CN102006014A - Weak current amplification circuit with high dynamic range for space photoelectric measurement instrument - Google Patents
Weak current amplification circuit with high dynamic range for space photoelectric measurement instrument Download PDFInfo
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- CN102006014A CN102006014A CN 201010529559 CN201010529559A CN102006014A CN 102006014 A CN102006014 A CN 102006014A CN 201010529559 CN201010529559 CN 201010529559 CN 201010529559 A CN201010529559 A CN 201010529559A CN 102006014 A CN102006014 A CN 102006014A
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Abstract
The invention discloses a weak current amplification circuit with a high dynamic range for a space photoelectric measurement instrument, relating to the field of electronics and solving the problem of the switching of the large-range amplification of a week current signal of the space photoelectric measurement instrument. The weak current amplification circuit comprises a first-stage amplification circuit, a second-stage amplification circuit and a third-stage amplification circuit, as well as a first analogue switch, a second analogue switch and a third analogue switch, wherein a week current signal input end is connected with the input end of the first-stage amplification circuit, the output end of the first-stage amplification circuit is respectively connected with the input end of the second-stage amplification circuit and the signal input end of the first analogue switch, the output end of the second-stage amplification circuit is respectively connected with the input end of the third-stage amplification circuit and the signal input end of the second analogue switch, the output end of the third-stage amplification circuit is connected with the signal input end of the third analogue switch, and the signal output ends of the first analogue switch, the second analogue switch and the third analogue switch are connected with a signal output end at the same time.
Description
Technical field
The present invention relates to person in electronics, be specifically related to the weak current signal amplification circuit in the great dynamic range photoelectric measurement instrument of a kind of Aeronautics and Astronautics usefulness space.
Background technology
At present, the weak current amplifying circuit is the core part of photoelectric measurement instrument, and numerous great dynamic range photoelectric measurement instrument circuit mainly comprise: amplifier, i.e. preamplifier, main amplifier, digital processing circuit etc.Carry out the measurement of great dynamic range signal input, must change the multiplication factor of amplifier, and the multiplication factor of amplifier is to realize by the feedback resistance that changes amplifier.Therefore, the big excursion resistance switching of feedback resistance is a core component of realizing photoelectric measurement instrument kinetic measurement function on a large scale.
On the ground in the photoelectric measurement instrument of Ying Yonging, the resistance of amplifier feedback resistance can adopt relay to switch to change, to change the multiplication factor of amplifier.But in the spatial light electric measuring instrument was used, there was life problems in relay, and frequent multiplication factor changes operation can make relay contact reach the life-span inefficacy very soon, influences the normal operation of instrument; And, after relay lost efficacy, can't repair and replacement; Therefore, relay can not satisfy the instructions for use of space apparatus long-life, high reliability.Though the handoff functionality of the alternative relay of analog switch, it can not accomplish the resistance infinity when disconnecting, can influence the complete machine performance index, thereby limit its application in the spatial light electric measuring instrument.
Summary of the invention
The present invention realizes the problem of range switch circuit difficulty on a large scale for low current amplifier in the solution existing space photoelectric measurement instrument, and a kind of great dynamic range weak current amplifying circuit that is used for the spatial light electric measuring instrument is provided.
A kind of great dynamic range weak current amplifying circuit that is used for the spatial light electric measuring instrument comprises first order amplifying circuit, second level amplifying circuit and third level amplifying circuit, and it also comprises first analog switch, second analog switch and the 3rd analog switch; The weak current signal input part is connected with the input of described first order amplifying circuit, and the output of described first order amplifying circuit is connected with the input of second level amplifying circuit, the signal input part of first analog switch respectively; The output of described second level amplifying circuit is connected with the input of third level amplifying circuit, the signal input part of second analog switch respectively, and the output of third level amplifying circuit is connected with the signal input part of the 3rd analog switch; The signal output part of the signal output part of the signal output part of described first analog switch, second analog switch and the 3rd analog switch is connected with signal output part simultaneously.
