CN203838587U - Numerical-control direct current source - Google Patents
Numerical-control direct current source Download PDFInfo
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- CN203838587U CN203838587U CN201420083783.XU CN201420083783U CN203838587U CN 203838587 U CN203838587 U CN 203838587U CN 201420083783 U CN201420083783 U CN 201420083783U CN 203838587 U CN203838587 U CN 203838587U
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Abstract
The utility model discloses a numerical-control direct current source. The numerical-control direct current source comprises a controller, a keyboard, a displayer, an analog-to-digital conversion circuit, a digital-to-analog conversion circuit, a constant current source circuit comprising a sampling resistor, and a current output interface. The controller is electrically connected with the keyboard, the displayer, the analog-to-digital conversion circuit and the digital-to-analog conversion circuit. The output end of the analog-to-digital conversion circuit and the input end of the digital-to-analog conversion circuit are electrically connected with the constant current source circuit respectively. The constant current source circuit is electrically connected with the current output interface. The numerical-control direct current source has the advantages of being high in output current accuracy and stability, wide in output current regulation range, capable of carrying out real-time monitoring and timely adjustment on supply current.
Description
Technical field
The utility model relates to power-supply device technical field, especially relates to a kind of output current precision and degree of stability high, and output current range of adjustment is wide, the Digital Control Direct Current Source that can monitor in real time and carry out adjusting in time supply current.
Background technology
DC current source is a kind of power supply that can export steady current, and DC current source tool has the following advantages:
For example, when utilizing charger to charge a battery, along with the rising of battery tension, charging current reduces accordingly, in order to guarantee normal charging, must improve at any time the output voltage of charger; When adopting constant current source to charge a battery, the charging current in charging process needn't be adjusted;
DC current source is widely used in as sensor power supplies such as temperature-sensitive, pressure-sensitive, photosensitive, magnetosensitive, wet sensitives, can effectively avoid the conductor resistance of connecting sensor and the impact that contact resistance causes the precision of sensor.
But common DC current source exists output current adjustable extent little, the problem that the stability of output current and precision are poor.
Chinese patent mandate publication number: CN202818114U, authorize open day on October 16th, 2012, a kind of LED lamp constant-current supply is disclosed, comprise: a rectification circuit is connected in the Same Name of Ends of the first primary coil of a transformer, the different name end of the first primary coil is connected in one end of the first resistance and the collector of the first transistor, the other end of the first resistance is connected in one end of the second electric capacity, the base stage of the first transistor and the collector of transistor seconds, the other end of the second electric capacity is connected in one end of the 4th resistance, the other end of the 4th resistance is connected in the Same Name of Ends of the second primary coil, the emitter of the first transistor is connected in the second resistance, one end of the 5th resistance, the other end of the 5th resistance is connected in the base stage of transistor seconds, the different name end of the second primary coil, the other end of the second resistance, the emitter of transistor seconds is connected in rectification circuit, secondary coil two ends are connected to one end of the 3rd electric capacity, the anode of the second diode, and the other end of the 3rd electric capacity is connected in the negative electrode of the second diode.The weak point of this utility model is that function singleness, can not be for giving other electric equipment power supply.
Summary of the invention
Goal of the invention of the present utility model is little in order to overcome the output current adjustable extent of DC current source of the prior art, the deficiency that the stability of output current and precision are poor, provide a kind of output current precision and degree of stability high, output current range of adjustment is wide, the Digital Control Direct Current Source that can monitor in real time and carry out adjusting in time supply current.
To achieve these goals, the utility model is by the following technical solutions:
A Digital Control Direct Current Source, comprises controller, keyboard, display, analog to digital conversion circuit, D/A converting circuit, the constant-current source circuit that comprises sampling resistor and electric current output interface; Described controller is electrically connected to keyboard, display, analog to digital conversion circuit and D/A converting circuit respectively, the output terminal of analog-digital conversion circuit as described and the input end of D/A converting circuit are electrically connected to constant-current source circuit respectively, and described constant-current source circuit is electrically connected to electric current output interface.Electric current output interface place is connected with load.
