CN208283224U - A kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit - Google Patents
A kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit Download PDFInfo
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- CN208283224U CN208283224U CN201820997332.5U CN201820997332U CN208283224U CN 208283224 U CN208283224 U CN 208283224U CN 201820997332 U CN201820997332 U CN 201820997332U CN 208283224 U CN208283224 U CN 208283224U
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Abstract
The utility model relates to a kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuits, it include silicon photo diode, the weak current pulse signal amplification that silicon photo diode exports can be converted into the current/voltage-converted unit of burning voltage pulse signal " SIG ", voltage pulse signal " SIG " can be cut into the dual-channel type analog switching circuit of voltage pulse signal " NR68 " identical with pulse control signal M1 and M2 duty ratio and " NR66 " output, voltage pulse signal " NR68 " and " NR66 " can be synthesized ABS pulse signal through subtracter, it is low-pass filtered again to be converted into for the acquisition of A/D acquisition unit, send the operational amplifier circuit that microcontroller carries out the stable level signal of real-time intensity control to, circuit structure is scientific and reasonable, anti- electrical Interference ability is strong, work can It leans on and stablizes, accurate detection data can be provided for sample gas pond, robust techniques are provided and are guaranteed for preceding scattering dust measurement instrument raising dust detection accuracy and work confidence level, meet preceding scattering dust measurement instrument sample gas pond matches requirement, there is very strong practicability.
Description
Technical field
The utility model relates to photoelectric detection technology field, especially a kind of preceding scattering dust measurement instrument sample gas pond Photoelectric Detection
Circuit.
Background technique
Preceding scattering dust measurement instrument sample gas pond is that one kind is based on different dusts particle with different spectral absorption and reflection characteristic machine
The environmentally friendly flue gas detection device for managing setting, is widely used at present in environmentally friendly dust detection system.Its main feature is that being with laser
Incident light source manages intracorporal sample gas as test object in gas pond to charge, is to test and analyze instrument with spectrometer.When work, according to
The difference between incident intensity and output intensity detected according to spectrometer is as the light caused in sample gas pond by dust in flue gas
Thus contained dust concentration and attribute in detected sample gas are calculated and determined to strong waste.It can be seen that the incident light of light source
It is by force the benchmark tested and analyzed, so the light stability of light source is most important, and incident intensity and outgoing involved in it
The performance of the detection circuit of light intensity and detection accuracy, the reliability of detection data are closely related, therefore also most important.At present preceding
The basic structure of photoelectric detective circuit used in scattering dust measurement instrument sample gas pond is as shown in Figure 1, include silicon photo diode 1, fortune
Discharge road 2 and A/D acquisition unit 3, in which: the silicon photo diode 1 has acquisition optical signal and converts optical signals into electricity
The function of signal, have response is fast, high sensitivity, good linearity and noise are low, receive illumination after can export with it is opposite by force by irradiation
The features such as current signal answered, when work, by the current signal of silicon photo diode output after operational amplifier circuit 2 carries out level-one amplification
Output voltage signal, then the corresponding digital voltage signal for detecting light intensity, dust detector root are represented through the output of A/D acquisition unit 3
The difference of the incident intensity and output intensity that provide according to photoelectric detective circuit detection determines dust particles contained by flue gas in sample gas pond
Concentration and attribute.Its a fly in the ointment is, since the optical signal that silicon photo diode detects is generally fainter, therefore in reality
External arranging photoamplifier circuit is needed in operation, however the type selecting and circuit layout due to circuit components can detonator circuit parameters
Variation, therefore will lead to generation interference noise, thus certain interference effect can be brought to output electric signal, make photoelectric detective circuit
Linear response degree be deteriorated, also reduce signal-to-noise ratio, so as to cause influence light-intensity test data accuracy and reliability, finally
Influence functional reliability, the confidence level of detection data of dust detector.So the photoelectric detective circuit of structure type is total at present
Scientific and reasonable, anti-electrical Interference ability is owed there are structure on body and job stability is poor, is difficult to meet preceding scattering dust measurement instrument
Actual operation requirements.
