A kind of high-precise synchronization vibrating data collection card of collection polymorphic type detection signal
Technical field
The present invention relates to a kind of data collecting cards, collect more used in equipment condition monitoring field especially with regard to one kind
The high-precise synchronization vibrating data collection card of type detection signal.
Background technique
Currently, domestic data acquisition technology has biggish development, but the type for acquiring signal still has certain limitation,
The precision of data acquisition is still to be improved, and application is restricted.External data acquisition technology research starting is more early, exploitation
Data collection system Technical comparing out is mature.The type of signal acquisition is more, range is wide, precision is high, good reliability, without periphery
Adjust circuit.But it is expensive, it is beyond affordability for some medium-sized and small enterprises, and the operation of system is comparatively laborious, and it is right
Operation and maintenance personnel are proposed higher requirement.Therefore, to the research of data collection system, to the branch of a variety of acquisition signals
The raising with acquisition precision is held, and does the design of interference performance and stability, there is great research significance.
Summary of the invention
In view of the above-mentioned problems, the object of the present invention is to provide a kind of high-precise synchronization vibration numbers of collection polymorphic type detection signal
According to capture card, high sensitivity, quality of output signals are good, reduce the number of data-out port.
To achieve the above object, the present invention takes following technical scheme: a kind of high-precision of collection polymorphic type detection signal is same
Walk vibrating data collection card, it is characterised in that: the capture card includes 3 road IEPE interface circuits, 1 road 4-20mA electric current input interface
Circuit, 1 tunnel ± 5V voltage signal input interface circuit, 1 tunnel millivolt level voltage input interface circuit, single-chip microcontroller and host computer;Often
The IEPE interface circuit all connects a constant-current source circuit all the way, and the IEPE interface circuit output end is through the constant-current source circuit
After be sequentially connected in series programmable amplifying circuit, filter circuit, single-ended transfer difference circuit and AD converter, the 4-20mA electric current is defeated
Incoming interface circuit output end is connect with the I/V conversion circuit input terminal;The I/V conversion circuit output end is sequentially connected in series
Programmable amplifying circuit, filter circuit, single-ended transfer difference circuit and AD converter;The millivolt level voltage input interface circuit output
End is sequentially connected in series programmable amplifying circuit, filter circuit, single-ended transfer difference circuit and AD converter;± 5V the voltage signal
Input interface circuit output end is sequentially connected in series filter circuit, single-ended transfer difference circuit and AD converter;± 5V the voltage
The AD converter in AD converter and the millivolt level voltage input interface circuit, 4-20mA electricity in signal input interface circuit
It is connected to after AD converter cascade in IEPE interface circuit described in AD converter and 3 tunnels in stream input interface circuit described
Single-chip microcontroller;In programmable amplifying circuit, 4-20mA electric current input interface circuit in the millivolt level voltage input interface circuit
The monolithic is connected to after programmable amplifying circuit control signal parallel connection in programmable amplifying circuit and 3 road IEPE interface circuits
Control is adjusted to the gain of each programmable amplifying circuit by the single-chip microcontroller in machine;The single-chip microcontroller by USB port with
The host computer is communicated.
Further, the constant-current source circuit includes constant current chip U1, five resistance R1~R5, capacitor C1, capacitor C2 and two
Pole pipe D1;The constant current chip U1 forward direction power end V+ connection+15V voltage constitutes power branch, and on the power branch simultaneously
It is grounded after joining the capacitor C1;The constant current chip U1 negative sense power end V- connection diode D1 anode, the constant current core
The fine tuning end ADJ of piece U1 is separately connected first branch one end and second branch one end, the first branch by the resistance R1 and
Resistance R2 is in series, and the second branch is in series by the resistance R3 and resistance R4;The first branch other end connects
It is connected to the diode D1 cathode, the second branch other end is connected to the diode D1 anode;The one end the resistance R5
It is connect with the IEPE interface circuit output end, the resistance R5 other end is connected with the one end the capacitor C2, the capacitor C2
Output end of the other end as the constant-current source circuit;And the diode D1 cathode is additionally coupled to the resistance R5 and the electricity
Hold between C2.
Further, the constant current chip uses the constant current chip of model LM334, and the diode D1 uses two pole of silicon
Pipe.
