CN104635555A - Analog signal conditioning circuit of high-accuracy data collecting system - Google Patents
Analog signal conditioning circuit of high-accuracy data collecting system Download PDFInfo
- Publication number
- CN104635555A CN104635555A CN201310554996.6A CN201310554996A CN104635555A CN 104635555 A CN104635555 A CN 104635555A CN 201310554996 A CN201310554996 A CN 201310554996A CN 104635555 A CN104635555 A CN 104635555A
- Authority
- CN
- China
- Prior art keywords
- analog signal
- circuit
- pass filter
- signal conditioning
- converter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Amplifiers (AREA)
Abstract
Disclosed is an analog signal conditioning circuit of a high-accuracy data collecting system. A preposed differential amplifier INA128, a fourth-order Butterworth active low-pass filter, a main amplifier and a 50Hz wave trap circuit are sequentially connected and then input to a DSP (digital signal processor) through an A/D converter, the fourth-order Butterworth active low-pass filter is composed by cascading two second-order wireless gain multi-end feedback low-pass filters, the main amplifier is formed by combining high-common-mode-rejection-ratio double-end-input single-end-output type instrument program control amplifiers PGA204 and PGA205, the wave trap circuit is a second-order double-T-type 50Hz wave trap circuit, and the A/D converter is LTC2400. The analog signal conditioning circuit has the advantages of high accuracy, low noise and high interference resistance, is suitable for serving as front-end analog signal conditioning circuit of a signal collecting system for field work, has quite high common mode rejection ratio and series mode rejection ratio and is especially suitable for being used in a data collecting module of a geophysical exploration instrument.
Description
Technical field
The present invention relates to a kind of data acquisition circuit, especially High Precise Data Acquisition System analog signal conditioner circuit.
Background technology
Automatic measurement and control system all be unable to do without data acquisition and procession, and it is the source of these system original dates.Data acquisition technology is an important branch of information science, is widely used in the hyundai electronics information real time processing engineerings such as signal transacting, spectrum analysis, communication and image procossing.Good data acquisition system (DAS) ensures that intelligent instrument normally runs, the key factor of the raw data of correct identification sensor signal, acquisition algorithm software.What data acquisition technology contained has a wide range of knowlege, comprise analog/digital conversion technology, analog signal conditioner, microprocessor technology, CPLD/FPAG technology, DSP technology, data communication and connect 13 technology, digital signal processing, anti-interference with multinomial technology such as electromagnetic Compatibility Design, and for different applied environments and occasion, different instruments or sensor have different requirements to the collection of data again, therefore, data acquisition also becomes the gordian technique that difficult point in Design of Intelligence Instruments is many, workload large, need cost high.General data acquisition system (DAS) is divided into analog signal conditioner part and signal process part, and wherein simulation part completes that multichannel signal synchronously amplifies, gathers, the function of anti-aliasing filter, notch filter.Therefore analog signal conditioner circuit has vital role in data acquisition system (DAS), it wants according to the requirement of instrument, simulating signal to be converted into digital signal, the height as sample frequency, the rejection ability to neighbourhood noise, needs the problem considered when self being all Analogue signal conditioning circuit to the interference of useful signal and sampling precision etc.Particularly, interference faint to signal amplitude and noise amplitude is large, accuracy requirement is high, dynamic range is large, the requirement of real-time of data is high situation, have higher requirement to the design of analog signal conditioner circuit.
Summary of the invention
The technical matters that the application will solve overcomes above-mentioned defect, provides a kind of High Precise Data Acquisition System analog signal conditioner circuit.
For solving the problems of the technologies described above, the technical scheme of employing is:
High Precise Data Acquisition System analog signal conditioner circuit, difference preamplifier INAl28, quadravalence Butterworth active low-pass filter, main amplifier, 50Hz notch filter circuit input to DSP through A/D converter after being linked in sequence; This quadravalence Butterworth active low-pass filter is that two-stage second order wireless gain multiterminal feedback low-pass filter cascaded series becomes, main amplifier is by the double-width grinding Single-end output type instrument programmable amplifier PGA204 of high cmrr, PGA205 combines, notch filter circuit is a double-T shaped 50Hz notch filter circuit of second order, and A/D converter is LTC2400.
The invention has the beneficial effects as follows: analog signal conditioner circuit has the characteristics such as high precision, low noise, antijamming capability be strong, accommodate the signal acquiring system front end analogue signal conditioning circuit as field work, there is very high common-mode rejection ratio and series mode rejection ratio, to the 50hz Hz noise be extensively present in physical environment, there is very strong inhibition, A/D for simulating signal changes figure place and reaches 24, the detection that the microvolt level of signal is changed can be realized, be specially adapted in the data acquisition module of geophysical instrument.
Accompanying drawing explanation
Fig. 1 is analog signal conditioner electrical block diagram;
Fig. 2 is two-stage programmable amplifier cascade schematic diagram.