Operation principle of the present invention: the present invention adopts the on a large scale switching controls of analog switch to weak current signal amplification circuit range in the photoelectric measurement; Realized the high-performance of great dynamic range weak current is amplified, described weak current signal is by after the amplification of first order amplifying circuit, be converted to voltage signal, magnitude of voltage of output output and the proportional voltage signal of input current signal at described first order amplifying circuit, and this voltage signal is connected to the signal input part of first analog switch as an optional range signal, the weak current signal inversion of the output of described first order amplifying circuit and input, and be connected with the positive input terminal of second amplifier in the amplifying circuit of the second level; Described second level amplifying circuit is the ratio amplifying circuit, and the voltage signal of the output of first order amplifying circuit is further amplified; The output of second level amplifying circuit and input homophase, the voltage signal of output is connected to the signal input part of second analog switch as an optional range signal, and the output of second level amplifying circuit is connected to the positive input terminal of the 3rd amplifier of third level amplifying circuit; Described third level amplifying circuit is the ratio amplifying circuit, output voltage signal to second level amplifying circuit further amplifies, the output of described third level amplifying circuit and input homophase, same voltage signal with output is connected to the input of the 3rd analog switch as an optional range signal.
Described each analog switch is controlled by address signal, selects the signal of the signal input part of some analog switches according to the size of weak current signal of input, is connected to output signal end then.And the signal of the input of other two analog switches and output disconnect, and do not influence the size of output signal, also can not change the operating state of first order amplifying circuit, second level amplifying circuit and third level amplifying circuit.
Beneficial effect of the present invention: the present invention adopts three analog switches that the output of three amplifying circuits that are cascaded is switched, and has realized the switching controls on a large scale of weak current signal amplification circuit range in the photoelectric measurement; Described analog switch is connected the output of amplifying circuit, gating is carried out in the output of three amplifying circuits switch, rather than be connected in the feedback loop of amplifying circuit, has avoided the analog switch leakage current to the amplifying circuit Effect on Performance; Control by address signal, realized the soft handover control of circuit, device of the present invention does not contain the mechanical action element, and response speed is fast, and circuit structure is simple, and loss is little, and the life-span is long, and noise jamming is little, the reliability height; Apparatus of the present invention are a kind of multiplication factor switching controls great dynamic range weak current amplifying circuits flexibly.
Description of drawings
Fig. 1 is a kind of structural representation that is used for the great dynamic range weak current amplifying circuit of spatial light electric measuring instrument of the present invention;
Fig. 2 is a kind of circuit theory diagrams that are used for the great dynamic range weak current amplifying circuit of spatial light electric measuring instrument of the present invention.
Among the figure: 1, first amplifier, 2, second amplifier, 3, the 3rd amplifier, 4, first analog switch, 5, second analog switch, 6, the 3rd analog switch, 7, first order amplifying circuit, 8, second level amplifying circuit, 9, third level amplifying circuit, A, weak current signal input part, B, signal output part.
Embodiment
Embodiment one, present embodiment is described in conjunction with Fig. 1, a kind of great dynamic range weak current amplifying circuit that is used for the spatial light electric measuring instrument, comprise first order amplifying circuit 7, second level amplifying circuit 8 and third level amplifying circuit 9, it also comprises first analog switch 4, second analog switch 5 and the 3rd analog switch 6; Weak current signal input part A is connected with the input of described first order amplifying circuit 7, and the output of described first order amplifying circuit 7 is connected with the input of second level amplifying circuit 8, the signal input part of first analog switch 4 respectively; The output of described second level amplifying circuit 8 is connected with the input of third level amplifying circuit 9, the signal input part of second analog switch 5 respectively, and the output of third level amplifying circuit 9 is connected with the signal input part of the 3rd analog switch 6; The signal output part of the signal output part of the signal output part of described first analog switch 4, second analog switch 5 and the 3rd analog switch 6 is connected with signal output part B simultaneously.
Embodiment two, present embodiment and embodiment one described a kind of difference that is used for the great dynamic range weak current amplifying circuit of spatial light electric measuring instrument are, described first order amplifying circuit 7 comprises first amplifier 1, first resistance R 1, second resistance R 2 and the capacitor C, and described weak current signal input part A is connected with the negative input end of first amplifier 1 by first resistance R 1; One end of described second resistance R 2 is connected with weak current signal input part A, and the other end of second resistance R 2 is connected with the output of first amplifier 1, and the described capacitor C and second resistance R 2 are connected in parallel; The positive input terminal ground connection of described first amplifier 1; The positive input terminal of first amplifier 1 is as the input of first order amplifying circuit 7, and the output of first amplifier 1 is as the output of first order amplifying circuit 7.
