CN102929320A - High-precision DC constant-current source - Google Patents
High-precision DC constant-current source Download PDFInfo
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- CN102929320A CN102929320A CN2012104726884A CN201210472688A CN102929320A CN 102929320 A CN102929320 A CN 102929320A CN 2012104726884 A CN2012104726884 A CN 2012104726884A CN 201210472688 A CN201210472688 A CN 201210472688A CN 102929320 A CN102929320 A CN 102929320A
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Abstract
The invention provides a high-precision DC constant-current source and belongs to the technical field of spatial measurement. The DC constant-current source comprises a power supply circuit, an adjustment circuit, a sampling circuit, an error magnification and feedback circuit and a reference voltage UC, as well as a load resistor R connected with the DC constant-current source, wherein the power supply circuit comprises a transformer, a diode D1, a diode D2, a three-terminal voltage-stabilized source chip IC, a capacitor C1 and a capacitor C2; the adjustment circuit comprises a triode Q1, a triode Q2, a resistor R1 and a capacitor C3; the error magnification and feedback circuit comprises operational amplifiers UIA and UIB and a resistor R3; and the sampling circuit comprises a resistor R2 and a sampling resistor Rs. The DC constant-current source can provide low-current and high-precision constant DC current for a load and can also provide constant-current excitation for weak signals generated by space particles in the space so as to realize measurement of the weak signals.
Description
Technical field
The present invention relates to a kind of high precision dc constant current power supply, belong to the space measurement technical field.
Background technology
In the space exploration technology, weak signal is usually covered by other signal, need high precision, highly reliable acquisition system that it is measured, particularly need the relatively high power supply of precision and degree of stability that voltage signal is provided, the error that the measurement of change is caused to eliminate voltage fluctuation.Constant current source is one of effective ways that address this problem, but traditional precision constant current source is made of transistor, although circuit design is simple, precision is high, but the variation of the supply voltage of this constant current source can affect the output current size, and the variation of load is also larger on the impact of constant current source, has affected to a certain extent its range of application.Therefore, float little steady current for high precision, temperature can be provided, realize the measurement of weak signal, change, a kind of precision constant current source need to be provided, described constant current source will be eliminated supply voltage and load variations as much as possible to the influence of peak current.
Summary of the invention
Measurement problem for weak signal in the space technology, the invention provides a kind of high precision dc constant current power supply, described dc constant current power supply can provide little electric current, high-precision Constant Direct Current electric current for load, and the weak signal that Space Particle is produced in the space provides constant current drive, realizes weak signal measurement.
The objective of the invention is to be achieved through the following technical solutions.
A kind of high precision dc constant current power supply, described dc constant current power supply comprises: power circuit, Circuit tuning, sample circuit, error amplification and feedback circuit, reference voltage U
C, and the pull-up resistor R that is connected with described dc constant current power supply; Wherein power circuit comprises transformer, diode D1, diode D2, three-terminal voltage-stabilizing power supply chip IC, capacitor C 1, capacitor C 2; Circuit tuning comprises triode Q1, triode Q2, resistance R 1, capacitor C 3; Error is amplified and feedback circuit comprises operational amplifier UIA, UIB, resistance R 3; Sample circuit comprises resistance R
2, sample resistance Rs;
The annexation of described dc constant current power supply each several part is as follows:
Transformer one termination input voltage, the other end connects respectively the anode of diode D1, D2; The negative electrode of diode D1, D2 and connect after, be connected with the input end of three-terminal voltage-stabilizing power supply chip IC; Three-terminal voltage-stabilizing power supply chip IC's is ground wire grounded, and the output terminal of three-terminal voltage-stabilizing power supply chip IC is connected collector with the collector of triode Q2 respectively and is connected with triode Q1; The emitter of triode Q1 is connected base stage and is connected with triode Q2, between the output terminal of three-terminal voltage-stabilizing power supply chip IC and ground wire and connect capacitor C 1 and capacitor C 2;
The end of sample resistance Rs is connected with an end of resistance R 2, the other end of resistance R 2 is connected with the in-phase end of operational amplifier UIB, the end of oppisite phase of operational amplifier UIB is connected with an end of resistance R 3, the other end of resistance R 3 is with after the output terminal of operational amplifier UIB is connected, be connected the in-phase end of operational amplifier UIA and reference voltage U with the end of oppisite phase of operational amplifier UIA
COutput terminal connect, the output terminal of operational amplifier UIA is connected with an end of resistance R 1, the other end of resistance R 1 is connected the other end of capacitor C 3, reference voltage U with after the base stage of triode Q1 is connected with an end of capacitor C 3
CInput end and the other end ground connection of sample resistance Rs;
The end of pull-up resistor R is connected with the emitter of triode Q2, and the other end of pull-up resistor R is connected with sample resistance Rs with resistance R 2 respectively.