Summary of the invention
The purpose of this utility model is the photoelectric detective circuit that overcome institute's adapted in existing preceding scattering dust measurement instrument sample gas pond
It is relatively rationally and science, anti-electrical to provide a kind of structure for anti-electrical Interference ability and the poor deficiency of job stability
Interference performance is strong, is conducive to improve the preceding scattering dust measurement instrument sample gas pond of circuit functional reliability and the detection data accuracy of sample gas pond
Use photoelectric detective circuit.
The preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit of the utility model, main body include silicon photo diode, fortune
Discharge road and A/D acquisition unit, it is characterised in that: also includes current/voltage-converted unit and simulation in photoelectric detective circuit
Switching circuit, in which:
The current/voltage-converted unit main body is one equipped with signal input pin+IN in the same direction, reverse signal input
The amplifier integration module U1 of foot-IN, signal output pin OUT and working power input pin V+ and V-, the working power input
It is provided with the filter circuit being made of magnetic bead B1 and capacitor C3 and C4 on foot V+, is arranged on the working power input pin V-
Have a filter circuit being made of magnetic bead B2 and capacitor C5 and C6, the signal input pin+IN in the same direction ground connection, and with silicon light two
The anode of pole pipe D1 is connected, and the reverse signal input pin-IN is connected with the cathode of silicon photo diode D1, and with by resistance R1
A connects end altogether for constituting integrating circuit with capacitor C1 parallel connection is connected, another connects end altogether of integrating circuit is removed to be exported with signal
It outside foot OUT is connected, is also grounded by concatenated blocking filter condenser C2 and pull down resistor R2, and in filter condenser C2 under
The output contact of voltage signal " SIG " is provided on the interface point of pull-up resistor R2；When work, silicon photo diode D1 is connected across amplifier
On signal input pin+IN and reverse signal the input pin-IN in the same direction of integration module U1, signal input pin+IN ground connection in the same direction, according to
" void is disconnected " characteristic of amplifier input terminal, meets the requirement that silicon photo diode output loading is zero, meanwhile, integrating circuit is arranged anti-
To between signal input pin-IN and signal output pin OUT, the weak current pulse signal exported by silicon photo diode D1 is by product
Point and level-one amplifier be converted into amplification voltage pulse signal, then through filter condenser C2 blocking, filter out the direct current being wherein mingled with
Obtained after interference signal with by irradiation corresponding and stable voltage pulse signal " SIG " by force；
The analog switching circuit main body is a dual analog being made of analog switch modules A and analog switch module B
Switch integrated chip U2, in which: 2.5V working power input pin VCC, voltage pulse are provided in the analog switch modules A
The arteries and veins that signal " SIG " accesses foot NOA, NR68 signal output pin COMA, signal input grounding foot NCA and provided by microcontroller
The access of punching control signal M1 controls foot INA；Power ground foot GND is provided in the analog switch module 2, by microcontroller
The access control foot INB for the pulse control signal M2 that device provides, voltage pulse signal " SIG " access foot NCB, NR66 signal output
Foot COMB and signal input grounding foot NOB, is provided on the working power input pin VCC by magnetic bead B3 and capacitor
The filter circuit that C7, C8 are constituted；When work, the pulse control signal M1 and M2 provided by microcontroller is respectively through INA foot and INB
Foot input, voltage pulse signal " SIG " is inputted through NOA foot and NCB foot respectively, by pulse control signal M1 and M2 control switch
Movement, wherein the pulse control signal M1 and M2 is identical as the light source drive signal period in light control system, phase phase difference
Certain angle, with certain duty ratio, input can be cut into voltage pulse signal " SIG " after passing through analog switching circuit and arteries and veins
The identical voltage pulse signal " NR68 " of punching control signal M1 and M2 duty ratio and " NR66 " output；
The operational amplifier circuit main body is the integration module U3 that one includes amplifier comparison module A and operational amplifier filter B,