The D/A converting circuit that Digital Control Direct Current Source of the present utility model adopts controller to control provides reference voltage, has improved precision of the present utility model and serviceable life.
The utility model is by the preset output current value of keyboard, and controller is exported corresponding digital signal to D/A converting circuit, and D/A converting circuit outputting analog signal, to constant-current source circuit, is controlled the size of current of output.Electric current in load is sampled and is become voltage signal by sampling resistor again, and analog to digital conversion circuit is by signal feedback in controller, and controller, by feedback signal and prevalue comparison, is adjusted the size of output current signal according to difference between the two; Feedback regulation of the present utility model, has improved stability and the precision of output current, and the current value of output shows by display screen.
Therefore, the utlity model has output current precision and degree of stability high; Output current range of adjustment is wide; The feature that can monitor in real time and carry out adjusting in time supply current.
As preferably, described constant-current source circuit comprises LM358AN amplifier, OP07Z amplifier, and resistance R 1, R2, R3, R4, R5 and triode Q1, Q2, described sampling resistor is RS; The in-phase input end of OP07Z amplifier is electrically connected to the input end of analog to digital conversion circuit by resistance R 1, the inverting input of OP07Z amplifier is electrically connected to the output terminal of LM358AN amplifier and one end of resistance R 4 respectively, the output terminal of OP07Z amplifier is electrically connected to the base stage of triode Q1, the emitter of Q1 is electrically connected to the base stage of triode Q2, and the collector of triode Q1 and triode Q2 is all electrically connected to electric current output interface; The R4 other end is electrically connected to inverting input and R5 one end of LM358AN amplifier respectively, the in-phase input end of LM358AN amplifier is electrically connected to one end of resistance R 2 and resistance R 3 respectively, resistance R 2 other end ground connection, resistance R 3 other ends are electrically connected to emitter and resistance R S one end of triode Q2 respectively, and the resistance R S other end and resistance R 5 other ends are electrically connected to and ground connection.
The scheme that the utility model adopts LM358AN amplifier, OP07Z amplifier and triode Q1, Q2 to combine, D/A converting circuit output voltage is as the reference voltage of constant current source, the compound Darlington circuit that operational amplifier OP07 and transistor Q1, Q2 form forms voltage follower, utilizes the output characteristics that transistor is smooth can obtain constant current output.Thereby make the utility model current source there is better stability.
As preferably, also comprise crystal oscillating circuit and reset circuit, described crystal oscillating circuit and reset circuit are electrically connected to controller respectively.
Controller must could be worked under the driving of crystal oscillating circuit, in controller inside, there is a clock oscillation circuit, crystal oscillating circuit provides oscillation source to clock oscillation circuit, thereby make clock oscillation circuit produce certain clock signal and deliver to the unit of controller inside, and determining the operating rate of controller.
Reset circuit, for when controller is made mistakes, carries out reset operation.
As preferably, described D/A converting circuit comprises LTC2622 digital to analog converter, triode Q4, amplifier U2A, slide rheostat RP1 and resistance R 7; The the 1st, the 2nd and the 3rd pin of described LTC2622 digital to analog converter is all electrically connected to controller, the 4th pin is connected with power supply VCC by resistance R 7, the 4th pin is electrically connected to the emitter of triode Q4, triode Q4 grounded collector, the 5th pin is electrically connected to the in-phase input end of slide rheostat RP1 one end and amplifier U2A respectively, the equal ground connection of the other end of slide rheostat RP1 and centre tap, the inverting input of amplifier U2A and output terminal are all electrically connected to the input end of constant-current source circuit.