The described first order amplifying circuit 7 of present embodiment is a current-voltage conversion circuit, and main effect is the weak current signal i to input
ACarry out integration, then according to certain proportionality coefficient with weak current signal i
ABe converted to voltage signal; When the resistance of described second resistance R 2 was big, the input signal that 7 pairs of amplitudes of first order amplifying circuit are very little carried out high-precision detection; The resistance of second resistance R 2 hour, 7 pairs of input signals of described first order amplifying circuit carry out Fast transforms.The parameter value of described second resistance R 2, capacitor C, first resistance R 1 is comprehensively determined according to response speed, conversion accuracy, the input signal amplitude of system.The output signal voltage u of described first order amplifying circuit 7
O1Weak current signal i with input
AThe pass be:
R in the formula
2Be the resistance of second resistance R 2, t is the time.
Embodiment three, present embodiment and embodiment one described a kind of difference that is used for the great dynamic range weak current amplifying circuit of spatial light electric measuring instrument are, described second level amplifying circuit 8 comprises second amplifier 2, the 3rd resistance R 3, the 4th resistance R 4 and the 5th resistance R 5, one end of described the 4th resistance R 4 is connected with the negative input end of second amplifier 2, the other end of the 4th resistance R 4 is connected with the end of the 3rd resistance R 3 with the 5th resistance R 5 simultaneously, the other end ground connection of described the 3rd resistance R 3, the other end of the 5th resistance R 5 is connected with the output of second amplifier 2; The positive input terminal of described second amplifier 2 is as the input of second level amplifying circuit 8, and the output of second amplifier 2 is as the output of second level amplifying circuit 8.
The described second level of present embodiment amplifying circuit 8 is the in-phase proportion amplifying circuit, and is described through second level amplifying circuit 8 output signal voltage u
O2Output signal voltage u with first order amplifying circuit 7
O1The pass be:
R in the formula
3Be the resistance of the 3rd resistance R 3, R
5It is the resistance of the 5th resistance R 5.
Embodiment four, present embodiment and embodiment one described a kind of difference that is used for the great dynamic range weak current amplifying circuit of spatial light electric measuring instrument are that described third level amplifying circuit 9 comprises the 3rd amplifier 3, the 6th resistance R 6, the 7th resistance R 7 and the 8th resistance R 8; One end of described the 7th resistance R 7 is connected with the negative input end of the 3rd amplifier 3, and the other end of the 4th resistance R 4 is connected with the output of the 6th resistance R 6 and the 8th resistance R 8 simultaneously; The other end ground connection of described the 6th resistance R 6, the other end of the 8th resistance R 8 is connected with the output of the 3rd amplifier 3; The positive input terminal of described the 3rd amplifier 3 is as the input of third level amplifying circuit 9, and the output of the 3rd amplifier 3 is as the output of third level amplifying circuit 9.
The described third level amplifying circuit 9 of present embodiment is the in-phase proportion amplifying circuit, third level amplification path output signal voltage u
O3With second level amplifying circuit 8 output signal voltage u
O2The pass be:
R in the formula
6Be the resistance of the 6th resistance R 6, R
8It is the resistance of the 8th resistance R 8.
Embodiment five, present embodiment are the embodiment of embodiment one:
The described weak current signal of present embodiment through twice amplification of second level amplifying circuit 8 and third level amplifying circuit 9, is obtained very high multiplication factor then through filtering, the amplification of first order amplifying circuit 7.Described three analog switches can select some signals in the output signal of first order amplifying circuit 7, second level amplifying circuit 8 and third level amplifying circuit 9 as the output signal of system, finally realize weak current signal i
AThe amplification of different multiples.
As input weak current signal i
AAmplitude hour, the amplitude of described first order amplifying circuit 7, second level amplifying circuit 8 output signals is too small relatively, do not satisfy the optimum valuing range of follow-up A/D conversion, and the output signal of third level amplifying circuit 9 compares with the output signal of second level amplifying circuit 8 with first order amplifying circuit 7 and has bigger amplitude, the output signal of third level amplifying circuit 9 can be obtained the voltage signal of more excellent precision property as the input of follow-up A/D conversion.Described analog switch is connected the output of third level amplifying circuit 9 under the address control signal effect with the input of the 3rd analog switch 6, the output of described the 3rd analog switch 6 is as signal output part B.