Wherein, acting as of power circuit realizes voltage stabilizing, rectification and filtering to input voltage, obtains constant voltage;
Acting as of Circuit tuning fed back and adjusted the constant current source output current, obtains steady current;
Acting as of sample circuit produces pressure drop by sample resistance Rs;
Acting as of error amplification and feedback circuit, the pressure drop and the reference voltage U that between operational amplifier UIA, UIB and resistance R 3, sample resistance Rs are produced
cCarry out feedback ratio, obtain voltage difference;
Acting as of reference voltage produces constant reference voltage, and the pressure drop that produces with sample resistance compares, and reduces simultaneously voltage noise;
The course of work of described dc constant current power supply is as follows:
The voltage of input by diode D1, D2 rectification, after then process three-terminal voltage-stabilizing power supply chip IC and capacitor C 1, capacitor C 2 are carried out voltage stabilizing, obtains galvanic current and presses behind transformer pressure-reducing; The electric current that sample resistance Rs obtains produces pressure drop through after the resistance R 2, is input to the in-phase end of operational amplifier UIB; After the end of oppisite phase of operational amplifier UIB carries out close-loop feedback by resistance R 3, the upper pressure drop that produces of sample resistance Rs is input to the end of oppisite phase of operational amplifier UIA; Upper pressure drop and the reference voltage that produces of sample resistance Rs compared, obtain voltage difference, described voltage difference is through resistance R 1, base stage in the triode Q1 first order produces base current, after the amplification through the triode Q1 second level, obtain constant electric current, i.e. output current at pull-up resistor R.
Preferred described reference voltage comprises 78L15 type reference voltage chip UC, precision resistance Rc, capacitor C 4; Wherein an end of capacitor C 4 is connected with 3 pin of reference voltage chip, is reference voltage output end; The other end of capacitor C 4 is connected with 4 pin of reference voltage chip, and 3 pin of reference voltage chip connect+15V voltage by precision resistance Rc.
Beneficial effect
1. the invention provides in a kind of high precision dc constant current power supply, because an operational amplifier can not satisfy the gain requirement of feedback, error in the described dc constant current power supply is amplified and feedback circuit uses two operational amplifiers simultaneously, consists of close-loop feedback, can improve input impedance; Specifically, sample circuit is at sample resistance R
sUpper generation pressure drop by being connected into the first order homophase operational amplifier UIB of closed loop, compares differential pressure Δ U of generation to second level rp-op amp UIA and reference voltage, through a resistance R
1Form a base current in triode first order base stage, amplify through second level emitter again the constant current source output current is controlled, produce high-precision direct current steady current at pull-up resistor R, for further implementation space weak signal is provided by a kind of Constant Current-Source Design mode that provides.
2. the invention provides a kind of high precision dc constant current power supply, reference voltage in the described dc constant current power supply is by the lower reference voltage chip of serviceability temperature coefficient, and at electric capacity of its two ends parallel connection, again by precision resistance design mix volt circuit, to obtain constant reference voltage.Because electric capacity in parallel can make noise voltage significantly reduce.
3. in described high precision dc constant current power supply, sample resistance Rs adopts the manganese-copper filament wire-wound resistor, and this temperature-coefficient of electrical resistance is little, can reach 10
-6/ ℃.Described sample resistance good stability requires it larger with extraneous contact area simultaneously, even also can very fast heat radiation by large electric current, can further reduce the impact that temperature drift brings.
Description of drawings
Fig. 1 is the circuit diagram of high precision dc constant current power supply of the present invention.
Fig. 2 is the circuit diagram of described reference voltage.