As preferably, analog-digital conversion circuit as described comprises TLC2552 analog to digital converter, resistance R 6 and triode Q3; The the 1st, the 7th and the 8th pin of TLC2552 analog to digital converter is all electrically connected to controller, the the 4th and the 5th pin is all electrically connected to the output terminal of constant-current source circuit, the 2nd pin is electrically connected to one end of resistance R 6 and the emitter of triode Q3 respectively, the grounded collector of triode Q3, another termination power of R6 VCC.
The model of triode Q1, Q2, Q3 and Q4 is 2N3904.
As preferably, keyboard is 4 * 4 keyboards, comprises 0 to 9 digital input key, increases and builds, reduces and build, arrange key, acknowledgement key, # keyboard and cancel key.4 * 4 keyboards adopt the mode of matrix form rank scannings, and have and when button is more, can reduce the I/O mouth number that takies single-chip microcomputer, and directly input current value and feature that needn't stepping.
As preferably, it is ultra-thin light and handy that display is that LCD1602 liquid crystal display LCD1602 liquid crystal display has, and displaying contents is abundant, and resolution is high, and antijamming capability is strong, and power consumption is little, the advantage of simplicity of design.
As preferably, controller is AT89S52 single-chip microcomputer.
It is simple that AT89S52 single-chip microcomputer has system, easily make PCB, arithmetic function is powerful, software programming is flexible, can be by ISP mode, program is quick-downloading to chip, be convenient to the renewal of the program that realizes, degree of freedom is large, brought into play preferably the dirigibility of C language, available programming realizes various algorithms and logic control, also have simultaneously low in energy consumption, volume is little, technology maturation and low cost and other advantages.
AT89C52 single-chip microcomputer is changed by being converted current marching technique value or setting value by D/A converting circuit, drive constant-current source circuit to realize electric current output.Output current feeds back to Single Chip Microcomputer (SCM) system through analog to digital conversion circuit conversion, adjusts the output of electric current by backoff algorithm, with this, improves the precision and stability of output.
As preferably, sampling resistor is health copper-manganese resistance wire.
It is little that health copper-manganese resistance wire has temperature drift amount, and temperature coefficient is about 5ppm/ ℃.Through test, on the health copper-manganese resistance wire of 1 Ω, by 2A electric current, the intensification because the heat producing causes, only can cause the change in resistance of 0.02 Ω left and right, electric current stable has been play a part very important.In addition, the health copper-manganese resistance wire of 1 Ω is about 1m, due to large with extraneous contact area, even if logical super-high-current also can dispel the heat very soon, has further reduced the impact that temperature drift brings.
Therefore, the utlity model has following beneficial effect: (1) output current precision and degree of stability are high; (2) output current range of adjustment is wide; (3) can supply current be monitored in real time and be adjusted in time; (4) long service life.
Accompanying drawing explanation
Fig. 1 is a kind of theory diagram of the present utility model;
Fig. 2 is a kind of circuit diagram of the present utility model;
Fig. 3 is a kind of circuit diagram of constant-current source circuit of the present utility model;
Fig. 4 is a kind of circuit diagram of D/A converting circuit of the present utility model;
Fig. 5 is a kind of circuit diagram of analog to digital conversion circuit of the present utility model.
In figure: controller 1, keyboard 2, display 3, analog to digital conversion circuit 4, D/A converting circuit 5, constant-current source circuit 6, electric current output interface 7, crystal oscillating circuit 8, reset circuit 9.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is further described.
Embodiment is as shown in Figure 1 a kind of Digital Control Direct Current Source, comprises controller 1, keyboard 2, display 3, analog to digital conversion circuit 4, D/A converting circuit 5, the constant-current source circuit 6 that comprises sampling resistor and electric current output interface 7; Controller is electrically connected to keyboard, display, analog to digital conversion circuit and D/A converting circuit respectively, and the output terminal of analog to digital conversion circuit and the input end of D/A converting circuit are electrically connected to constant-current source circuit respectively, and constant-current source circuit is electrically connected to electric current output interface.