As input weak current signal i
AAmplitude when moderate, with described weak current signal i
ACompare with the optimum valuing range of follow-up A/D conversion, the amplitude of the output signal of described first order amplifying circuit 7 is too small, and the output signal amplitude of third level amplifying circuit 9 is excessive or saturated, has only the amplitude of second level amplifying circuit 8 output signals can satisfy the optimum valuing range of A/D conversion.Described second analog switch 5 is connected the output of second level amplifying circuit 8 under the address control signal effect with the signal input part of second analog switch 5, the output of described second analog switch 5 is as signal output part B.
As input weak current signal i
AAmplitude when big, with described weak current signal i
ACompare with the optimum valuing range of follow-up A/D conversion, the amplitude of described first order amplifying circuit 7 outputs just can satisfy the optimum valuing range of A/D conversion, and the amplitude of second level amplifying circuit 8, third level amplifying circuit 9 output signals is excessive, even can be saturated.Described first analog switch 4 is connected the output of first order amplifying circuit 7 under the address control signal effect with the input of first analog switch 4, the output of described first analog switch 4 is as signal output part B.
At any one constantly, analog switch can only select some signals of first order amplifying circuit 7, second level amplifying circuit 8, third level amplifying circuit 9 output signals as output signal.Described three analog switches switch the output signal of each amplifying circuit, the feedback loop of this process and amplifying circuit is irrelevant, having avoided the analog switch internal resistance value simultaneously is not the adverse effect of infinitely great this factor to systematic function, and switching noise is had very strong inhibitory action.Analog switch carries out gating to the output of amplifying circuit and switches, rather than be connected in the feedback loop of amplifying circuit, avoided the analog switch leakage current to the amplifying circuit Effect on Performance, in conjunction with Fig. 2, Ra is a zero-regulator resistor, is used for the signal resistance of input is returned to zero.
The described analog switch of present embodiment is an electronic device, and the model of described analog switch is AD7551, and controller CPU is according to input weak current signal i
AMagnitude range determine the multiplication factor scope of amplifying circuit, realize the signal of first order amplifying circuit 7, second level amplifying circuit 8,9 outputs of third level amplifying circuit gating respectively by address control signal.
The selection of described each parameter of present embodiment also needs further the requirement according to overall bandwidth, frequency and the multiplication factor of system, the combined input signal amplitude range, determine, and when practical application, adjust through Theoretical Calculation, the actual debugging of instrument according to test data.
The present invention is except the described content of the foregoing description, and the value of adoptable device parameters should be decided on concrete applicable cases.
Claims (4)
1. great dynamic range weak current amplifying circuit that is used for the spatial light electric measuring instrument, comprise first order amplifying circuit (7), second level amplifying circuit (8) and third level amplifying circuit (9), it is characterized in that it also comprises first analog switch (4), second analog switch (5) and the 3rd analog switch (6); Weak current signal input part (A) is connected with the input of described first order amplifying circuit (7), and the output of described first order amplifying circuit (7) is connected with the input of second level amplifying circuit (8), the signal input part of first analog switch (4) respectively; The output of described second level amplifying circuit (8) is connected with the input of third level amplifying circuit (9), the signal input part of second analog switch (5) respectively, and the output of third level amplifying circuit (9) is connected with the signal input part of the 3rd analog switch (6); The signal output part of the signal output part of the signal output part of described first analog switch (4), second analog switch (5) and the 3rd analog switch (6) is connected with signal output part (B) simultaneously.
2. a kind of great dynamic range weak current amplifying circuit that is used for the spatial light electric measuring instrument according to claim 1, it is characterized in that, described first order amplifying circuit (7) comprises first amplifier (1), first resistance (R1), second resistance (R2) and electric capacity (C), and described weak current signal input part (A) is connected with the negative input end of first amplifier (1) by first resistance (R1); One end of described second resistance (R2) is connected with weak current signal input part (A), and the other end of second resistance (R2) is connected with the output of first amplifier (1), and described electric capacity (C) is connected in parallel with second resistance (R2); The positive input terminal ground connection of described first amplifier (1); The negative input end of described first amplifier (1) is as the input of first order amplifying circuit (7), and the output of first amplifier (1) is as the output of first order amplifying circuit (7).
