CN107315439A - High-precision voltage controlled current source circuit - Google Patents
High-precision voltage controlled current source circuit Download PDFInfo
- Publication number
- CN107315439A CN107315439A CN201710676051.XA CN201710676051A CN107315439A CN 107315439 A CN107315439 A CN 107315439A CN 201710676051 A CN201710676051 A CN 201710676051A CN 107315439 A CN107315439 A CN 107315439A
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- China
- Prior art keywords
- resistance
- operational amplifier
- current source
- pmosfet
- reference voltage
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- 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.)
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Classifications
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- 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
- G05F1/561—Voltage to current converters
Abstract
The present invention relates to a kind of high-precision voltage controlled current source circuit, including reference voltage V i, operational amplifier U1, PMOSFET pipe Q1, range resistance Rs, resistance R1 and resistance R2；Reference voltage V 1 is connected to operational amplifier U1 inverting input by range resistance Rs, reference voltage is connected to operational amplifier U1 in-phase input ends by resistance R1, resistance R1 other end connection resistance R2 one end, resistance R2 other end ground connection, operational amplifier U1 output end is connected to the grid of PMOSFET pipes, the source electrode of PMOSFET pipes is connected to operational amplifier U1 inverting input to constitute negative feedback paths, the drain electrodes of PMOSFET pipes as constant-current source current output terminal.Output energy of the present invention due to being provided current source using input reference voltage, had both been simplified circuit design and has saved cost, is reduced the overall complexity of circuit, this circuit is less subject to the interference of power-supply fluctuation, improve the accuracy and stability of electric current.
Description
Technical field
The present invention relates to instrument and meter and electronic surveying field, especially a kind of high-precision voltage controlled current circuit can be applied
In direct current resistance m easurem ent.
Background technology
High-precision voltage-controlled current source is the instrument and equipment commonly used in electronic surveying and measurement and calibration, in industrial and mining enterprises and experiment
Extensive use in room.
Traditional high-precision voltage controlled current source circuit as shown in Figure 1, reference voltage V i, operational amplifier U1, NMOSFET
Power tube Q1 power supplys VCC, resistance R1, resistance R2 and resistance R4 constitute the first current source；First current source flows through resistance R2, Yu
Resistance R2 two ends produce fixed voltage difference, and according to operational amplifier " empty short " and " void is disconnected " concept, computing is flowed into without electric current
Amplifier U2 input, then the voltage difference at range resistance Rs two ends is equal with the voltage difference at resistance R2 two ends, then in range
Fixed voltage difference is formed on resistance, fixed electric current, operational amplifier U2 connection PMOSFET power tubes Q2 is further then produced
Grid, Q2 source electrode is connected to operational amplifier U2 inverting input to constitute negative-feedback to keep the constant of electric current.
This traditional voltage controlled current source circuit, output current energy comes from power supply, easily disturbed by power supply noise；Circuit knot
Structure is complicated, and electronic component quantity is more；Area is big needed for making PCB, and cost is high.
The content of the invention
The technical problem to be solved in the present invention is：A kind of high-precision voltage controlled current source circuit is proposed, using reference voltage source
Originated as output current energy, relative to traditional high-precision voltage controlled current source circuit, its simple in construction, electronic component
Quantity is few, and shared pcb board area is small, and cost is low；Parameter can be adjusted flexibly according to use condition, various varying strength electricity are exported
Stream；Circuit entirety complexity is low, it is easy to promotes, has a good application prospect.
The technical solution adopted in the present invention is：A kind of high-precision voltage controlled current source circuit, including reference voltage V i, computing
Amplifier U1, PMOSFET pipe Q1, range resistance Rs, resistance R1 and resistance R2；Reference voltage V 1 is connected to by range resistance Rs
Operational amplifier U1 inverting input, reference voltage is connected to operational amplifier U1 in-phase input ends, resistance by resistance R1
R1 other end connection resistance R2 one end, resistance R2 other end ground connection, operational amplifier U1 output end is connected to
The grid of PMOSFET pipes, the source electrode of PMOSFET pipes is connected to operational amplifier U1 inverting input to constitute negative-feedback road
Footpath, the drain electrodes of PMOSFET pipes as constant-current source current output terminal.