As shown in Figure 3, constant-current source circuit comprises LM358AN amplifier, OP07Z amplifier, and resistance R 1, R2, R3, R4, R5 and triode Q1, Q2, described sampling resistor is RS; The in-phase input end of OP07Z amplifier is electrically connected to the input end of analog to digital conversion circuit by resistance R 1, the inverting input of OP07Z amplifier is electrically connected to the output terminal of LM358AN amplifier and one end of resistance R 4 respectively, the output terminal of OP07Z amplifier is electrically connected to the base stage of triode Q1, the emitter of Q1 is electrically connected to the base stage of triode Q2, and the collector of triode Q1 and triode Q2 is all electrically connected to electric current output interface; The R4 other end is electrically connected to inverting input and R5 one end of LM358AN amplifier respectively, the in-phase input end of LM358AN amplifier is electrically connected to one end of resistance R 2 and resistance R 3 respectively, resistance R 2 other end ground connection, resistance R 3 other ends are electrically connected to emitter and resistance R S one end of triode Q2 respectively, and the resistance R S other end and resistance R 5 other ends are electrically connected to and ground connection.
OP07 has lower input offset voltage, does not need the low and high feature of open-loop gain of extra zeroing measure and input bias current.
As shown in Figure 1 and Figure 2, also comprise crystal oscillating circuit 8 and reset circuit 9, crystal oscillating circuit and reset circuit are electrically connected to controller respectively.
The frequency of the quartz oscillator in crystal oscillating circuit is 11.0592MHz, and the effect of two capacitor C 1, C2 is help oscillator starting of oscillation and the frequency of oscillator is finely tuned, and C1, C2 are 33PF.
The reset signal of reset circuit is sent into single-chip microcomputer by RST pin, resets.As long as RST end keeps high level more than 10ms, controller resets.
As shown in Figure 4, D/A converting circuit comprises LTC2622 digital to analog converter, triode Q4, amplifier U2A, slide rheostat RP1 and resistance R 7; The the 1st, the 2nd and the 3rd pin of LTC2622 digital to analog converter is all electrically connected to controller, the 4th pin is connected with power supply VCC by resistance R 7, the 4th pin is electrically connected to the emitter of triode Q4, the grounded collector of triode Q4, the 5th pin is electrically connected to the in-phase input end of slide rheostat RP1 one end and amplifier U2A respectively, the equal ground connection of the other end of slide rheostat RP1 and centre tap, the inverting input of amplifier U2A and output terminal are all electrically connected to the input end of constant-current source circuit.
As shown in Figure 5, analog to digital conversion circuit comprises TLC2552 analog to digital converter, resistance R 6 and triode Q3; The the 1st, the 7th and the 8th pin of TLC2552 analog to digital converter is all electrically connected to controller, the the 4th and the 5th pin is all electrically connected to the output terminal of constant-current source circuit, the 2nd pin is electrically connected to one end of resistance R 6 and the emitter of triode Q3 respectively, the grounded collector of triode Q3, another termination power of R6 VCC.
Keyboard is 4 * 4 keyboards, comprises 0 to 9 digital input key, increases and builds, reduces and build, arrange key, acknowledgement key, # keyboard and cancel key.Display is LCD1602 liquid crystal display.Controller is AT89S52 single-chip microcomputer.Sampling resistor is health copper-manganese resistance wire.
The utility model is by the preset output current value of keyboard, and controller is exported corresponding digital signal to D/A converting circuit, and D/A converting circuit outputting analog signal, to constant-current source circuit, is controlled the size of current of output.Electric current in load is sampled and is become voltage signal by sampling resistor again, analog to digital conversion circuit by signal feedback in controller, controller, by feedback signal and prevalue comparison, is adjusted output current signal size according to difference between the two, and the current value of output shows by display screen.
