal conditioning circuit output end connects thirteenth resistor first end, the 6th capacitor first end, the 4th fortune by twelfth resistor
Calculate amplifier noninverting input；The thirteenth resistor second end, the 6th capacitor second end ground connection；The signal follows circuit defeated
Outlet connects four-operational amplifier reverse input end, the 15th resistance first end, the 7th capacitor first end by the 14th resistance；
Four-operational amplifier output termination the 15th resistance second end, the 7th capacitor second end, adder output.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810628760.5A CN109030571A (en) | 2018-06-19 | 2018-06-19 | Micro-electrode amplifier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810628760.5A CN109030571A (en) | 2018-06-19 | 2018-06-19 | Micro-electrode amplifier |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109030571A true CN109030571A (en) | 2018-12-18 |
Family
ID=64609910
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|---|---|---|---|
| CN201810628760.5A Pending CN109030571A (en) | 2018-06-19 | 2018-06-19 | Micro-electrode amplifier |
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| GB2281160A (en) * | 1993-08-17 | 1995-02-22 | Peter Fred Blomley | Compensation for temperature drift and input offset in differential amplifiers |
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| CN202043080U (en) * | 2011-03-28 | 2011-11-16 | 武汉大学 | Broadband direct current amplification device |
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| CN107941417A (en) * | 2017-11-10 | 2018-04-20 | 苏州华兴源创电子科技有限公司 | The output calibrating installation and method of a kind of pressure sensor |
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| US4193039A (en) * | 1978-02-10 | 1980-03-11 | The Valeron Corporation | Automatic zeroing system |
| GB2281160A (en) * | 1993-08-17 | 1995-02-22 | Peter Fred Blomley | Compensation for temperature drift and input offset in differential amplifiers |
| KR20040042651A (en) * | 2002-11-15 | 2004-05-20 | 엘지전자 주식회사 | Apparatus for Compensating for nonlinear of Power Amplifier |
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