Further, the programmable amplifying circuit includes amplifier U2, resistance R8, resistance R11, capacitor C3 and capacitor C4;Institute
The input terminal for stating programmable amplifying circuit is connected to the amplifier U2 input terminal through the resistance R8, and the one end the resistance R11 connects
It is connected between the amplifier U2 input terminal and the resistance R8, the resistance R11 other end and the amplifier U2 ground terminal
It is grounded after GND is in parallel;The amplifier U2 negative sense power end V- connection -15V voltage constitutes power branch, and in the power branch
It is grounded after the upper parallel connection capacitor C3, the amplifier U2 forward direction power end V+ connection+15V voltage, and in positive power end V+
It is grounded after the capacitor C4 in parallel between+15V voltage;The output port OUT of the amplifier U2 is as the programming amplifying
The output end of circuit.
Further, the amplifier U2 uses the programmable gain amplifier of model PGA103.
Further, the filter circuit uses the active Butterworth lowpass wave circuit of two ranks, and uses model LF351
Amplifier.
Further, the single-ended transfer difference circuit includes operational amplifier U5, six resistance R22~resistance R27 and seven
A capacitor C11~C17;The operational amplifier U5 positive input is connect with the resistance R22 first end, the resistance R22
Second end is as the single-ended transfer difference circuit input end;The resistance R22 first end also respectively with the one end the resistance R23 and
The connection of the one end capacitor C13, the resistance R23 other end are connected to the resistance R24 first end, and the capacitor C13 other end connects
It is connected to the resistance R24 second end, and the resistance R24 second end is connected to the operational amplifier U5 negative sense output end, institute
Resistance R24 first end is stated as the single-ended transfer difference circuit negative sense output end;The end COMP of the operational amplifier U5 is through institute
State capacitor C14 ground connection;The operational amplifier U5 negative input be separately connected the one end the capacitor C15, the one end resistance R26 and
The one end resistance R27, the capacitor C15 other end are connected to the operational amplifier U5 forward direction output end, and the resistance R26 is another
End ground connection, the resistance R27 other end are connected to the resistance R25 first end, and the resistance R25 second end is connected to the fortune
Amplifier U5 forward direction output end is calculated, and the resistance R25 first end is as the single-ended transfer difference circuit forward direction output end;It is described
Operational amplifier U5 forward direction power end is connected to+15V voltage, which is also connected with by the capacitor C11 and capacitor C12
It is grounded after the filter circuit that parallel connection is constituted;The operational amplifier U5 negative sense power end is connected to -15V voltage, the negative sense power supply
End is grounded after being also connected with the filter circuit being made of the capacitor C16 and capacitor C17 parallel connection.
Further, the operational amplifier U5 uses the single-ended transfer difference chip of model OPA1632.
Further, the I/V conversion circuit carries out current/voltage-converted using the chip of model RCV420.
Further, the AD converter uses model ADS1271 analog-digital converter, and the single-chip microcontroller uses model
The chip of C8051F340.
The invention adopts the above technical scheme, which has the following advantages: 1, the present invention is able to achieve defeated to unlike signal
The data acquisition function of type sensor out solves the problems, such as that general capture card acquisition signal type is single, precision is not high.2,
IEPE sensor using piezo-electric crystal and built-in charge due to being amplified, with good excellent of high sensitivity, quality of output signals
Point.Therefore the present invention is provided with 3 road IEPE interface circuits as sensor acquisition channel.In addition, separately increasing 3 tunnel different types
The channel of signal input, respectively 4-20mA electric current is imported, ± 5V voltage signal is imported and millivolt level voltage input type is logical
Road.Each channel is all provided with signal conditioning circuit alone, reduces the interference of external environment, improves the accurate of acquisition data
Rate.3, the present invention uses the 24bit high-precision AD converter of model ADS1271, and 6 tunnel AD conversion are by daisy chain cascading one
It rises, sharing one has source crystal oscillator, and from finally, AD converter exports each channel data all the way, reduces the number of data-out port
Mesh, while meeting the requirement of high-precise synchronization acquisition.4, the present invention can in equipment state field using 6 road acquisition channels
To meet acquisition demand under normal circumstances, general, reliable data collection system a set of for subsequent development has important
Meaning.It is applied in equipment condition monitoring field in conclusion the present invention can extensively be sent out.
Detailed description of the invention
Fig. 1 is overall structure diagram of the invention;
Fig. 2 is constant-current source circuit structure schematic diagram of the invention;
Fig. 3 is programmable amplifying circuit structural schematic diagram of the invention;
Fig. 4 is filter circuit construction schematic diagrame of the invention;
Fig. 5 is single-ended transfer difference electrical block diagram of the invention;
Fig. 6 a is the single-ended sine wave analogous diagram of single-ended transfer difference circuit input of the invention;
Fig. 6 b is the differential sine wave analogous diagram of single-ended transfer difference circuit output of the invention;
Fig. 7 is I/V converting circuit structure schematic diagram of the invention;
Fig. 8 is AD converter electrical block diagram of the invention.