Further, reference voltage V i of the present invention is connected to range resistance Rs one end and resistance R1 one end, range
Resistance Rs other end concatenation operation amplifier U1 inverting input and the source electrode of PMOSFET pipes, the resistance R1 other end connects
It is connected to operational amplifier U1 in-phase input end and resistance R2 one end, resistance R2 other end ground connection；
Further say, operational amplifier U1 of the present invention output end is connected to the grid of PMOSFET pipes, PMOSFET
The source electrode of pipe is connected to operational amplifier U1 inverting input, the drain electrodes of PMOSFET pipes as constant-current source current output terminal,
The load of constant-current source is by the way of grounding connection.
Further say, the present invention is using sources of the reference voltage V i as the energy of output current, resistance R1 and electricity
Resistance R2 plays partial pressure effect to reference voltage V i so that operational amplifier U1 homophase input terminal voltage is less than reference voltage V i.
Further say, it is of the invention by carry out expansion stream of the PMOSFET pipes to operational amplifier U1, meanwhile, by computing
Amplifier U1 reversed-phase output is connected with the source electrode by PMOSFET pipes so that operational amplifier formation closure negative-feedback, is led to
Operational amplifier control electric current accuracy is crossed, realizes voltage to the conversion of electric current, current source by the transfer characteristic of PMOSFET pipes
Precision high-performance is stable.
Further say, the present invention can be improved by changing reference voltage V i magnitude of voltage and output current ability
The exportable current strength of the present invention.
Further say, the present invention can realize that current value is big by changing range resistance Rs, resistance R1 and resistance R2
Small regulation, with the requirement for the accurate measurement for adapting to different Standard resistance range resistance.
Further say, the present invention can be according to use condition, adjusting parameter, it is adaptable to which different current strength outputs will
Ask.
The beneficial effects of the invention are as follows：Due to providing the output energy of current source using input reference voltage, both simplified
Circuit design saves cost, reduces the overall complexity of circuit, this circuit is less subject to the interference of power-supply fluctuation,
Improve the accuracy and stability of electric current.
Brief description of the drawings
The present invention is further described with reference to the accompanying drawings and examples.
Fig. 1 is traditional high-precision voltage-controlled current source circuit theory diagrams；
Fig. 2 is the circuit theory diagrams of the present invention；
Fig. 3 is a kind of voltage-controlled current source circuit diagram in present invention specific implementation.
Embodiment
Presently in connection with accompanying drawing and preferred embodiment, the present invention is further detailed explanation.These accompanying drawings are simplified
Schematic diagram, only illustrates the basic structure of the present invention in a schematic way, therefore it only shows the composition relevant with the present invention.
A kind of voltage-controlled current source circuit theory diagrams as shown in Figure 2, the general principle to the present invention is shifted onto：If input
Reference voltage be Vi, operational amplifier U1 in-phase input end potential be Vp, operational amplifier U1 inverting input potentials be Vn,
Output current is that the source current of Iout, PMOSFET pipe is Is, then,
Because " void is disconnected " feature of operational amplifier, the electric current for flowing through operational amplifier U1 in-phase input ends is zero, then flows
The electric current for crossing resistance R1 and resistance R2 is equal, so
By " empty short " feature of operational amplifier, have：
Vn=Vp (2)
Because " void is disconnected ", also no electric current flows through operational amplifier U1 inverting inputs, so flowing through range resistance Rs's
Electric current is equal with flowing through PMOSFET pipe source currents, so
According to PMOSFET FET manufacturing technical features, its transfer characteristic id=f (Vgs), flow through PMOSFET pipe Q1 sources
The electric current of pole is equal with drain current, so
Iout=Is (4)
So, according to (1), (2), (3) and (4) formula, it can obtain
IfThen (5) can be reduced to
Iout=kVi (6)
From formula (6)：Circuit output current i.e. shown in Fig. 2 is directly proportional to input voltage, so this circuit is exactly one
Plant voltage-controlled current source.
Due to providing the output energy of current source using input reference voltage, both simplified circuit design and saved cost,
The overall complexity of circuit is reduced, this circuit is less subject to the interference of power-supply fluctuation, improves the accuracy of electric current
And stability.
