CN102692883B - An analog input circuit for engineering-machinery-dedicated controller - Google Patents
An analog input circuit for engineering-machinery-dedicated controller Download PDFInfo
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- CN102692883B CN102692883B CN201210083818.5A CN201210083818A CN102692883B CN 102692883 B CN102692883 B CN 102692883B CN 201210083818 A CN201210083818 A CN 201210083818A CN 102692883 B CN102692883 B CN 102692883B
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Abstract
The invention discloses an analog input circuit for engineering-machinery-dedicated controller. The analog input circuit comprises a voltage-current transformation circuit, which is a current series negative feedback amplifier circuit, and an analog voltage input circuit, which includes orderly connected a first RC filter circuit having an input thereof connected with a current output of said voltage-current transformation circuit, a noninverting amplifying circuit, and an isolating circuit having an output thereof connected with an A/D sampling port of a control unit. The analog resistor input circuit of the invention has the characteristics of strong anti-interference capability, high reliability, good compatibility, flexible applicability, and convenient operation, is also adaptable to wretched field environment and applied to the control circuit of engineering machinery equipment.
Description
Technical field
The present invention relates to a kind of input circuit, relate in particular to a kind of simulated measurement input circuit of engineering machinery nonshared control unit.
Background technology
In China's construction machinery industry automatic field opertaing device, controller signals, except common analog quantity voltage input signal, current input signal, also has the imported analog input signal of resistance at present.And the ubiquitous problem of analog input (sampling) circuit: 1) comparatively simple to the Acquisition Circuit design of analog signals, lack isolation design, passage is difficult to meet the more needs in engineering machinery control system collection point less; 2) engineering machinery scene exists again signal to disturb greatly, can cause analog signals Acquisition Error large, and distorted signals impacts to control system entirety, can not meet the requirement of high-precision analog amount signals collecting; 3) in engineering mechanical device, some sensor signals are to exist with resistance input mode.
Less to the research of analog quantity resistance input circuit on engineering machinery opertaing device in the market, simulated measurement input circuit patent research mainly concentrates on Sampling Interface number of channels, sampling precision, and the aspect such as interference free performance.Simulated measurement input circuit is designed, aspect circuit sampling buffer circuit, mostly adopting light-coupled isolation mode, in the time carrying out Isolation input output channel with photoelectrical coupler, must all isolate all signals (comprising digital signal, control signal, status signal), make segregate both sides without any the contact on electrical equipment, otherwise this isolation is without any meaning.
Summary of the invention
For the problem of above-mentioned existence, the object of this invention is to provide a kind of simulated measurement input circuit of engineering machinery nonshared control unit, can effectively protect Acquisition Circuit, expand analog data collection scope, there is applying flexible, feature easy to use, with low cost.
The object of the invention is to be achieved through the following technical solutions:
A kind of simulated measurement input circuit of engineering machinery nonshared control unit, wherein, comprise a current/charge-voltage convertor and an analog quantity voltage input circuit, described current/charge-voltage convertor is a current-series negative-feedback amplifier circuit, described analog quantity voltage input circuit comprises the RC filtering circuit connecting successively, in-phase amplification circuit and buffer circuit, a described RC filtering circuit input connects the current output terminal of described current/charge-voltage convertor, and described buffer circuit exports the A/D sample port of control module to.
In another embodiment of the present invention, described current/charge-voltage convertor converts 0-5V d. c. voltage signal to the current signal of 0-10mA linearly.
In another embodiment of the present invention, described current/charge-voltage convertor comprises the first operational amplifier, between described the first operational amplifier and operating voltage V2401, be serially connected with the 2nd RC filtering circuit being formed by R2103 and C2102, ground connection after the anti-phase input terminating resistor R2403 of described the first operational amplifier, the normal phase input end of described the first operational amplifier meets Vin by resistance R 2401, between the normal phase input end of described the first operational amplifier and pull-up resistor R, be serially connected with resistance R 2402, series resistor R2404 between the inverting input of described the first operational amplifier and output terminal, the output terminal of described the first operational amplifier connects one end of pull-up resistor R by resistance R 2405, between described pull-up resistor R and the earth terminal of described resistance R 2403, be also serially connected with voltage stabilizing diode Z2101.
In another embodiment of the present invention, a described RC filtering circuit is made up of resistance R 2101 and capacitor C 2101.