Embodiment
High Precise Data Acquisition System analog signal conditioner circuit, difference preamplifier INAl28, quadravalence Butterworth active low-pass filter, main amplifier, 50Hz notch filter circuit input to DSP through A/D converter after being linked in sequence; This quadravalence Butterworth active low-pass filter is that two-stage second order wireless gain multiterminal feedback low-pass filter cascaded series becomes, main amplifier is by the double-width grinding Single-end output type instrument programmable amplifier PGA204 of high cmrr, PGA205 combines, notch filter circuit is a double-T shaped 50Hz notch filter circuit of second order, and A/D converter is LTC2400.
The noise figure of prime amplifier has decisive role for the noisiness of whole detection system, the detectable minimum signal of system depends on the noise figure of low noise amplifier, because the noise that it produces can be amplified further by follow-up amplifiers at different levels.At present, low noise amplifier can design by selecting the good integrated circuit of noise objective.INAl28 is a kind of low-power consumption, high-precision meter differential amplifier; it has lower input offset voltage and temperature coefficient to compare common integrated operational amplifier; very favourable to the input realizing microvolt level; simultaneously its input end inside is integrated with the ± overvoltage protection of 40 volts; differential input end exceedes ± and the voltage of 40 volts protects automatically; make device exempt from damage, good suppression is served to the common mode interference of input signal.Consider the easy implementation on signal characteristic and hardware, system have employed Butterworth active low-pass filter on low-pass filter.Consider the interference to signal detecting feeble signal and need also will reduce as much as possible system self while suppressing neighbourhood noise in the background of very noisy, and the minor fluctuations in passband also likely produces large interference to faint signal intensity, so select quadravalence Butterworth filter here.This wave filter feeds back low-pass filter cascaded series by two-stage second order Infinite gain multiterminal and becomes fourth order low-pass wave filter.When the dynamic range of Received signal strength is larger, in order to improve the signal to noise ratio (S/N ratio) of instrument, measuring accuracy and input dynamic range, leading portion simulating signal be have employed to the method for two-stage instrument programmable amplifier cascade, and two-stage programming amplifying adopts the mode of the differential connection of direct-coupling, the common mode interference that every grade is introduced is reduced to minimum.Amplifier section main task is under the control of the dsp, elementary amplifying signal is amplified to ADE and quantizes between optimal zone, to improve dynamic range and the sensitivity of instrument.Have finally chosen PGA204, PGA205 combination.PGA204, PGA205 are the instrument programmable amplifiers of the high cmrr that BB company releases, and common mode inhibition reaches as high as 123DB.Prime amplifier adopts the mode of voltage follower.The controlled enlargement factor of PGA204 is 1,10,100,1000; The controlled enlargement factor of PGA205 is 1,2,4,8.So the controlled enlargement factor of programming amplifying part can have 16 kinds of array modes after cascade, 2,4,8,16,20,40,80,160,200,400,800,1600,2000,4000,8000,16000, can system requirements be met.PGA204, PGA205 are double-width grinding Single-end output type instrument programmable amplifier.It is still unipolar signal that two positive and negative electrodes receive signal through prime amplifier, makes it respectively as the positive-negative input end of wherein a slice PGA205, constitutes first order differential amplifier.Two panels PGA205 exports, and respectively as the positive-negative input end of PGA204, constitutes second level differential amplifier.Whole process have employed signals reverse difference and effectively inhibits common mode interference, improves amplifier signal to noise ratio (S/N ratio).Two-stage programmable amplifier cascade schematic diagram as shown in Figure 2.When interference voltage exceed signal voltage a lot of time, it will arrange the gain of prime amplifier and main amplifier, makes amplifier can not effectively amplify the Received signal strength carrying out sensor, therefore must arrange 50Hz trapper in Acquisition Circuit.In order to reach the ability detecting level signal, adopting the LTC2400 of Linear Tech here, is 24 minimum in the world pin-point accuracy A/D converters.Inside has the higher integrated oscillator clock of precision, and outside does not need any frequency adjustment element.This converter has the linearity of 4ppm, and 24 without leaking code; Superior direct-current performance and the good low-noise characteristics such as the full scale gain error of 4ppm.In addition, this converter has SPI digital interface, easily with Microprocessor Interface, simplifies line design.LTC2400 is single pass A/D converter, and its packing forms is that S08 is SMD.