Signal input pin+INA and reverse signal input pin-INA in the same direction, power supply wiring foot are provided on the amplifier comparison module A
It is defeated that signal input pin+INB and reverse signal in the same direction are provided on V- and signal output pin OUTA, the operational amplifier filter B
Enter foot-INB, power supply wiring foot V+ and signal output pin OUTB, in which: in amplifier comparison module A, the signal in the same direction is defeated
Enter one end and NR4 feedback signal acquisition contact that foot+INA above while is altogether connected to resistance R3 and resistance R4, the other end of resistance R3
On be provided with the electric terminal of NR68, the other end ground connection of resistance R4；Reverse signal input pin-the INA is upper while connecing altogether
There are one end of resistance R5 and resistance R6, input electric terminal NR66, the other end of resistance R6 are provided on the other end of resistance R5
It is connected with the signal output pin OUTA for being equipped with ABS output signal contact, thus constituting an operation result is ABS output signal
Subtraction circuit, in addition, being provided with the filtering being made of magnetic bead B3 and capacitor C9 and C10 on the power supply wiring foot V-
Circuit；In operational amplifier filter B, the signal input pin+INB in the same direction is grounded by capacitor C11, while passing through resistance
One end of R7 and capacitor C12 and one end of resistance R8 mutually connect altogether, the other end and the ABS in amplifier comparison module A of resistance R8
Output signal contact is connected, the other end of capacitor C12 simultaneously with the signal output pin OUTB and electricity that are equipped with output contact AD4
One end of resistance R9 connects connected altogether, and the other end of resistance R9 connects with one end of reverse signal input pin-INB and resistance R10 altogether simultaneously
It is connected, thus the other end ground connection of resistance R10 constitutes a low-pass filter circuit, furthermore on the power supply wiring foot V+
It is provided with the filter circuit being made of resistance B5 and capacitor C14 and C15；When work, subtraction circuit will be by analog switch electricity
Road cuts two pulse voltage signals " NR68 " identical with pulse control signal M1 and M2 duty ratio provided and " NR66 " is closed
At output ABS pulse signal, finally pulse signal is converted into being exported by output contact AD4 by low-pass filter circuit, be convenient for
The acquisition of A/D acquisition unit sends the stable level signal that microcontroller carries out real-time intensity control to.
Scattering dust measurement instrument sample gas pond photoelectric detective circuit before the utility model based on above-mentioned design, due in traditional light
Increase on the basis of power detection circuit and is provided with current/voltage converter circuit, dual-channel analog switching circuit and by operational amplifier circuit
Change the comprehensive electricity being set to be made of amplifier comparison module A and operational amplifier filter B, with subtracter and functions of low-pass filter
Silicon photo diode can be acquired the weak current pulse signal amplification provided and be converted into stable voltage pulse signal " SIG " by road,
And provided by microcontroller, phase phase difference certain angle identical as the light source drive signal period in light control system, have one
Voltage pulse signal " SIG " is cut into and pulse control signal M1 and M2 duty by the pulse control signal M1 and M2 for determining duty ratio
Output ABS pulse signal is synthesized than identical voltage pulse signal " NR68 " and " NR66 ", then through subtracter, finally carries out low pass
It filters, the ABS pulse signal for synthesizing output is converted into acquiring for A/D acquisition unit, sends microcontroller progress in real time
The stable level signal of intensity control.So the photoelectric detective circuit of the utility model effectively overcomes existing Photoelectric Detection electricity
The poor deficiency of anti-electrical Interference ability and job stability present in road, the utility model obviously have circuit structure section
It learns and reasonable, anti-electrical Interference ability is strong, reliable operation and stabilization, can provide accurate detection data for sample gas pond, be preceding scattered
It penetrates dust gauge and dust detection accuracy and work confidence level offer robust techniques guarantee, scattering dust measurement instrument sample gas pond before meeting is provided
Requirement is matched, there is very strong practicability and valuable market application prospect.