Circuit diagram as shown in figure 3,
R20, R21, R22, RL are resistance；
R20, R21 serve as divider resistance, and R22 is range resistance；
RL is load；
C10, C11, CA101, CA102 are electric capacity；
Power supply on the basis of UA101；
U2 is operational amplifier；
Q4 is PMOSFET power tubes；
+ 15V is positive 15V supply voltages, and -15V is negative 15V supply voltages；
The 5V reference voltages that voltage source is produced on the basis of VREF5V；
The framework of whole circuit is 5V reference voltages by resistance R20 and resistance R21 partial pressures, in operational amplifier with mutually defeated
Enter to hold generation+3V voltages, then in range resistance R22 two ends formation+2V voltage difference, further resistance R22 is produced on range
Raw 1mA electric current, this electric current passes through from power tube Q1 source electrode to drain electrode, eventually as the defeated of voltage controlled current source circuit generation
Go out current load to load RL.
The embodiment of the simply present invention described in description above, the reality of various illustrations not to the present invention
Matter Composition of contents is limited, and person of an ordinary skill in the technical field can be to described in the past specific after specification has been read
Embodiment is made an amendment or deformed, without departing from the spirit and scope of the invention.
Claims (5)
1. a kind of high-precision voltage controlled current source circuit, it is characterised in that：Including reference voltage V i, operational amplifier U1, PMOSFET
Pipe Q1, range resistance Rs, resistance R1 and resistance R2；Reference voltage V 1 is connected to the anti-of operational amplifier U1 by range resistance Rs
Phase input, reference voltage is connected to operational amplifier U1 in-phase input ends, resistance R1 other end connection electricity by resistance R1
R2 one end is hindered, resistance R2 other end ground connection, operational amplifier U1 output end is connected to the grid of PMOSFET pipes,
The source electrode of PMOSFET pipes is connected to operational amplifier U1 inverting input to constitute negative feedback paths, the leakage of PMOSFET pipes
Pole as constant-current source current output terminal.
2. high accuracy voltage controlled current source circuit as claimed in claim 1, it is characterised in that：Described reference voltage V i is connected to
Range resistance Rs one end and resistance R1 one end, range resistance Rs other end concatenation operation amplifier U1 inverting input
With the source electrode of PMOSFET pipes, the resistance R1 other end is connected to operational amplifier U1 in-phase input end and resistance R2 one end,
Resistance R2 other end ground connection.
3. high accuracy voltage controlled current source circuit as claimed in claim 1, it is characterised in that：Described operational amplifier U1's is defeated
Go out the grid that end is connected to PMOSFET pipes, the source electrode of PMOSFET pipes is connected to operational amplifier U1 inverting input,
The drain electrode of PMOSFET pipes is as the current output terminal of constant-current source, and the load of constant-current source is by the way of grounding connection.
4. high accuracy voltage controlled current source circuit as claimed in claim 2, it is characterised in that：Reference voltage V i is used as output current
Energy source, resistance R1 and resistance R2 play partial pressure effect to reference voltage V i so that operational amplifier U1's is same mutually defeated
Enter terminal voltage less than reference voltage V i.
5. high accuracy voltage controlled current source circuit as claimed in claim 3, it is characterised in that：PMOSFET pipes are to operational amplifier
U1 carry out expansion stream, meanwhile, operational amplifier U1 reversed-phase output is connected with the source electrode by PMOSFET pipes so that computing
Amplifier formation closure negative-feedback, by operational amplifier control electric current accuracy, is realized by the transfer characteristic of PMOSFET pipes
Voltage is to the conversion of electric current, and current source precision high-performance is stably.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710676051.XA CN107315439A (en) | 2017-08-09 | 2017-08-09 | High-precision voltage controlled current source circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710676051.XA CN107315439A (en) | 2017-08-09 | 2017-08-09 | High-precision voltage controlled current source circuit |