Specific embodiment
The present invention is described in detail below with reference to the accompanying drawings and embodiments.
As shown in Figure 1, the present invention provides a kind of high-precise synchronization vibrating data collection card of collection polymorphic type detection signal, needle
To the signal of different input types, respective signal conditioning module is pointedly devised.The present invention includes 3 road IEPE interface electricity
Road, 1 road 4-20mA electric current input interface circuit, 1 tunnel ± 5V voltage signal input interface circuit, 1 tunnel millivolt level voltage input connect
Mouth circuit, single-chip microcontroller and host computer (PC).3 road IEPE interface circuit follow-up signal conditioning circuit part-structures are identical, per all the way
IEPE interface circuit all connects a constant-current source circuit, is powered by constant-current source circuit to corresponding IEPE interface circuit, IEPE
Interface circuit output end is sequentially connected in series programmable amplifying circuit, filter circuit, single-ended transfer difference circuit after constant-current source circuit
And AD converter, it successively amplifies, filter and single-ended transfer difference processing, obtain carrying out modulus after the differential signal of standard turning
It changes.4-20mA electric current input interface circuit output end is connect with I/V conversion circuit input terminal, and 4-20mA current signal is converted to
It is exported after 0-5V voltage signal;I/V conversion circuit output end is sequentially connected in series programmable amplifying circuit, filter circuit, single-ended turn
Difference channel and AD converter.Millivolt level voltage input interface circuit output end is sequentially connected in series programmable amplifying circuit, filtering
Circuit, single-ended transfer difference circuit and AD converter.± 5V voltage signal input interface circuit output end is sequentially connected in series filtering
Circuit, single-ended transfer difference circuit and AD converter.AD converter and millivolt level electricity in ± 5V voltage signal input interface circuit
Press AD converter, the AD converter in 4-20mA electric current input interface circuit and the 3 road IEPE interfaces in input interface circuit
Single-chip microcontroller is connected to after AD converter cascade in circuit;Programmable amplifying circuit, 4- in millivolt level voltage input interface circuit
Programmable amplifying circuit control in programmable amplifying circuit and 3 road IEPE interface circuits in 20mA electric current input interface circuit is defeated
It is connected to single-chip microcontroller after entering end parallel connection, control is adjusted to the gain of each programmable amplifying circuit by single-chip microcontroller;Single-chip microcontroller passes through
USB port is communicated with host computer.
In a preferred embodiment, IEPE interface circuit connects two-wire system IEPE sensor, two-wire system IEPE sensing
The both threads of device are both signal wire and power supply line, and overall structure includes sensor and amplifying circuit.Therefore firstly the need of for
Sensor provides constant electric current, and the current value of general standard is 4mA, and driving voltage value is 24V.In order to improve anti-interference,
The present invention use with intersection flow amplification principle, as shown in Fig. 2, constant-current source circuit include constant current chip U1, five resistance R1~R5,
Capacitor C1, capacitor C2 and diode D1.Constant current chip U1 forward direction power end V+ connection+15V voltage constitutes power branch, and at this
It is grounded after shunt capacitance C1 on power branch;Constant current chip U1 negative sense power end V- connection diode D1 anode, constant current chip U1
Fine tuning end ADJ be separately connected first branch one end and second branch one end, the first branch is connected structure by resistance R1 and resistance R2
At second branch is in series by resistance R3 and resistance R4;The first branch other end is connected to diode D1 cathode, second branch
The other end is connected to diode D1 anode.The one end resistance R5 is connect with IEPE interface circuit output end, the resistance R5 other end and electricity
Hold the series connection of the one end C2, output end of the capacitor C2 other end as constant-current source circuit;And diode D1 cathode is additionally coupled to resistance
Between R5 and capacitor C2.
In above-described embodiment, constant current chip uses the constant current chip of model LM334, and diode D1 uses silicon diode;
Resistance value size by adjusting R2 and R4 can change the current output value of constant-current source, and wherein resistance R1 and R3 is used to carry out
Fine tuning.Simultaneously because constant current chip has positive temperature effect, therefore the negative of silicon diode can be utilized by increasing silicon diode
Temperature-responsive reduces influence of the exterior temperature change to circuit.Constant-current source circuit simple, high reliablity, function with circuit structure
Consume the advantages that low, distorted signals is small.