The utlity model has following features:
Output current adjustable extent is 200～2000mA, output dc voltage≤10V; Display shows output current value; There is "+" "-" step by step modulating function, ripple current≤2mA.
Should be understood that the present embodiment is only not used in restriction scope of the present utility model for the utility model is described.In addition should be understood that those skilled in the art can make various changes or modifications the utility model after having read the content of the utility model instruction, these equivalent form of values fall within the application's appended claims limited range equally.
Claims (9)
1. a Digital Control Direct Current Source, it is characterized in that, comprise controller (1), keyboard (2), display (3), analog to digital conversion circuit (4), D/A converting circuit (5), the constant-current source circuit (6) that comprises sampling resistor and electric current output interface (7); Described controller is electrically connected to keyboard, display, analog to digital conversion circuit and D/A converting circuit respectively, the output terminal of analog-digital conversion circuit as described and the input end of D/A converting circuit are electrically connected to constant-current source circuit respectively, and described constant-current source circuit is electrically connected to electric current output interface.
2. Digital Control Direct Current Source according to claim 1, is characterized in that, described constant-current source circuit comprises LM358AN amplifier, OP07Z amplifier, and resistance R 1, R2, R3, R4, R5 and triode Q1, Q2, described sampling resistor is RS; The in-phase input end of OP07Z amplifier is electrically connected to the input end of analog to digital conversion circuit by resistance R 1, the inverting input of OP07Z amplifier is electrically connected to the output terminal of LM358AN amplifier and one end of resistance R 4 respectively, the output terminal of OP07Z amplifier is electrically connected to the base stage of triode Q1, the emitter of Q1 is electrically connected to the base stage of triode Q2, and the collector of triode Q1 and triode Q2 is all electrically connected to electric current output interface; The R4 other end is electrically connected to inverting input and R5 one end of LM358AN amplifier respectively, the in-phase input end of LM358AN amplifier is electrically connected to one end of resistance R 2 and resistance R 3 respectively, resistance R 2 other end ground connection, resistance R 3 other ends are electrically connected to emitter and resistance R S one end of triode Q2 respectively, and the resistance R S other end and resistance R 5 other ends are electrically connected to and ground connection.
3. Digital Control Direct Current Source according to claim 1, is characterized in that, also comprises crystal oscillating circuit (8) and reset circuit (9), and described crystal oscillating circuit and reset circuit are electrically connected to controller respectively.
4. Digital Control Direct Current Source according to claim 1, is characterized in that, described D/A converting circuit comprises LTC2622 digital to analog converter, triode Q4, amplifier U2A, slide rheostat RP1 and resistance R 7; The the 1st, the 2nd and the 3rd pin of described LTC2622 digital to analog converter is all electrically connected to controller, the 4th pin is connected with power supply VCC by resistance R 7, the 4th pin is electrically connected to the emitter of triode Q4, triode Q4 grounded collector, the 5th pin is electrically connected to the in-phase input end of slide rheostat RP1 one end and amplifier U2A respectively, the equal ground connection of the other end of slide rheostat RP1 and centre tap, the inverting input of amplifier U2A and output terminal are all electrically connected to the input end of constant-current source circuit.
5. Digital Control Direct Current Source according to claim 1, is characterized in that, analog-digital conversion circuit as described comprises TLC2552 analog to digital converter, resistance R 6 and triode Q3; The the 1st, the 7th and the 8th pin of TLC2552 analog to digital converter is all electrically connected to controller, the the 4th and the 5th pin is all electrically connected to the output terminal of constant-current source circuit, the 2nd pin is electrically connected to one end of resistance R 6 and the emitter of triode Q3 respectively, the grounded collector of triode Q3, another termination power of R6 VCC.
6. according to the Digital Control Direct Current Source described in claim 1 or 2 or 3 or 4 or 5, it is characterized in that, described keyboard is 4 * 4 keyboards, comprises 0 to 9 digital input key, increases and builds, reduces and build, arrange key, acknowledgement key, # keyboard and cancel key.