Claims (1)
1. High Precise Data Acquisition System analog signal conditioner circuit, is characterized in that: difference preamplifier INAl28, quadravalence Butterworth active low-pass filter, main amplifier, 50Hz notch filter circuit input to DSP through A/D converter after being linked in sequence; This quadravalence Butterworth active low-pass filter is that two-stage second order wireless gain multiterminal feedback low-pass filter cascaded series becomes, main amplifier is by the double-width grinding Single-end output type instrument programmable amplifier PGA204 of high cmrr, PGA205 combines, notch filter circuit is a double-T shaped 50Hz notch filter circuit of second order, and A/D converter is LTC2400.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310554996.6A CN104635555A (en) | 2013-11-08 | 2013-11-08 | Analog signal conditioning circuit of high-accuracy data collecting system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310554996.6A CN104635555A (en) | 2013-11-08 | 2013-11-08 | Analog signal conditioning circuit of high-accuracy data collecting system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104635555A true CN104635555A (en) | 2015-05-20 |
Family
ID=53214434
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310554996.6A Pending CN104635555A (en) | 2013-11-08 | 2013-11-08 | Analog signal conditioning circuit of high-accuracy data collecting system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104635555A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106291120A (en) * | 2015-05-25 | 2017-01-04 | 国家电网公司 | A kind of capacitive apparatus medium loss measuring device with electricity |
| CN106452446A (en) * | 2016-10-21 | 2017-02-22 | 桂林电子科技大学 | Signal conditioning method and circuit based on linear phase front-end high-speed data collection |
| CN106707895A (en) * | 2017-02-24 | 2017-05-24 | 中国石油大学(北京) | High-precision synchronous vibration data collection card for various types of detection signals |
| CN109425366A (en) * | 2017-09-04 | 2019-03-05 | 南京理工大学 | A kind of analog signal processing circuit for active optics micro-displacement sensor |
| CN111323828A (en) * | 2020-04-02 | 2020-06-23 | 中国海洋大学 | Program-controlled gain type ocean electric field signal acquisition method, system, device and application |
| WO2022160953A1 (en) * | 2021-01-29 | 2022-08-04 | 清华大学深圳国际研究生院 | Weak current amplifier circuit and sensor system |
-
2013
- 2013-11-08 CN CN201310554996.6A patent/CN104635555A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106291120A (en) * | 2015-05-25 | 2017-01-04 | 国家电网公司 | A kind of capacitive apparatus medium loss measuring device with electricity |
| CN106452446A (en) * | 2016-10-21 | 2017-02-22 | 桂林电子科技大学 | Signal conditioning method and circuit based on linear phase front-end high-speed data collection |
| CN106707895A (en) * | 2017-02-24 | 2017-05-24 | 中国石油大学(北京) | High-precision synchronous vibration data collection card for various types of detection signals |
| CN106707895B (en) * | 2017-02-24 | 2019-02-12 | 中国石油大学(北京) | A kind of high-precise synchronization vibrating data collection card of collection polymorphic type detection signal |
| CN109425366A (en) * | 2017-09-04 | 2019-03-05 | 南京理工大学 | A kind of analog signal processing circuit for active optics micro-displacement sensor |
| CN111323828A (en) * | 2020-04-02 | 2020-06-23 | 中国海洋大学 | Program-controlled gain type ocean electric field signal acquisition method, system, device and application |
| WO2022160953A1 (en) * | 2021-01-29 | 2022-08-04 | 清华大学深圳国际研究生院 | Weak current amplifier circuit and sensor system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104635555A (en) | Analog signal conditioning circuit of high-accuracy data collecting system | |
| CN101964633B (en) | Lock-in amplifier circuit for detecting terahertz pulse signals | |
| CN105676263B (en) | A kind of pulse signal peak-value detection method based on phase compensation | |
| CN107124179B (en) | Phase-locked amplifier for detecting weak photocurrent signal | |
| CN206756755U (en) | A kind of stress wave signal conditioning device | |
| CN104320092B (en) | A kind of broadband low noise differential amplifier circuit of Weak absorption | |
| CN113532492A (en) | Static phase-locked amplifying circuit of fiber Bragg grating displacement output signal | |
| CN109974799B (en) | Self-adaptive electromagnetic flowmeter polarization noise cancellation system based on feedforward control | |
| CN109342805B (en) | High-precision microampere current detection circuit | |
| CN204244188U (en) | Signal based on lock-in amplifier amplifies and testing circuit | |
| CN203416227U (en) | Small signal amplification circuit | |
| CN201830211U (en) | Lock-in amplifying circuit adopting CD552-R3 chip | |
| CN104485914A (en) | Detection and processing circuit for biological weak signal | |
| CN204272046U (en) | A kind of biological Detection of Weak Signals and treatment circuit | |
| CN113866497A (en) | Collection system based on electric power marketing data | |
| CN111751611B (en) | Weak current measurement system | |
| CN115792375A (en) | FPGA-based Fourier series detection device for weak periodic signals under strong noise background | |
| CN106292391A (en) | Multichannel data acquisition system | |
| CN114624313A (en) | Corrosion monitoring system | |
| CN211978642U (en) | Armored vehicle lubricating oil abrasive particle on-line monitoring device | |
| CN104706344A (en) | Electrocardiosignal measurement collecting system | |
| CN112630524A (en) | Low-current signal acquisition processing circuit and acquisition processing method | |
| CN209673219U (en) | A kind of audio signal analysis device based on FFT | |
| CN206135885U (en) | Based on high -speed data acquisition signal conditioning circuit of linear phase front end | |
| CN217738500U (en) | Conditioning circuit of piezoresistive pressure sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20150520 |
|
| WD01 | Invention patent application deemed withdrawn after publication |