In a preferred embodiment, as shown in figure 3, programmable amplifying circuit includes amplifier U2, resistance R8, resistance
R11, capacitor C3 and capacitor C4.The input terminal of programmable amplifying circuit is connected to amplifier U2 input terminal, resistance R11 mono- through resistance R8
End is connected between amplifier U2 input terminal and resistance R8, and the resistance R11 other end is in parallel with amplifier U2 ground terminal GND to be followed by
Ground;Amplifier U2 negative sense power end V- connection -15V voltage constitutes power branch, and on the power branch after shunt capacitance C3
Ground connection, amplifier U2 forward direction power end V+ connection+15V voltage, and the shunt capacitance between positive power end V+ and+15V voltage
It is grounded after C4.Output end of the output port OUT of amplifier U2 as programmable amplifying circuit.
In above-described embodiment, amplifier U2 use model PGA103 programmable gain amplifier, can by two with
COM/TTL compatible input terminal is connected directly to one-chip machine port, controls gain size, gain can be set as to 1,
10 or 100, it can be widely applied to the wide field of the dynamic range of signals such as data collection system, general-purpose simulation plate and medical instrumentation
It closes.
In a preferred embodiment, since industry spot is generally there are a large amount of interference, it can be coupled by sensor
Into in circuit, these noises can make data that aliased distortion occur after collection.In order to avoid distortion, the present invention use
Filter circuit is set before AD conversion, interference noise can be effective filtered out.As shown in figure 4, filter circuit of the invention uses
The classical active Butterworth lowpass wave circuit of two ranks, and the model LF351 amplifier with high frequency band response is selected, it should
Filter circuit has many advantages, such as that circuit structure is simple, good wave filtering effect, and order fully meets practical application needs.Pass through change
The capacitance of capacitor C5 and C6 then can change the cutoff frequency of low-pass filter circuit, this hair in LF351 amplifier peripheral circuit
It is bright that the cutoff frequency of filter circuit is preferably set as 15KHz.
In a preferred embodiment, the present invention is in order to sufficiently excavate the performance of 24bit AD converter, in signal tune
Single-ended signal is converted to differential signal by the terminal of reason module.As shown in figure 5, single-ended transfer difference circuit includes operational amplifier
U5, six resistance R22~resistance R27 and seven capacitor C11~C17.Operational amplifier U5 positive input and resistance R22 the
One end connection, resistance R22 second end is as single-ended transfer difference circuit input end;Resistance R22 first end also respectively with resistance R23 mono-
End is connected with the one end capacitor C13, and the resistance R23 other end is connected to resistance R24 first end, and the capacitor C13 other end is connected to resistance
R24 second end, and resistance R24 second end is connected to operational amplifier U5 negative sense output end, resistance R24 first end is as single-ended turn
Difference channel negative sense output end.The end COMP of operational amplifier U5 is grounded through capacitor C14.Operational amplifier U5 negative input point
Not Lian Jie the one end capacitor C15, the one end resistance R26 and the one end resistance R27, the capacitor C15 other end is being connected to operational amplifier U5 just
To output end, resistance R26 other end ground connection, the resistance R27 other end is connected to resistance R25 first end, the connection of resistance R25 second end
To operational amplifier U5 forward direction output end, and resistance R25 first end is as single-ended transfer difference circuit forward direction output end.Operation amplifier
Device U5 forward direction power end is connected to+15V voltage, which is also connected with the filter being made of capacitor C11 and capacitor C12 parallel connection
It is grounded after wave circuit;Operational amplifier U5 negative sense power end is connected to -15V voltage, which is also connected with by capacitor C16
It is grounded after the filter circuit constituted with capacitor C17 parallel connection.
In above-described embodiment, operational amplifier U5 uses the single-ended transfer difference chip of model OPA1632, passes through
After Multisim analogue simulation (as shown in Fig. 6 a, Fig. 6 b), it can be seen that single-ended transfer difference circuit of the invention can effectively will be single
End signal is converted to differential signal.
In a preferred embodiment, I/V conversion circuit carries out current/voltage using the chip of model RCV420 and turns
It changes, as shown in Figure 7.
In a preferred embodiment, after each road sensor signal is converted to digital signal, most afterwards through AD converter
Carried out data transmission with single-chip microcontroller by spi bus.As shown in figure 8, AD converter uses model ADS1271 analog-to-digital conversion
The ADS1271 of device, each road can be cascaded up by DIN pin and DOUT pin, and sharing one has source crystal oscillator, reached to synchronize and be adopted
The requirement of collection.
In a preferred embodiment, single-chip microcontroller uses the chip of model C8051F340 comprising reset circuit,
Program download interface circuit and external RAM circuit etc., the chip self-carried USB interface can directly be communicated with host computer.
The various embodiments described above are merely to illustrate the present invention, and structure and size, setting position and the shape of each component are all can be with
It is varied, based on the technical solution of the present invention, the improvement and wait that all principles according to the present invention carry out individual part
With transformation, should not exclude except protection scope of the present invention.