Detailed description of the invention
Fig. 1 is existing photoelectric detective circuit structural block diagram relevant to the utility model；
Fig. 2 is the circuit structure block diagram of the utility model embodiment；
Fig. 3 is the electrical structure schematic diagram of current/voltage-converted unit in the utility model embodiment；
Fig. 4 is the electrical structure schematic diagram of analog switching circuit in the utility model embodiment；
Fig. 5 is the electrical structure schematic diagram of operational amplifier circuit in the utility model embodiment.
In figure:
1. 2. operational amplifier circuit 3.A/D acquisition unit of silicon photo diode, 4. current/voltage-converted unit
5. analog switching circuit.
Specific embodiment
With reference to the accompanying drawing and exemplary embodiments the utility model is described in further detail.
In Fig. 1, the preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit of the utility model, main body includes silicon light two
Pole pipe 1, operational amplifier circuit 2 and A/D acquisition unit 3, it is characterised in that: also include current/voltage-converted in photoelectric detective circuit
Unit 4 and analog switching circuit 5, in which:
4 main body of current/voltage-converted unit is one equipped with signal input pin+IN in the same direction, reverse signal input
The amplifier integration module U1 of foot-IN, signal output pin OUT and working power input pin V+ and V-, the working power input
It is provided with the filter circuit being made of magnetic bead B1 and capacitor C3 and C4 on foot V+, is arranged on the working power input pin V-
Have a filter circuit being made of magnetic bead B2 and capacitor C5 and C6, the signal input pin+IN in the same direction ground connection, and with silicon light two
The anode of pole pipe D1 is connected, and the reverse signal input pin-IN is connected with the cathode of silicon photo diode D1, and with by resistance R1
A connects end altogether for constituting integrating circuit with capacitor C1 parallel connection is connected, another connects end altogether of integrating circuit is removed to be exported with signal
It outside foot OUT is connected, is also grounded by concatenated blocking filter condenser C2 and pull down resistor R2, and in filter condenser C2 under
The output contact of voltage signal " SIG " is provided on the interface point of pull-up resistor R2；When work, silicon photo diode D1 is connected across amplifier
On signal input pin+IN and reverse signal the input pin-IN in the same direction of integration module U1, signal input pin+IN ground connection in the same direction, according to
" void is disconnected " characteristic of amplifier input terminal, meets the requirement that silicon photo diode output loading is zero, meanwhile, integrating circuit is arranged anti-
To between signal input pin-IN and signal output pin OUT, the weak current pulse signal exported by silicon photo diode D1 is by product
Point and level-one amplifier be converted into amplification voltage pulse signal, then through filter condenser C2 blocking, filter out the direct current being wherein mingled with
Obtained after interference signal with by irradiation corresponding and stable voltage pulse signal " SIG " by force；
5 main body of analog switching circuit is a dual analog being made of analog switch modules A and analog switch module B
Switch integrated chip U2, in which: 2.5V working power input pin VCC, voltage pulse are provided in the analog switch modules A
The arteries and veins that signal " SIG " accesses foot NOA, NR68 signal output pin COMA, signal input grounding foot NCA and provided by microcontroller
The access of punching control signal M1 controls foot INA；Power ground foot GND is provided in the analog switch module 2, by microcontroller
