CN107612513A - A kind of low level signal amplification device - Google Patents
A kind of low level signal amplification device Download PDFInfo
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- CN107612513A CN107612513A CN201710794677.0A CN201710794677A CN107612513A CN 107612513 A CN107612513 A CN 107612513A CN 201710794677 A CN201710794677 A CN 201710794677A CN 107612513 A CN107612513 A CN 107612513A
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Abstract
The present invention discloses a kind of low level signal amplification device, solves the problems, such as that existing low level signal amplification system noise is big, circuit is complicated, cost is high.Described device includes power supply processing unit and signal amplification filter unit, and signal amplification filter unit includes first, second emitter follower, the first order, the second level, third level amplifier, bandpass filter, first, second trapper.First emitter follower receives small-signal, and export and give first order amplifier, bandpass filter filters to first order amplifier output signal, second level amplifier accepts filter output signal, first trapper filters out interference to second level amplifier output signal, and the second trapper filters out interference to the first trapper output signal, and third level amplifier receives the second trapper output signal, second emitter follower receives third level amplifier output signal, exports amplified signal;Power supply processing unit is to signal amplification filter unit power supply.Low level signal amplification device cost performance that the present invention realizes is good, signal to noise ratio is high, portable strong.
Description
Technical field
The present invention relates to electric field, more particularly to a kind of low level signal amplification device.
Background technology
With the extensive use of sensor, the various faint small-signals of sensor output, as Dim light measurement, thin tail sheep are examined
Survey, tepor difference detection etc., are increasingly valued by people, the control signal obtained from various sensors, typically only several mV
Or it is smaller, and any microvibration of surrounding or electromagnetic interference and ground wire noise are likely to the very big ripple for causing measurement result
It is dynamic, cause the accuracy of measurement.Because signal is very faint, it must be amplified before being measured to it, it is existing
There is an operational amplifier and the introduced noise of sampling apparatus is probably tens times of signal to be detected even hundreds of times, thus can not
Common amplifier is directly selected, otherwise the noise of amplifier in itself may flood actual signal.By circuit system line
Limitation often be present in the limitation of sex work scope, traditional small-signal amplification method, simultaneously as amplifier offset error
Influence and make it that circuit is extremely complex, debugging is difficult, circuit cost is higher.
The content of the invention
The present invention provides a kind of low level signal amplification device, solves that existing low level signal amplification system noise is big, circuit is complicated, adjusts
The problem of examination is difficult, cost is high.
The embodiment of the present invention provides a kind of low level signal amplification device, single comprising power supply processing unit and signal amplification filtering
Member, signal amplification filter unit include the first emitter follower, first order amplifier, bandpass filter, second level amplifier, the
One trapper, the second trapper, third level amplifier, the second emitter follower;First emitter follower is used to receive small-signal;It is described
First order amplifier is used for the signal for receiving the first emitter follower output;The bandpass filter is used to put the first order
The signal filtering of big device output;The second level amplifier is used for the signal for receiving the bandpass filter output;Described first
Trapper is used for the Hz noise of target signal filter first to second level amplifier output;Second trapper is used for institute
State the Hz noise of target signal filter second of the first trapper output;The third level amplifier is used to receive second trapper
The signal of output;Second emitter follower is used for the signal for receiving the third level amplifier output, exports amplified signal;It is described
Power supply processing unit is used to, to signal amplification filter unit power supply, respectively with the first order, the second level, the third level amplify
Device, bandpass filter, the first trapper, the connection of the second trapper.
Further, the power supply processing unit is also comprising voltage regulator, the second triode, the 5th resistance, the 6th electricity
Resistance, the 7th resistance, the 8th electric capacity, the 9th electric capacity, the tenth electric capacity, the model MC1723 of the voltage regulator, described second
The model TIP122 of triode;First, the eight, the nine, the 14th pins difference of the voltage regulator is hanging, the 5th pipe
Pin is connected with the 6th pin, the 11st pin be connected with the 12nd pin and with input positive supply, the 9th electric capacity one end, described the
The colelctor electrode connection of two triodes, the tenth pin is connected with the base stage of second triode, the second pin and the described 2nd 3
The emitter stage of pole pipe, the connection of the 5th resistance one end, three-prong and the 5th resistance other end, the 7th resistance one end, the tenth
Electric capacity one end connects, and exports positive power signal, the 4th pin and described 8th electric capacity one end, the 7th resistance other end, the 6th
Resistance one end is connected, and the tenth three-prong is connected with the 8th electric capacity other end;The 9th electric capacity other end, the 6th electricity
The other end, the tenth electric capacity other end are hindered respectively with being digitally connected.