Bias state schematic diagram when Fig. 3 is the described radiosensitive field effect transistor of embodiment (RadFET) reading out data.
Embodiment
Below by embodiment, the present invention is further described.
Embodiment
High precision dc constant current power supply as shown in Figure 1, described dc constant current power supply comprises: power circuit, Circuit tuning, sample circuit, error amplification and feedback circuit, reference voltage U
C, and the pull-up resistor R that is connected with described dc constant current power supply; Wherein power circuit comprises transformer, diode D1, diode D2, three-terminal voltage-stabilizing power supply chip IC, capacitor C 1, capacitor C 2; Circuit tuning comprises triode Q1, triode Q2, resistance R 1, capacitor C 3; Error is amplified and feedback circuit comprises operational amplifier UIA, UIB, resistance R 3; Sample circuit comprises resistance R
2, sample resistance Rs;
Wherein, the model of diode D1, D2 is 5401, the model of triode Q1, Q2 is 2N3906, the model of three-terminal voltage-stabilizing power supply chip IC is 78L15, the model of operational amplifier is OP07, capacitor C 1=4700 μ F, C2=C3=0.1 μ F, C4=100 μ F, resistance R 1=200 Ω, R2=910 Ω, R3=910 Ω; Sample resistance Rs adopts the manganese-copper filament wire-wound resistor, and resistance is 100 Ω.
The annexation of described dc constant current power supply each several part is as follows:
Transformer one termination input voltage, the other end connects respectively the anode of diode D1, D2; The negative electrode of diode D1, D2 and connect after, be connected with the input end of three-terminal voltage-stabilizing power supply chip IC; Three-terminal voltage-stabilizing power supply chip IC's is ground wire grounded, and the output terminal of three-terminal voltage-stabilizing power supply chip IC is connected collector with the collector of triode Q2 respectively and is connected with triode Q1; The emitter of triode Q1 is connected base stage and is connected with triode Q2, between the output terminal of three-terminal voltage-stabilizing power supply chip IC and ground wire and connect capacitor C 1 and capacitor C 2;
The end of sample resistance Rs is connected with an end of resistance R 2, the other end of resistance R 2 is connected with the in-phase end of operational amplifier UIB, the end of oppisite phase of operational amplifier UIB is connected with an end of resistance R 3, the other end of resistance R 3 is with after the output terminal of operational amplifier UIB is connected, be connected the in-phase end of operational amplifier UIA and reference voltage U with the end of oppisite phase of operational amplifier UIA
COutput terminal connect, the output terminal of operational amplifier UIA is connected with an end of resistance R 1, the other end of resistance R 1 is connected the other end of capacitor C 3, reference voltage U with after the base stage of triode Q1 is connected with an end of capacitor C 3
CInput end and the other end ground connection of sample resistance Rs;
The end of pull-up resistor R is connected with the emitter of triode Q2, and the other end of pull-up resistor R is connected with sample resistance Rs with resistance R 2 respectively.
The course of work of described dc constant current power supply is as follows:
The voltage of input by diode D1, D2 rectification, after then process three-terminal voltage-stabilizing power supply chip IC and capacitor C 1, capacitor C 2 are carried out voltage stabilizing, obtains galvanic current and presses behind transformer pressure-reducing; The electric current that sample resistance Rs obtains produces pressure drop through after the resistance R 2, is input to the in-phase end of operational amplifier UIB; After the end of oppisite phase of operational amplifier UIB carries out close-loop feedback by resistance R 3, the upper pressure drop that produces of sample resistance Rs is input to the end of oppisite phase of operational amplifier UIA; Upper pressure drop and the reference voltage that produces of sample resistance Rs compared, obtain voltage difference, described voltage difference is through resistance R 1, base stage in the triode Q1 first order produces base current, after the amplification through the triode Q1 second level, obtain constant electric current, i.e. output current at pull-up resistor R.
Wherein, reference voltage comprises 78L15 type reference voltage chip UC, precision resistance Rc, capacitor C 4; Wherein an end of capacitor C 4 is connected with 3 pin of reference voltage chip, is reference voltage output end; The other end of capacitor C 4 is connected with 4 pin of reference voltage chip, and 3 pin of reference voltage chip connect+15V voltage by precision resistance Rc, as shown in Figure 2.