The access control foot INB for the pulse control signal M2 that device provides, voltage pulse signal " SIG " access foot NCB, NR66 signal output
Foot COMB and signal input grounding foot NOB, is provided on the working power input pin VCC by magnetic bead B3 and capacitor
The filter circuit that C7, C8 are constituted；When work, the pulse control signal M1 and M2 provided by microcontroller is respectively through INA foot and INB
Foot input, voltage pulse signal " SIG " is inputted through NOA foot and NCB foot respectively, by pulse control signal M1 and M2 control switch
Movement, wherein the pulse control signal M1 and M2 is identical as the light source drive signal period in light control system, phase phase difference
Certain angle, with certain duty ratio, input can be cut into voltage pulse signal " SIG " after passing through analog switching circuit and arteries and veins
The identical voltage pulse signal " NR68 " of punching control signal M1 and M2 duty ratio and " NR66 " output；
2 main body of operational amplifier circuit is the integration module that one includes amplifier comparison module A and operational amplifier filter B
Signal input pin+INA and reverse signal input pin-INA in the same direction, power supply wiring are provided on U3, the amplifier comparison module A
Signal input pin+INB and reverse signal in the same direction are provided on foot V- and signal output pin OUTA, the operational amplifier filter B
Input pin-INB, power supply wiring foot V+ and signal output pin OUTB, in which: in amplifier comparison module A, the signal in the same direction
Input pin+INA is upper while being connected to one end of resistance R3 and resistance R4 and NR4 feedback signal acquisition contact altogether, and resistance R3's is another
The electric terminal of NR68, the other end ground connection of resistance R4 are provided on end；Reverse signal input pin-the INA is upper while total
It is connected to one end of resistance R5 and resistance R6, input electric terminal NR66 is provided on the other end of resistance R5, resistance R6's is another
It holds and is connected with the signal output pin OUTA for being equipped with ABS output signal contact, thus constituting an operation result is ABS output letter
Number subtraction circuit, in addition, being provided with the filter being made of magnetic bead B3 and capacitor C9 and C10 on the power supply wiring foot V-
Wave circuit；In operational amplifier filter B, the signal input pin+INB in the same direction is grounded by capacitor C11, while passing through electricity
One end of one end and resistance R8 for hindering R7 and capacitor C12 mutually connects altogether, in the other end and amplifier comparison module A of resistance R8
ABS output signal contact is connected, the other end of capacitor C12 simultaneously with the signal output pin OUTB that is equipped with output contact AD4
It connects and is connected altogether with one end of resistance R9, the other end of resistance R9 while one end with reverse signal input pin-INB and resistance R10
Connected, the other end ground connection of resistance R10 is connect altogether, thus one low-pass filter circuit of composition, furthermore the power supply wiring foot V
+ above it is provided with the filter circuit being made of resistance B5 and capacitor C14 and C15；When work, subtraction circuit will be by analog switch
Circuit 5 cuts two pulse voltage signals " NR68 " identical with pulse control signal M1 and M2 duty ratio provided and " NR66 "
Synthesis output ABS pulse signal, pulse signal finally be converted into being exported, just by output contact AD4 by low-pass filter circuit
It acquired in A/D acquisition unit 3, send the stable level signal that microcontroller carries out real-time intensity control to.