3. a kind of great dynamic range weak current amplifying circuit that is used for the spatial light electric measuring instrument according to claim 1, it is characterized in that, described second level amplifying circuit (8) comprises second amplifier (2), the 3rd resistance (R3), the 4th resistance (R4) and the 5th resistance (R5), one end of described the 4th resistance (R4) is connected with the negative input end of second amplifier (2), the other end of the 4th resistance (R4) is connected with the end of the 3rd resistance (R3) with the 5th resistance (R5) simultaneously, the other end ground connection of described the 3rd resistance (R3), the other end of the 5th resistance (R5) is connected with the output of second amplifier (2); The positive input terminal of described second amplifier (2) is as the input of second level amplifying circuit (8), and the output of second amplifier (2) is as the output of second level amplifying circuit (8).
4. a kind of great dynamic range weak current amplifying circuit that is used for the spatial light electric measuring instrument according to claim 1, it is characterized in that described third level amplifying circuit (9) comprises the 3rd amplifier (3), the 6th resistance (R6), the 7th resistance (R7) and the 8th resistance (R8); One end of described the 7th resistance (R7) is connected with the negative input end of the 3rd amplifier (3), and the other end of the 4th resistance (R4) is connected with the output of the 6th resistance (R6) with the 8th resistance (R8) simultaneously; The other end ground connection of described the 6th resistance (R6), the other end of the 8th resistance (R8) is connected with the output of the 3rd amplifier (3); The positive input terminal of described the 3rd amplifier (3) is as the input of third level amplifying circuit (9), and the output of the 3rd amplifier (3) is as the output of third level amplifying circuit (9).
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201010529559 CN102006014A (en) | 2010-11-03 | 2010-11-03 | Weak current amplification circuit with high dynamic range for space photoelectric measurement instrument |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201010529559 CN102006014A (en) | 2010-11-03 | 2010-11-03 | Weak current amplification circuit with high dynamic range for space photoelectric measurement instrument |
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| CN102006014A true CN102006014A (en) | 2011-04-06 |
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| CN 201010529559 Pending CN102006014A (en) | 2010-11-03 | 2010-11-03 | Weak current amplification circuit with high dynamic range for space photoelectric measurement instrument |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106441504A (en) * | 2016-11-09 | 2017-02-22 | 珠江水利委员会珠江水利科学研究院 | Linear frequency modulation continuous wave radar water level telemeasuring device and method |
| CN107342743A (en) * | 2016-12-16 | 2017-11-10 | 山东金洲科瑞节能科技有限公司 | A kind of signal coarse adjustment amplification control circuit |
| CN113125846A (en) * | 2021-04-16 | 2021-07-16 | 成都理工大学 | Weak current measuring system |
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| US5311353A (en) * | 1993-03-05 | 1994-05-10 | Analog Modules | Wide dynamic range optical receivers |
| CN1277753A (en) * | 1998-09-21 | 2000-12-20 | 皇家菲利浦电子有限公司 | Amplifier |
| US20030063354A1 (en) * | 2001-09-28 | 2003-04-03 | Andrew Davidson | Optical receiver including a dual gain path amplifier system |
| CN201181220Y (en) * | 2008-04-07 | 2009-01-14 | 中国科学院空间科学与应用研究中心 | Micro-current amplifier for spacing |
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2010
- 2010-11-03 CN CN 201010529559 patent/CN102006014A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5311353A (en) * | 1993-03-05 | 1994-05-10 | Analog Modules | Wide dynamic range optical receivers |
| CN1277753A (en) * | 1998-09-21 | 2000-12-20 | 皇家菲利浦电子有限公司 | Amplifier |
| US20030063354A1 (en) * | 2001-09-28 | 2003-04-03 | Andrew Davidson | Optical receiver including a dual gain path amplifier system |
| CN201181220Y (en) * | 2008-04-07 | 2009-01-14 | 中国科学院空间科学与应用研究中心 | Micro-current amplifier for spacing |
Non-Patent Citations (1)
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| 《中国优秀硕士学位论文全文数据库(电子期刊)工程科技Ⅱ辑》 20080531 王卫勋 微电流检测方法的研究 正文第4-8页 1-4 , * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106441504A (en) * | 2016-11-09 | 2017-02-22 | 珠江水利委员会珠江水利科学研究院 | Linear frequency modulation continuous wave radar water level telemeasuring device and method |
| CN107342743A (en) * | 2016-12-16 | 2017-11-10 | 山东金洲科瑞节能科技有限公司 | A kind of signal coarse adjustment amplification control circuit |
| CN113125846A (en) * | 2021-04-16 | 2021-07-16 | 成都理工大学 | Weak current measuring system |
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Application publication date: 20110406 |