Preferably, the power supply processing unit also comprising voltage regulator, 3rd resistor, the 4th resistance, the first triode,
6th electric capacity, the 7th electric capacity, diode, the model MC1723 of the voltage regulator, the model of second triode
TIP122;The voltage regulator first, the 8th, second, third, the nine, the 14th pins distinguish hanging, the 11st pin
It is connected with the 12nd pin and with being digitally connected, the 5th pin is connected with the 6th pin, the 7th pin and the one or three pole
Pipe collector, the 6th electric capacity one end, the connection of the 4th resistance one end, and negative power signal is exported, the 4th pin and the described 7th electricity
Holding one end, the 4th resistance other end, the connection of 3rd resistor one end, the tenth three-prong is connected with the 7th electric capacity other end, the
Ten pins are connected with the diode cathode;First transistor base, emitter stage respectively with the diode cathode, described
Input negative supply connection;The 3rd resistor other end, the 6th electric capacity other end are respectively with being digitally connected.
Preferably, the first order amplifier, second level amplifier, the model of third level amplifier are AD797.
Preferably, the bandpass filter includes first, second integrated transporting discharging, the 17th, 18 resistance, the 32nd,
33,34,35,38,39 resistance, the three, the 38th, 39,50,51,50
2nd, 53 electric capacity, the model OP37G of first, second integrated transporting discharging;The first, the 8th of first integrated transporting discharging
Pin is hanging, and the second pin is connected with described 50th electric capacity one end, the 34th resistance one end, three-prong and the described 3rd
18 resistance are adjustable end, the 38th resistance fixing end, digitally connect, the seven, the 4th pins are handled with the power supply respectively
The positive and negative power supply signal connection of unit output, the 6th pin and the 34th resistance other end, the 38th electric capacity one
End, the connection of the 51st electric capacity one end;The 50th electric capacity other end and described 32nd resistance one end, the 38th electricity
Hinder another fixing end connection;The 32nd resistance other end is used for the signal for receiving the first order amplifier output;Institute
The 38th electric capacity other end is stated to be connected with described 17th resistance one end, the 33rd resistance one end;17th resistance
The other end is with being digitally connected;The 33rd resistance other end and described 52nd electric capacity one end, the 53rd electric capacity
One end, the connection of the 39th resistance fixing end;First, the 8th pin of second integrated transporting discharging is hanging, the second pin and institute
State the 52nd electric capacity other end, the connection of the 35th resistance one end, three-prong and the adjustable end of the 39th resistance, the
Another fixing end of 39 resistance, digitally connect, the seven, the 4th pins respectively with the power supply processing unit output just,
Negative power signal connects, the 6th pin and the 35th resistance other end, the 39th electric capacity one end, the 53rd electric capacity
The other end connects;The 39th electric capacity other end is connected with described 18th resistance one end, the 3rd electric capacity one end, and is exported
Filtered signal;The 18th resistance other end, the 3rd electric capacity other end are respectively with being digitally connected.
Preferably, first trapper includes the three, the 4th integrated transporting dischargings, model OP37G, the 20th, 21,
22,23 resistance, the 41st, 42,45 electric capacity;First, the 8th pin of the 3rd integrated transporting discharging
Hanging respectively, positive and negative power supply signal of the seven, the 4th pins respectively with power supply processing unit output is connected, the second pin
It is connected with the 6th pin, the 23rd resistance fixing end, and the signal after the first Hz noise, three-prong is filtered out for exporting
It is connected with the 21st resistance one end, 42 electric capacity one end;First, the 8th pin of the 4th integrated transporting discharging hangs respectively
Sky, positive and negative power supply signal of the seven, the 4th pins respectively with power supply processing unit output are connected, the second pin and the 6th
Pin, the 45th electric capacity one end, the connection of the 22nd resistance one end, three-prong are connected with the 23rd adjustable end of resistance;
Another fixing end of 23rd resistance is with being digitally connected;The 21st resistance other end and the described 45th electricity
Hold the other end, the connection of the 20th resistance one end;The 22nd resistance other end is connected with described 41st electric capacity one end;
The 20th resistance other end is connected with the 41st electric capacity other end, and defeated for receiving the second level amplifier
The signal gone out.