In another embodiment of the present invention, described in-phase amplification circuit comprises the second operational amplifier, the inverting input of described the second operational amplifier is by resistance R 2408 ground connection, between the inverting input of described the second operational amplifier and output terminal, be serially connected with resistance R 2407, between described the second operational amplifier and operating voltage V2402, be serially connected with the 3rd RC filtering circuit being made up of resistance R 2104 and capacitor C 2103, the normal phase input end of described the second operational amplifier is by resistance R 2102 ground connection.
In another embodiment of the present invention, described buffer circuit comprises the 3rd operational amplifier, between the output terminal of the normal phase input end of described the 3rd operational amplifier and described the second operational amplifier, be serially connected with resistance R 2701, between described the 3rd operational amplifier and operating voltage V2403, be serially connected with the 4th RC filtering circuit being formed by resistance R 2105 and capacitor C 2101, the inverting input of described the 3rd operational amplifier is connected with the output terminal of described the 3rd operational amplifier by resistance R 2702, the output terminal of described the 3rd operational amplifier is also connected with the 5th RC filtering circuit being made up of resistance R 2703 and capacitor C 2104.
In another embodiment of the present invention, the variation range of described pull-up resistor R is 0-130 Ω.
Another technical scheme of the simulated measurement input circuit of a kind of engineering machinery nonshared control unit of the present invention is: comprise a resistance meausring bridge and a differential amplifier circuit, described resistance meausring bridge comprises resistance R 2401, resistance R 2402 and resistance R 2403, ground connection after described resistance R 2402 and described resistance R 2403 serial connections, ground connection after described resistance 2401 and pull-up resistor R serial connection, is connected in series a RC filtering circuit being made up of resistance R 2101 and capacitor C 2101 between described resistance meausring bridge and power supply V, described differential amplifier circuit comprises an operational amplifier, the normal phase input end of described operational amplifier is by resistance R 2103 ground connection, the inverting input of described operational amplifier is connected the output terminal of described operational amplifier by the 2nd RC filtering circuit being made up of with capacitor C 2104 resistance R 2405, between described operational amplifier and power supply V2401, be serially connected with by resistance R 2104 and capacitor C 2103 and form the 3rd RC filtering circuit, the normal phase input end of described operational amplifier is connected with described resistance meausring bridge by the 4th RC circuit being made up of with capacitor C 2102 resistance R 2102, the inverting input of described operational amplifier is connected with described resistance meausring bridge by resistance R 2404.
In another embodiment of the present invention, described resistance R 2102 resistance values equate with described resistance R 2404 resistance values, described resistance R 2103 resistance values equate with described resistance R 2405 resistance values, and described resistance R 2102 is far longer than described resistance R 2401 resistance values with the resistance value sum of described resistance R 2103.
Compared with the prior art, beneficial effect of the present invention is:
Analog quantity resistance input circuit in the present invention's design, input circuit input end adopts high resistant protected mode, and the filtering circuit of resistance capacitance formation, with the buffer circuit of certain input impedance, can effectively prevent that large undesired signal from pouring in, improve signals collecting anti-interference; Input circuit can change by adjusting the enlargement factor of in-phase amplification circuit the scope of sampling resistor, can also meet analog quantity resistance input range by the size of regulating constant current source circuit output current adjustable, measuring accuracy is 0.5% × full scale at 25 DEG C.
Brief description of the drawings
Fig. 1 is the circuit diagram of an embodiment of the simulated measurement input circuit of engineering machinery nonshared control unit of the present invention;
Fig. 2 is the circuit diagram of another embodiment of the simulated measurement input circuit of engineering machinery nonshared control unit of the present invention.
Embodiment
Below in conjunction with schematic diagram and concrete operations embodiment, the invention will be further described.
Simulated measurement input circuit of the present invention is to be TMS320F2812 based on DSP(model) part in the controller circuitry of Master control chip, whole controller circuitry also comprises other parts: switching value input, analog quantity D/A output circuit, power circuit, memory module and communication unit part composition.Based on the controller circuitry of DSP control module, 16 road analog input interfaces can be provided, enrich greatly interface resource.
Fig. 1 shows the circuit diagram of an embodiment of the simulated measurement input circuit of engineering machinery nonshared control unit of the present invention, as shown in the figure, this circuit comprises a current/charge-voltage convertor and an analog quantity voltage input circuit, current/charge-voltage convertor is a current-series negative-feedback amplifier circuit, analog quantity voltage input circuit comprises the RC filtering circuit connecting successively, in-phase amplification circuit and buffer circuit, the one RC filtering circuit input connects the current output terminal of current/charge-voltage convertor, and buffer circuit exports the A/D sample port of control module to.