In the space exploration, the degree of fluctuation of supply voltage will have a strong impact on the degree of accuracy of weak signal monitoring, need constant power supply to provide stable power supply signal for it, to eliminate power supply signal to the interference of measured signal.Take RadFET as example, in radiation dose is surveyed, in order to eliminate supply voltage to the impact of RadFET threshold voltage, adopt high precision dc constant current power supply of the present invention to power to RadFET.As shown in Figure 3, wherein S, B, G, D represent respectively source electrode, substrate, grid and the drain electrode of RadFET; The transformer input voltage is Vss, and the described high precision dc constant current power supply course of work is as follows,
Step 1, the source electrode with RadFET, drain electrode, substrate and grid be ground connection all, by radiation source RadFET is carried out irradiation, by the data reading circuit that is connected with source electrode, obtains the predose drain-source voltage V of RadFET
DS0
Step 2, with the drain and gate of RadFET ground connection all, substrate is connected with the emitter of triode Q2 after being connected with source electrode, with the pull-up resistor R of RadFET as described high precision dc constant current power supply, to provide under the condition of constant current source at source electrode, by the data reading circuit that is connected with source electrode, obtain the drain-source voltage V behind the irradiation of RadFET
DS, with the drain-source voltage V behind the irradiation
DSDeduct the drain-source voltage V of predose
DS0, the difference that obtains is threshold drift voltage Δ V
Th
Step 3, by formula Δ V
Th=a * D
b, obtain the mutual relationship between threshold voltage and the radiation dose.Wherein, a, b are coefficient, and be relevant with the performance of RadFET; D is radiation dose, can measure by experiment.Because Δ V
ThAll can obtain by experiment with D, therefore can be by described high precision dc constant current power supply, the performance of test RadFET.
In sum, above is preferred embodiment of the present invention only, is not for limiting protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (3)
1. high precision dc constant current power supply, it is characterized in that: described dc constant current power supply comprises: power circuit, Circuit tuning, sample circuit, error amplification and feedback circuit, reference voltage U
C, and the pull-up resistor R that is connected with described dc constant current power supply; Wherein power circuit comprises transformer, diode D1, diode D2, three-terminal voltage-stabilizing power supply chip IC, capacitor C 1, capacitor C 2; Circuit tuning comprises triode Q1, triode Q2, resistance R 1, capacitor C 3; Error is amplified and feedback circuit comprises operational amplifier UIA, UIB, resistance R 3; Sample circuit comprises resistance R
2, sample resistance Rs;
The annexation of described dc constant current power supply each several part is as follows:
Transformer one termination input voltage, the other end connects respectively the anode of diode D1, D2; The negative electrode of diode D1, D2 and connect after, be connected with the input end of three-terminal voltage-stabilizing power supply chip IC; Three-terminal voltage-stabilizing power supply chip IC's is ground wire grounded, and the output terminal of three-terminal voltage-stabilizing power supply chip IC is connected collector with the collector of triode Q2 respectively and is connected with triode Q1; The emitter of triode Q1 is connected base stage and is connected with triode Q2, between the output terminal of three-terminal voltage-stabilizing power supply chip IC and ground wire and connect capacitor C 1 and capacitor C 2;
The end of sample resistance Rs is connected with an end of resistance R 2, the other end of resistance R 2 is connected with the in-phase end of operational amplifier UIB, the end of oppisite phase of operational amplifier UIB is connected with an end of resistance R 3, the other end of resistance R 3 is with after the output terminal of operational amplifier UIB is connected, be connected the in-phase end of operational amplifier UIA and reference voltage U with the end of oppisite phase of operational amplifier UIA
COutput terminal connect, the output terminal of operational amplifier UIA is connected with an end of resistance R 1, the other end of resistance R 1 is connected the other end of capacitor C 3, reference voltage U with after the base stage of triode Q1 is connected with an end of capacitor C 3
CInput end and the other end ground connection of sample resistance Rs;
The end of pull-up resistor R is connected with the emitter of triode Q2, and the other end of pull-up resistor R is connected with sample resistance Rs with resistance R 2 respectively.