Further, second trapper includes the five, the 6th integrated transporting dischargings, model OP37G, and the 24th, two
16,27,28 resistance, the 43rd, 44,46,48 electric capacity;The of 5th integrated transporting discharging
First, the 8th pin difference is hanging, and positive and negative power supply signal of the seven, the 4th pins respectively with power supply processing unit output connects
Connect, the second pin is connected with the 6th pin, the 48th electric capacity one end, the 24th resistance fixing end, three-prong and second
17 resistance one end, the connection of 44 electric capacity one end;The first, the 8th pin difference of 4th integrated transporting discharging is hanging, the 7th,
Positive and negative power supply signal of 4th pin respectively with power supply processing unit output is connected, the second pin and the 6th pin, the 4th
16 electric capacity one end, the connection of the 28th resistance one end, three-prong are connected with the 24th adjustable end of resistance;Described 20th
Another fixing end of four resistance is with being digitally connected;The 27th resistance other end and the 46th electric capacity other end,
26th resistance one end connects;The 28th resistance other end is connected with described 43rd electric capacity one end;Described
The 26 resistance other ends are connected with the 43rd electric capacity other end, and for receiving the letter of the first trapper output
Number;The 48th electric capacity other end, which is used to export, filters out the signal after the second Hz noise.
Further, the third level amplifier also comprising the 13rd, 14,16,31,36,37,
15,26,27 resistance, the 37th, 48,49,40 electric capacity, the 3rd emitter follower model AD797;
The first pin, the 5th pin, the 8th pin of the third level amplifier are hanging, the 7th pin, the 4th pin respectively with it is described
The positive and negative power supply signal connection of power supply processing unit output, the second pin and described 13rd resistance one end, the 31st resistance
One end is connected, and three-prong is connected with described 14th resistance one end, the 6th pin and described 37th electric capacity one end, the 3rd
The 11 resistance other ends connect;The first pin, the 5th pin, the 8th pin of 3rd emitter follower are hanging, the 7th pin,
Positive and negative power supply signal of four pins respectively with power supply processing unit output is connected, the second pin and the described 37th electricity
One end, the connection of the 49th electric capacity one end are hindered, three-prong connects with described 36th resistance one end, the 48th electric capacity one end
Connect, the 6th pin is connected with described 40th electric capacity one end, the 37th resistance other end, the 49th electric capacity other end;Institute
The 13rd resistance other end is stated with being digitally connected;The 14th resistance other end is used to receive the second trapper output
Signal;The 37th electric capacity other end is connected with the 36th resistance other end, the 16th resistance one end;It is described
The 16th resistance other end, the 48th electric capacity other end are respectively with being digitally connected;The 40th electric capacity other end and institute
The 15th resistance one end, the 26th resistance one end, the connection of the 27th resistance one end are stated, and exports the amplified signal;Institute
The 15th resistance other end, the 26th resistance other end, the 27th resistance other end are stated respectively with being digitally connected.
Preferably, the gain of the first order amplifier is 20dB, and the gain of the second level amplifier is 35dB, described
The gain of third level amplifier is 20dB.
Preferably, the electric capacity is from styrene, silvered mica capacitor, NP0 ceramic electricals perhaps tantalum electric capacity, the resistance choosing
Use metalfilmresistor.
Beneficial effect of the present invention includes:The low level signal amplification device that the present invention designs can be by microvolt to the faint of millivolt level
Electric signal is enlarged into volt level signal, solves the problems, such as faint low level signal amplification, additionally it is possible to the signal after amplification is filtered, filtered out
Noise and Hz noise, it is easy to relevant treatment of the follow-up signal processing unit to reception signal, while the small letter that the present invention designs
Number amplifying device cost performance is good, signal to noise ratio is high, portable strong.