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| CN107315439A true CN107315439A (en) | 2017-11-03 |
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| CN201710676051.XA Pending CN107315439A (en) | 2017-08-09 | 2017-08-09 | High-precision voltage controlled current source circuit |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109901649A (en) * | 2017-12-08 | 2019-06-18 | 上海力声特医学科技有限公司 | Current-limiting circuit, cochlear implantation prosthesis and cochlear implant |
| CN110687951A (en) * | 2019-10-15 | 2020-01-14 | 博能传动(苏州)有限公司 | High-precision voltage-controlled current source capable of being quickly turned off |
| CN113485507A (en) * | 2021-07-07 | 2021-10-08 | 深圳东昇射频技术有限公司 | High-precision anti-noise multiplication control voltage-to-current method |
| CN113498227A (en) * | 2021-07-09 | 2021-10-12 | 西安和其光电科技股份有限公司 | Adjustable microampere constant current source circuit, excitation light source and control method thereof |
| CN113531491A (en) * | 2021-07-09 | 2021-10-22 | 西安和其光电科技股份有限公司 | Ultraviolet light emitting diode installation, curing and monitoring integrated system and installation and curing method |
| CN114063494A (en) * | 2021-10-29 | 2022-02-18 | 重庆前卫表业有限公司 | Temperature sensor drive circuit and gas table of gas volume correction appearance |
| WO2022245233A1 (en) * | 2021-05-17 | 2022-11-24 | Закрытое Акционерное Общество "Драйв" | Controller for an electronically controlled resistor |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1063945A (en) * | 1990-02-10 | 1992-08-26 | 德国汤姆森-勃朗特有限公司 | Frequency compensated circuit |
| US5978240A (en) * | 1997-10-07 | 1999-11-02 | Stmicroelectronics S.R.L. | Fully differential voltage-current converter |
| US20080290934A1 (en) * | 2008-06-24 | 2008-11-27 | Mediatek Inc. | Reference buffer circuits |
| CN205176715U (en) * | 2015-10-22 | 2016-04-20 | 国家电网公司 | Adopt CT to replace voltage control current source circuit of electric current sensing resistance |
| CN205608577U (en) * | 2016-05-06 | 2016-09-28 | 科大国盾量子技术股份有限公司 | Voltage -controlled current source circuit , semiconductor laser and bias supply thereof |
-
2017
- 2017-08-09 CN CN201710676051.XA patent/CN107315439A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1063945A (en) * | 1990-02-10 | 1992-08-26 | 德国汤姆森-勃朗特有限公司 | Frequency compensated circuit |
| US5978240A (en) * | 1997-10-07 | 1999-11-02 | Stmicroelectronics S.R.L. | Fully differential voltage-current converter |
| US20080290934A1 (en) * | 2008-06-24 | 2008-11-27 | Mediatek Inc. | Reference buffer circuits |
| CN205176715U (en) * | 2015-10-22 | 2016-04-20 | 国家电网公司 | Adopt CT to replace voltage control current source circuit of electric current sensing resistance |
| CN205608577U (en) * | 2016-05-06 | 2016-09-28 | 科大国盾量子技术股份有限公司 | Voltage -controlled current source circuit , semiconductor laser and bias supply thereof |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109901649A (en) * | 2017-12-08 | 2019-06-18 | 上海力声特医学科技有限公司 | Current-limiting circuit, cochlear implantation prosthesis and cochlear implant |
| CN109901649B (en) * | 2017-12-08 | 2024-03-26 | 上海力声特医学科技有限公司 | Current limiting circuit, cochlear implant and electronic cochlea |
| CN110687951A (en) * | 2019-10-15 | 2020-01-14 | 博能传动(苏州)有限公司 | High-precision voltage-controlled current source capable of being quickly turned off |
| WO2022245233A1 (en) * | 2021-05-17 | 2022-11-24 | Закрытое Акционерное Общество "Драйв" | Controller for an electronically controlled resistor |
| CN113485507A (en) * | 2021-07-07 | 2021-10-08 | 深圳东昇射频技术有限公司 | High-precision anti-noise multiplication control voltage-to-current method |
| CN113498227A (en) * | 2021-07-09 | 2021-10-12 | 西安和其光电科技股份有限公司 | Adjustable microampere constant current source circuit, excitation light source and control method thereof |
| CN113531491A (en) * | 2021-07-09 | 2021-10-22 | 西安和其光电科技股份有限公司 | Ultraviolet light emitting diode installation, curing and monitoring integrated system and installation and curing method |
| CN113531491B (en) * | 2021-07-09 | 2022-08-19 | 西安和其光电科技股份有限公司 | Ultraviolet light emitting diode installation, solidification and monitoring integrated system and installation and solidification method |
| CN114063494A (en) * | 2021-10-29 | 2022-02-18 | 重庆前卫表业有限公司 | Temperature sensor drive circuit and gas table of gas volume correction appearance |
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Application publication date: 20171103 |
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