Wherein, current/charge-voltage convertor comprises the first operational amplifier, between the first operational amplifier and operating voltage V2401, be serially connected with the 2nd RC filtering circuit being formed by R2103 and C2102, ground connection after the anti-phase input terminating resistor R2403 of the first operational amplifier, the normal phase input end of the first operational amplifier meets Vin by resistance R 2401, between the normal phase input end of the first operational amplifier and pull-up resistor R, be serially connected with resistance R 2402, series resistor R2404 between the inverting input of the first operational amplifier and output terminal, the output terminal of the first operational amplifier connects one end of pull-up resistor R by resistance R 2405, between the earth terminal of pull-up resistor R and resistance R 2403, be also serially connected with voltage stabilizing diode Z2101.Preferably, a RC filtering circuit is made up of resistance R 2101 and capacitor C 2101.
In-phase amplification circuit comprises the second operational amplifier, the inverting input of the second operational amplifier is by resistance R 2408 ground connection, between the inverting input of the second operational amplifier and output terminal, be serially connected with resistance R 2407, between the second operational amplifier and operating voltage V2402, be serially connected with the 3rd RC filtering circuit being made up of resistance R 2104 and capacitor C 2103, the normal phase input end of the second operational amplifier is by resistance R 2102 ground connection.
Buffer circuit comprises the 3rd operational amplifier, between the output terminal of the normal phase input end of the 3rd operational amplifier and the second operational amplifier, be serially connected with resistance R 2701, between the 3rd operational amplifier and operating voltage V2403, be serially connected with the 4th RC filtering circuit being formed by resistance R 2105 and capacitor C 2101, the inverting input of the 3rd operational amplifier is connected with the output terminal of the 3rd operational amplifier by resistance R 2702, and the output terminal of the 3rd operational amplifier is also connected with the 5th RC filtering circuit being made up of resistance R 2703 and capacitor C 2104.Wherein, the variation range of pull-up resistor R is 0-130 Ω.
This circuit prime is a voltage-current converting circuit, in amplifying circuit, introduce current-series negative feedback, can realize the conversion of voltage-to-current, the current signal that the d. c. voltage signal of 0-5V can be converted linearly to 0-10mA, the large I of output current is calculated by following formula: I=Vin/R2405.In practical application, needing has earth terminal by pull-up resistor R, from physical concept, has both introduced negative feedback in circuit, has introduced again positive feedback.In the time meeting R2404/R2403=R2402/R2401, the increase of the I that reduces to cause because of load R approximates reducing of the I that causes because of positive feedback effect, just in time offsets, because I becomes the controlled source of Vin, to complete the conversion of voltage-to-current.
By resistance type sensor signal access current output terminal, can obtain the magnitude of voltage on sensor.Circuit latter half is an analog quantity voltage input circuit, sensor resistance analog signals obtains the RC filtering circuit of voltage signal through R2101 and C2101 formation through constant-current source circuit effect, the signal collecting is processed, send into the in-phase amplification circuit that one end forms below, then the A/D sample port of control module sent into signal by the buffer circuit forming through one-level follower.
Based on DSP(herein the model of DSP be TMS320F2812) main control circuit Liao16 road A/D sampling channel is provided, can meet the input of 16 analog signalses simultaneously, greatly improved control interface quantity.If coordinate the controller system of two control chips, can obtain the analog acquisition passage on 32 tunnels.For engineering mechanical device provides a kind of high reliability and the hyperchannel demand of analog acquisition simultaneously, the analog signals acquisition process to the oil level in plant equipment, pressure, temperature and walking action control simultaneously, has improved the performance of control system.Due to of the present invention be all technical grade components and parts, adaptable range of stability is-30～70 DEG C, can comparatively under rugged environment, work, be applicable to long range measurements.Input circuit input end of the present invention adopts high resistant protected mode, and the filtering circuit of resistance capacitance formation, with the buffer circuit of certain input impedance, can effectively prevent that large undesired signal from pouring in, and has stronger interference free performance.In addition, high-precision analog amount input signal sampling of the present invention, measuring accuracy is 0.5% × full scale at 25 DEG C.