Brief description of the drawings
Accompanying drawing described herein is used for providing a further understanding of the present invention, forms the part of the present invention, this hair
Bright schematic description and description is used to explain the present invention, does not form inappropriate limitation of the present invention.In the accompanying drawings:
Fig. 1 is a kind of low level signal amplification device embodiment;
Fig. 2 is that a kind of signal amplifies filter unit embodiment;
Fig. 3 is a kind of power supply processing unit embodiment comprising positive voltage signal;
Fig. 4 is a kind of power supply processing unit embodiment comprising negative voltage signal;
Fig. 5 is a kind of bandpass filter embodiment;
Fig. 6 is a kind of first trap embodiment;
Fig. 7 is a kind of second trap embodiment;
Fig. 8 is a kind of signal amplification circuit embodiment.
Embodiment
To make the object, technical solutions and advantages of the present invention clearer, below in conjunction with the specific embodiment of the invention and
Technical solution of the present invention is clearly and completely described corresponding accompanying drawing.Obviously, described embodiment is only the present invention one
Section Example, rather than whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art are not doing
Go out under the premise of creative work the every other embodiment obtained, belong to the scope of protection of the invention.
Below in conjunction with accompanying drawing, the technical scheme that various embodiments of the present invention provide is described in detail.
Fig. 1 is a kind of low level signal amplification device embodiment.The embodiment of the present invention provides a kind of low level signal amplification device, comprising
Power supply processing unit 1 and signal amplification filter unit 2, the signal amplification filter unit includes the first emitter follower 3, the first order is put
Big device 4, bandpass filter 5, second level amplifier 6, the first trapper 7, the second trapper 8, third level amplifier 9, second are penetrated
With device 10;First emitter follower is used to receive small-signal;The first order amplifier is defeated for receiving first emitter follower
The signal gone out;The bandpass filter is used to filter the signal of first order amplifier output;The second level amplifier
For receiving the signal of the bandpass filter output;First trapper is used for the letter to second level amplifier output
Number filter out the first Hz noise;Second trapper is used to do the power frequency of target signal filter second of first trapper output
Disturb;The third level amplifier is used for the signal for receiving the second trapper output;Second emitter follower is used to receive institute
The signal of third level amplifier output is stated, exports amplified signal;The power supply processing unit, which is used to amplify the signal, to be filtered
Unit power, respectively with the first order, the second level, third level amplifier, bandpass filter, the first trapper, the second trap
Device connects.
Preferably, the gain of the first order amplifier is 20dB, and the gain of the second level amplifier is 35dB, described
The gain of third level amplifier is 20dB.
Preferably, the first order amplifier, second level amplifier, the model of third level amplifier are AD797, common mode
Rejection ratio is high.
In embodiments of the present invention, the input small signal levels of selection are -70dBm, i.e. virtual value is 0.2mV, the letter
Number amplification filter unit overall gain be 75dB, i.e., multiplication factor be 5700 times, it is necessary to explanation, input small signal levels value
It can also be other amplitudes, be not particularly limited here, it should be noted that, the overall gain of the signal amplification filter unit
Can be other values, concrete numerical value is relevant with the selection of amplifier, is not specially limited here.
In embodiments of the present invention, the mode of secondary pressure is employed in the power supply processing unit improve circuits at different levels and lead to
Noise jamming caused by electric power loop is crossed, power supply ripple is decreased below 10mV ranks by hundred mV ranks.
It should be noted that the index of the low level signal amplification device of design of the embodiment of the present invention can reach, centre frequency
50kHz, gain amplifier are not less than 75dB, bandwidth 1Hz, 50 ohm of input impedance.
The ultra-weak electronic signal of microvolt to millivolt level can be enlarged into Fu Jixin by the low level signal amplification device that the present invention designs
Number, solve the problems, such as faint low level signal amplification, additionally it is possible to the signal after amplification is filtered, filters out noise and Hz noise, just
Relevant treatment in follow-up signal processing unit to reception signal.
Fig. 2 is that a kind of signal amplifies filter unit embodiment.The embodiment of the present invention provides a kind of signal amplification filter unit,
The signal amplification filter unit includes the first emitter follower, first order amplifier, bandpass filter, second level amplifier, first
Trapper, the second trapper, third level amplifier, the second emitter follower;First emitter follower is used to receive small-signal;Described
First stage amplifier is used for the signal for receiving the emitter follower output;The bandpass filter is used for defeated to the first order amplifier
The signal filtering gone out;The second level amplifier is used for the signal for receiving the bandpass filter output;First trapper
For the Hz noise of target signal filter first exported to the second level amplifier;Second trapper is used for described first
The Hz noise of target signal filter second of trapper output;The third level amplifier is used to receive the second trapper output
Signal;Second emitter follower is used for the signal for receiving the third level amplifier output, exports amplified signal.