Claims (1)
1. a kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit, main body include silicon photo diode (1), operational amplifier circuit
(2) and A/D acquisition unit (3), it is characterised in that: also include current/voltage-converted unit (4) and mould in photoelectric detective circuit
Quasi- switching circuit (5), in which:
Current/voltage-converted unit (4) main body is one equipped with signal input pin+IN in the same direction, reverse signal input pin-
Amplifier the integration module U1, the working power input pin V of IN, signal output pin OUT and working power input pin V+ and V-
+ it is above provided with the filter circuit being made of magnetic bead B1 and capacitor C3 and C4, it is provided on the working power input pin V-
The filter circuit being made of magnetic bead B2 and capacitor C5 and C6, the described signal input pin+IN in the same direction ground connection, and with two pole of silicon light
The anode of pipe D1 is connected, and the reverse signal input pin-IN is connected with the cathode of silicon photo diode D1, and with by resistance R1 and
The connects end altogether that capacitor C1 parallel connection constitutes integrating circuit is connected, another connects end altogether of integrating circuit is removed and signal output pin
Outside OUT is connected, also it is grounded by concatenated blocking filter condenser C2 and pull down resistor R2, and in filter condenser C2 and drop-down
The output contact of voltage signal " SIG " is provided on the interface point of resistance R2；
Analog switching circuit (5) main body is opened for one by the dual analog that analog switch modules A and analog switch module B are constituted
Close integrated chip U2, in which: 2.5V working power input pin VCC, voltage pulse letter are provided in the analog switch modules A
Number " SIG " access foot NOA, NR68 signal output pin COMA, signal input grounding foot NCA and the pulse provided by microcontroller
The access for controlling signal M1 controls foot INA；Power ground foot GND is provided in the analog switch module 2, by microcontroller
Access control foot INB, the voltage pulse signal " SIG " of the pulse control signal M2 of offer accesses foot NCB, NR66 signal output pin
COMB and signal input grounding foot NOB, be provided on the working power input pin VCC by magnetic bead B3 and capacitor C7,
The filter circuit that C8 is constituted；
Operational amplifier circuit (2) main body is the integration module U3 that one includes amplifier comparison module A and operational amplifier filter B,
Signal input pin+INA and reverse signal input pin-INA in the same direction, power supply wiring foot are provided on the amplifier comparison module A
It is defeated that signal input pin+INB and reverse signal in the same direction are provided on V- and signal output pin OUTA, the operational amplifier filter B
Enter foot-INB, power supply wiring foot V+ and signal output pin OUTB, in which: in amplifier comparison module A, the signal in the same direction is defeated
Enter one end and NR4 feedback signal acquisition contact that foot+INA above while is altogether connected to resistance R3 and resistance R4, the other end of resistance R3
On be provided with the electric terminal of NR68, the other end ground connection of resistance R4；Reverse signal input pin-the INA is upper while connecing altogether
There are one end of resistance R5 and resistance R6, input electric terminal NR66, the other end of resistance R6 are provided on the other end of resistance R5
It is connected with the signal output pin OUTA for being equipped with ABS output signal contact, thus constituting an operation result is ABS output signal
Subtraction circuit, in addition, being provided with the filtering being made of magnetic bead B3 and capacitor C9 and C10 on the power supply wiring foot V-
Circuit；In operational amplifier filter B, the signal input pin+INB in the same direction is grounded by capacitor C11, while passing through resistance
One end of R7 and capacitor C12 and one end of resistance R8 mutually connect altogether, the other end and the ABS in amplifier comparison module A of resistance R8
Output signal contact is connected, the other end of capacitor C12 simultaneously with the signal output pin OUTB and electricity that are equipped with output contact AD4
One end of resistance R9 connects connected altogether, and the other end of resistance R9 connects with one end of reverse signal input pin-INB and resistance R10 altogether simultaneously
It is connected, thus the other end ground connection of resistance R10 constitutes a low-pass filter circuit, furthermore on the power supply wiring foot V+
It is provided with the filter circuit being made of resistance B5 and capacitor C14 and C15.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820997332.5U CN208283224U (en) | 2018-06-27 | 2018-06-27 | A kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820997332.5U CN208283224U (en) | 2018-06-27 | 2018-06-27 | A kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit |
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| Publication Number | Publication Date |
|---|---|
| CN208283224U true CN208283224U (en) | 2018-12-25 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201820997332.5U Expired - Fee Related CN208283224U (en) | 2018-06-27 | 2018-06-27 | A kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108844864A (en) * | 2018-06-27 | 2018-11-20 | 苏州汉策能源设备有限公司 | A kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit |
-
2018
- 2018-06-27 CN CN201820997332.5U patent/CN208283224U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108844864A (en) * | 2018-06-27 | 2018-11-20 | 苏州汉策能源设备有限公司 | A kind of preceding scattering dust measurement instrument sample gas pond photoelectric detective circuit |
| CN108844864B (en) * | 2018-06-27 | 2024-07-12 | 李斌 | Photoelectric detection circuit for sample gas cell of front scattering dust meter |
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