Change in example at one, as shown in Figure 2, simulated measurement input circuit of the present invention comprises a resistance meausring bridge and a differential amplifier circuit, resistance meausring bridge comprises resistance R 2401, resistance R 2402 and resistance R 2403, ground connection after resistance R 2402 and resistance R 2403 serial connections, ground connection after resistance 2401 and pull-up resistor R serial connection, is connected in series a RC filtering circuit being made up of resistance R 2101 and capacitor C 2101 between resistance meausring bridge and power supply V.Differential amplifier circuit comprises an operational amplifier, the normal phase input end of operational amplifier is by resistance R 2103 ground connection, the inverting input of operational amplifier is by the output terminal of the 2nd RC filtering circuit concatenation operation amplifier that is made up of resistance R 2405 and capacitor C 2104, between operational amplifier and power supply V2401, be serially connected with by resistance R 2104 and capacitor C 2103 and form the 3rd RC filtering circuit, the normal phase input end of operational amplifier is connected with resistance meausring bridge by the 4th RC circuit being made up of with capacitor C 2102 resistance R 2102, the inverting input of operational amplifier is connected with resistance meausring bridge by resistance R 2404.
In the present embodiment, for making differential amplifier input current balance, require R2102=R2404, R2103=R2405, and (R2102+R2103) >>R2401.Due to the operational amplifier single supply work in the present embodiment, in the variation range of resistance, the positive input of operational amplifier will be greater than anti-phase input forever, but the measuring bridge in the present embodiment can overcome the most of fluctuation of voltage signal source V, but can not thoroughly remove, be only suitable for short distance and measure.
Rig-site utilization shows, analog quantity resistance input circuit of the present invention has that antijamming capability is strong, reliability is high, compatible good, applying flexible, the feature such as easy to operate, can adapt to severe site environment, is applicable in the control circuit of engineering mechanical device.
Above specific embodiments of the invention be have been described in detail, but the present invention is not restricted to specific embodiment described above, it is just as example.To those skilled in the art, any equivalent modifications and alternative also all among category of the present invention.Therefore, equalization conversion and the amendment done without departing from the spirit and scope of the invention, all should contain within the scope of the invention.
Claims (8)
1. the simulated measurement input circuit of an engineering machinery nonshared control unit, it is characterized in that, comprise a current/charge-voltage convertor and an analog quantity voltage input circuit, described current/charge-voltage convertor is a current-series negative-feedback amplifier circuit, described analog quantity voltage input circuit comprises the RC filtering circuit connecting successively, in-phase amplification circuit and buffer circuit, a described RC filtering circuit input connects the current output terminal of described current/charge-voltage convertor, and described buffer circuit exports the A/D sample port of control module to; Described in-phase amplification circuit comprises the second operational amplifier, the inverting input of described the second operational amplifier is by resistance R 2408 ground connection, between the inverting input of described the second operational amplifier and output terminal, be serially connected with resistance R 2407, between described the second operational amplifier and operating voltage V2402, be serially connected with the 3rd RC filtering circuit being made up of resistance R 2104 and capacitor C 2103, the normal phase input end of described the second operational amplifier is by resistance R 2102 ground connection.
2. simulated measurement input circuit as claimed in claim 1, is characterized in that, described current/charge-voltage convertor converts 0-5V d. c. voltage signal to the current signal of 0-10mA linearly.
3. simulated measurement input circuit as claimed in claim 2, it is characterized in that, described current/charge-voltage convertor comprises the first operational amplifier, between described the first operational amplifier and operating voltage V2401, be serially connected with the 2nd RC filtering circuit being formed by R2103 and C2102, ground connection after the anti-phase input terminating resistor R2403 of described the first operational amplifier, the normal phase input end of described the first operational amplifier meets Vin by resistance R 2401, between the normal phase input end of described the first operational amplifier and pull-up resistor R, be serially connected with resistance R 2402, series resistor R2404 between the inverting input of described the first operational amplifier and output terminal, the output terminal of described the first operational amplifier connects one end of pull-up resistor R by resistance R 2405, between described pull-up resistor R and the earth terminal of described resistance R 2403, be also serially connected with voltage stabilizing diode Z2101.
4. simulated measurement input circuit as claimed in claim 1, is characterized in that, a described RC filtering circuit is made up of resistance R 2101 and capacitor C 2101.