It should be noted that amplifying circuit is low noise amplification and narrow-band filtering circuit, have very big dynamic range and
The good linearity and stable gain.Put the first order amplifying circuit that amplifier is whole narrow-band receiver in advance.Due to system
Very high technical indicator is proposed, so also having very high index request to the first order of amplifier.For the level of N level amplifiers
Connection, whole noise coefficient can be determined by below equation:
Wherein FiFor the noise coefficient of i-stage amplifier, GAiFor the gain of i-stage amplifier.
Therefore, the noise coefficient of whole invention design depends primarily on first order amplifier, so selected by the partial circuit
The noise coefficient of first order amplifier is most critical.Because the incoming signal level of the present invention is very weak, the first order is advance
Amplifier proposes higher technical requirement, to there is higher sensitivity and ultralow noise coefficient.
It should be noted that the low level signal amplification device of the present invention uses three-level amplification side in signal amplification filter unit
Formula, add one-level emitter follower to be isolated in input and output end lattice, be then amplified filtering again.Whole circuit design is made an uproar
Sonic system number depends primarily on first order amplifier, so the noise coefficient of the first order amplifier selected by the partial circuit is most
Crucial.The second level amplifier is interstage amplifier section, is placed on after the bandpass filtering, before first trapper;
The third level amplifier is final amplification stage, after second trapper.Advantage of this is that the signal of input is very
It is weak, and be superimposed with noise, if input stage multiplication factor is too big, noise and signal will be exaggerated together, then noise quilt
Strengthen, be not easy to rear class and remove noise;The signal tentatively amplified noise and interference after bandpass filter are effectively suppressed,
The signal is sent to interstage amplifier section again and does further amplification, final stage is a kind of supplement amplification, with thermal compensation signal in the transmission
Loss.Dual-stage amplifier uses typical in-phase proportion amplifier afterwards.The gain of whole amplifying circuit is equal to gain per stage
Product.
It should be noted that gain per stage of the embodiment of the present invention is respectively set to, input stage 20dB, intergrade is
40dB, final stage 20dB, the overall gain of circuit is 80dB, it is possible to use other gains are set, and are not specifically limited here.
Amplifier of the embodiment of the present invention uses AD797, and it has in 1kHz as little asInput noise voltage,
In 20kHz, as little as -120dB total harmonic distortion closes 130dB common-mode rejection ratio, controls drawn in itself by amplifier well
The noise entered, the influence of the reduction noise of high degree to signal.
Fig. 3 is a kind of power supply processing unit embodiment comprising positive voltage signal.The embodiment of the present invention provides a kind of power supply
Processing unit, the power supply processing unit is also comprising voltage regulator, the second triode, the 5th resistance, the 6th resistance, the 7th electricity
Resistance, the 8th electric capacity, the 9th electric capacity, the tenth electric capacity, the model MC1723 of the voltage regulator, the type of second triode
Number it is TIP122;First, the eight, the nine, the 14th pins difference of the voltage regulator is hanging, the 5th pin and the 6th pipe
Pin connects, and the 11st pin is connected with the 12nd pin and with inputting positive supply, the 9th electric capacity one end, second triode
Colelctor electrode is connected, and the tenth pin is connected with the base stage of second triode, the transmitting of the second pin and second triode
Pole, the connection of the 5th resistance one end, three-prong connect with the 5th resistance other end, the 7th resistance one end, the tenth electric capacity one end
Connect, and export positive power signal, the 4th pin connects with described 8th electric capacity one end, the 7th resistance other end, the 6th resistance one end
Connect, the tenth three-prong is connected with the 8th electric capacity other end;The 9th electric capacity other end, the 6th resistance other end,
The tenth electric capacity other end is respectively with being digitally connected.
Preferably, the electric capacity is from styrene, silvered mica capacitor, NP0 ceramic electricals perhaps tantalum electric capacity, the resistance choosing
Use metalfilmresistor.