7. according to the Digital Control Direct Current Source described in claim 1 or 2 or 3 or 4 or 5, it is characterized in that, display is LCD1602 liquid crystal display.
8. according to the Digital Control Direct Current Source described in claim 1 or 2 or 3 or 4 or 5, it is characterized in that, controller is AT89S52 single-chip microcomputer.
9. according to the Digital Control Direct Current Source described in claim 1 or 2 or 3 or 4 or 5, it is characterized in that, sampling resistor is health copper-manganese resistance wire.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420083783.XU CN203838587U (en) | 2014-02-26 | 2014-02-26 | Numerical-control direct current source |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420083783.XU CN203838587U (en) | 2014-02-26 | 2014-02-26 | Numerical-control direct current source |
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| CN203838587U true CN203838587U (en) | 2014-09-17 |
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| CN201420083783.XU Expired - Fee Related CN203838587U (en) | 2014-02-26 | 2014-02-26 | Numerical-control direct current source |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104331113A (en) * | 2014-10-14 | 2015-02-04 | 苏州工业职业技术学院 | High-precision numerically-controlled constant current source |
| CN104503337A (en) * | 2014-12-31 | 2015-04-08 | 桂林铭瑶电子科技有限公司 | Numerically controlled constant current source circuit based on DSP |
| CN104536323A (en) * | 2014-12-31 | 2015-04-22 | 桂林铭瑶电子科技有限公司 | Numerical control constant-current source device based on ARM9 |
| CN105912061A (en) * | 2016-06-08 | 2016-08-31 | 江苏南瓷绝缘子股份有限公司 | Digitally controlled direct-current stabilized voltage power supply |
| CN107124800A (en) * | 2017-06-28 | 2017-09-01 | 苏州标品杰电子科技有限公司 | A kind of PLC technology Switching Power Supply |
| CN112835406A (en) * | 2021-03-10 | 2021-05-25 | 京东方科技集团股份有限公司 | Constant current source circuit, driving method thereof and current control device |
| CN114487691A (en) * | 2021-12-08 | 2022-05-13 | 中国人民解放军火箭军工程大学 | Portable cable conduction insulation detection device |
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2014
- 2014-02-26 CN CN201420083783.XU patent/CN203838587U/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104331113A (en) * | 2014-10-14 | 2015-02-04 | 苏州工业职业技术学院 | High-precision numerically-controlled constant current source |
| CN104503337A (en) * | 2014-12-31 | 2015-04-08 | 桂林铭瑶电子科技有限公司 | Numerically controlled constant current source circuit based on DSP |
| CN104536323A (en) * | 2014-12-31 | 2015-04-22 | 桂林铭瑶电子科技有限公司 | Numerical control constant-current source device based on ARM9 |
| CN105912061A (en) * | 2016-06-08 | 2016-08-31 | 江苏南瓷绝缘子股份有限公司 | Digitally controlled direct-current stabilized voltage power supply |
| CN107124800A (en) * | 2017-06-28 | 2017-09-01 | 苏州标品杰电子科技有限公司 | A kind of PLC technology Switching Power Supply |
| CN107124800B (en) * | 2017-06-28 | 2019-04-16 | 苏州标品杰电子科技有限公司 | A kind of PLC technology Switching Power Supply |
| CN112835406A (en) * | 2021-03-10 | 2021-05-25 | 京东方科技集团股份有限公司 | Constant current source circuit, driving method thereof and current control device |
| CN112835406B (en) * | 2021-03-10 | 2022-12-09 | 京东方科技集团股份有限公司 | Constant current source circuit, driving method thereof and current control device |
| CN114487691A (en) * | 2021-12-08 | 2022-05-13 | 中国人民解放军火箭军工程大学 | Portable cable conduction insulation detection device |
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| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140917 Termination date: 20150226 |
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| EXPY | Termination of patent right or utility model |