5. simulated measurement input circuit as claimed in claim 1, it is characterized in that, described buffer circuit comprises the 3rd operational amplifier, between the output terminal of the normal phase input end of described the 3rd operational amplifier and described the second operational amplifier, be serially connected with resistance R 2701, between described the 3rd operational amplifier and operating voltage V2403, be serially connected with the 4th RC filtering circuit being formed by resistance R 2105 and capacitor C 2101, the inverting input of described the 3rd operational amplifier is connected with the output terminal of described the 3rd operational amplifier by resistance R 2702, the output terminal of described the 3rd operational amplifier is also connected with the 5th RC filtering circuit being made up of resistance R 2703 and capacitor C 2104.
6. simulated measurement input circuit as claimed in claim 3, is characterized in that, the variation range of described pull-up resistor R is 0-130 Ω.
7. the simulated measurement input circuit of an engineering machinery nonshared control unit, it is characterized in that, comprise a resistance meausring bridge and a differential amplifier circuit, described resistance meausring bridge comprises resistance R 2401, resistance R 2402 and resistance R 2403, ground connection after described resistance R 2402 and described resistance R 2403 serial connections, ground connection after described resistance 2401 and pull-up resistor R serial connection, is connected in series a RC filtering circuit being made up of resistance R 2101 and capacitor C 2101 between described resistance meausring bridge and power supply V, described differential amplifier circuit comprises an operational amplifier, the normal phase input end of described operational amplifier is by resistance R 2103 ground connection, the inverting input of described operational amplifier is connected the output terminal of described operational amplifier by the 2nd RC filtering circuit being made up of with capacitor C 2104 resistance R 2405, between described operational amplifier and power supply V2401, be serially connected with by resistance R 2104 and capacitor C 2103 and form the 3rd RC filtering circuit, the normal phase input end of described operational amplifier is connected with described resistance meausring bridge by the 4th RC circuit being made up of with capacitor C 2102 resistance R 2102, the inverting input of described operational amplifier is connected with described resistance meausring bridge by resistance R 2404.
8. the simulated measurement input circuit of engineering machinery nonshared control unit as claimed in claim 7, it is characterized in that, described resistance R 2102 resistance values equate with described resistance R 2404 resistance values, described resistance R 2103 resistance values equate with described resistance R 2405 resistance values, and described resistance R 2102 is far longer than described resistance R 2401 resistance values with the resistance value sum of described resistance R 2103.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201210083818.5A CN102692883B (en) | 2012-03-27 | 2012-03-27 | An analog input circuit for engineering-machinery-dedicated controller |
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| CN201210083818.5A CN102692883B (en) | 2012-03-27 | 2012-03-27 | An analog input circuit for engineering-machinery-dedicated controller |
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| CN102692883A CN102692883A (en) | 2012-09-26 |
| CN102692883B true CN102692883B (en) | 2014-08-06 |
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| CN104052417A (en) * | 2013-03-11 | 2014-09-17 | 成都艺创科技有限公司 | Magnetic head amplification circuit used for router |
| CN103702102B (en) * | 2013-12-31 | 2016-03-16 | 青岛歌尔声学科技有限公司 | A kind of jamproof signal processing circuit and a kind of anti-interference 3D glasses |
| CN104536416B (en) * | 2014-12-25 | 2017-05-10 | 重庆川仪自动化股份有限公司 | Analog quantity input acquisition circuit for restraining electromagnetic interference in industrial control system |
| CN105444921A (en) * | 2015-11-04 | 2016-03-30 | 中国北方发动机研究所(天津) | Signal imitation circuit and method for thermocouple sensor |
| CN106603078B (en) * | 2016-12-21 | 2020-11-27 | 中国航空工业集团公司雷华电子技术研究所 | Circuit for improving ADC sampling precision |
| CN106533422A (en) * | 2017-01-04 | 2017-03-22 | 四川埃姆克伺服科技有限公司 | Analog quantity conditioning circuit |
| CN106788392B (en) * | 2017-01-09 | 2023-05-09 | 四川埃姆克伺服科技有限公司 | Single-ended analog input interface circuit for servo controller |
| CN106989793B (en) * | 2017-04-28 | 2020-02-14 | 中航工业南航（深圳）测控技术有限公司 | Sampling circuit and detection device |
| CN107425845B (en) * | 2017-05-08 | 2020-12-25 | 华为技术有限公司 | Superposition operation circuit and floating voltage digital-to-analog conversion circuit |
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| US6608583B1 (en) * | 2002-04-30 | 2003-08-19 | Oki Electric Industry Co., Ltd. | Analog signal input circuit in analog signal processing apparatus |
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