2. a kind of high precision dc constant current power supply according to claim 1, it is characterized in that: described reference voltage comprises 78L15 type reference voltage chip UC, precision resistance Rc, capacitor C 4; Wherein an end of capacitor C 4 is connected with 3 pin of reference voltage chip, is reference voltage output end; The other end of capacitor C 4 is connected with 4 pin of reference voltage chip, and 3 pin of reference voltage chip connect+15V voltage by precision resistance Rc.
3. a kind of high precision dc constant current power supply according to claim 2, it is characterized in that: the model of diode D1, D2 is 5401, the model of triode Q1, Q2 is 2N3906, the model of three-terminal voltage-stabilizing power supply chip IC is 78L15, the model of operational amplifier is OP07, capacitor C 1=4700 μ F, C2=C3=0.1 μ F, C4=100 μ F, resistance R 1=200 Ω, R2=910 Ω, R3=910 Ω; Sample resistance Rs adopts the manganese-copper filament wire-wound resistor, and resistance is 100 Ω.
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| CN2012104726884A CN102929320A (en) | 2012-11-20 | 2012-11-20 | High-precision DC constant-current source |
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Cited By (9)
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| CN103427683A (en) * | 2013-08-30 | 2013-12-04 | 昆山奥德鲁自动化技术有限公司 | Voltage-stabilizing power circuit |
| CN103457488A (en) * | 2013-09-12 | 2013-12-18 | 昆山新金福精密电子有限公司 | Series voltage stabilizing circuit |
| CN104076853A (en) * | 2014-05-29 | 2014-10-01 | 北京航天自动控制研究所 | Constant-current source circuit |
| CN104407660A (en) * | 2014-11-14 | 2015-03-11 | 航天长峰朝阳电源有限公司 | Online integration high-precision constant current source |
| CN105388952A (en) * | 2015-12-29 | 2016-03-09 | 吉林大学 | Two-way constant current source circuit |
| CN105425884A (en) * | 2015-12-29 | 2016-03-23 | 吉林大学 | Bi-directional constant current source device based on dual negative feedback control |
| CN105528009A (en) * | 2015-12-29 | 2016-04-27 | 吉林大学 | Portable bi-directional constant current source module |
| CN108918800A (en) * | 2018-05-16 | 2018-11-30 | 佛山市云米电器科技有限公司 | Water hardness detector, the hydrotreater, method of adjustment of adjustable filtering parameter |
| CN110986913A (en) * | 2019-12-13 | 2020-04-10 | 西安航天精密机电研究所 | Method and circuit system for shortening low-temperature starting time of optical fiber gyroscope |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103427683A (en) * | 2013-08-30 | 2013-12-04 | 昆山奥德鲁自动化技术有限公司 | Voltage-stabilizing power circuit |
| CN103457488A (en) * | 2013-09-12 | 2013-12-18 | 昆山新金福精密电子有限公司 | Series voltage stabilizing circuit |
| CN103457488B (en) * | 2013-09-12 | 2015-10-21 | 昆山新金福精密电子有限公司 | A kind of serial voltage regulation circuit |
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| CN104407660A (en) * | 2014-11-14 | 2015-03-11 | 航天长峰朝阳电源有限公司 | Online integration high-precision constant current source |
| CN104407660B (en) * | 2014-11-14 | 2016-04-13 | 航天长峰朝阳电源有限公司 | Online integrated high precision constant current source |
| CN105388952A (en) * | 2015-12-29 | 2016-03-09 | 吉林大学 | Two-way constant current source circuit |
| CN105425884A (en) * | 2015-12-29 | 2016-03-23 | 吉林大学 | Bi-directional constant current source device based on dual negative feedback control |
| CN105528009A (en) * | 2015-12-29 | 2016-04-27 | 吉林大学 | Portable bi-directional constant current source module |
| CN108918800A (en) * | 2018-05-16 | 2018-11-30 | 佛山市云米电器科技有限公司 | Water hardness detector, the hydrotreater, method of adjustment of adjustable filtering parameter |
| CN110986913A (en) * | 2019-12-13 | 2020-04-10 | 西安航天精密机电研究所 | Method and circuit system for shortening low-temperature starting time of optical fiber gyroscope |
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Application publication date: 20130213 |