It should be noted that the ceramic condenser of the styrene, silvered mica capacitor and NPO, its temperature coefficient are
50ppm/℃;The temperature coefficient of polytetrafluoroethylene (PTFE) and polyester resin electric capacity is 150ppm/ DEG C, less demanding or at a puss may be used
To select tantalum electric capacity, alminium electrolytic condenser can not be definitely used.The metalfilmresistor, its temperature coefficient are within 150ppm/ DEG C.
Power supply processing unit described in the embodiment of the present invention employs the mode of secondary pressure, and it is double that prime employs positive and negative 20V
Linear direct-flow voltage regulation source, output+15V voltage signals are used to give signal amplification filter unit power supply.The model
MC1723 voltage regulator can provide 150mA load current, and its output current can be expanded by external transistor
Several amperes of levels are opened up, its output voltage can be adjusted from 2Vdc to 37Vdc, and with 0.01% linearity.Its
The average temperature coefficient 0.002% of output voltage, the Ripple Suppression in 50Hz~10kHz frequency range can reach 86dB,
100Hz~10kHz output noises voltage is 2.5 μ V.
In embodiments of the present invention, the resistance of the 5th resistance R5 is 0.55 Europe, and the resistance of the 6th resistance R6 is
10k Europe, the resistance of the 7th resistance R7 is 12k Europe, and the capacitance of the 8th electric capacity C8 is 100pF, the 9th electric capacity C9
Capacitance be 0.1uF, the capacitance of the tenth electric capacity C10 is 10uF.
In the embodiment of the present invention, power supply ripple is less than 10mV ranks by changing using preceding hundred mV ranks after being down to use,
Effectively inhibit noise jamming caused by power circuit.
Fig. 4 is a kind of power supply processing unit embodiment comprising negative voltage signal.The embodiment of the present invention provides a kind of power supply
Processing unit, the power supply processing unit is also comprising voltage regulator, 3rd resistor, the 4th resistance, the first triode, the 6th electricity
Appearance, the 7th electric capacity, diode, the model MC1723, the model TIP122 of second triode of the voltage regulator;
The voltage regulator first, the 8th, second, third, the nine, the 14th pins distinguish hanging, the 11st pin and the tenth
Two pins are connected and with being digitally connected, and the 5th pin is connected with the 6th pin, the 7th pin and the first triode current collection
Pole, the 6th electric capacity one end, the connection of the 4th resistance one end, and export negative power signal, the 4th pin and described 7th electric capacity one end,
The 4th resistance other end, the connection of 3rd resistor one end, the tenth three-prong is connected with the 7th electric capacity other end, the tenth pin and
The diode cathode connection;First transistor base, emitter stage respectively with the diode cathode, the input negative electricity
Source connects;The 3rd resistor other end, the 6th electric capacity other end are respectively with being digitally connected.
In embodiments of the present invention, the capacitance of the 7th electric capacity C7 is 100pF, and the capacitance of the 6th electric capacity C6 is
10uF, the 3rd resistor R3 resistance are 12K Europe, and the resistance of the 4th resistance is 10k Europe.
Preferably, the electric capacity is from styrene, silvered mica capacitor, NP0 ceramic electricals perhaps tantalum electric capacity, the resistance choosing
Use metalfilmresistor.
Power supply processing unit described in the embodiment of the present invention employs the mode of secondary pressure, and it is double that prime employs positive and negative 20V
Linear direct-flow voltage regulation source, output -15V voltage signals are used to give signal amplification filter unit power supply.
Fig. 5 is a kind of bandpass filter embodiment.The embodiment of the present invention provides a kind of bandpass filter, for the small letter
The signal amplification filter unit of number amplifying device, the bandpass filter include first, second integrated transporting discharging, and the 17th, 18
Resistance, the 32nd, 33,34,35,38,39 resistance, the three, the 38th, 39, five
Tenth, 51,52,53 electric capacity, the model OP37G of first, second integrated transporting discharging;Described first integrated fortune
The first, the 8th pin put is hanging, and the second pin is connected with described 50th electric capacity one end, the 34th resistance one end, and the 3rd
Pin is adjustable with the 38th resistance end, the 38th resistance fixing end, digitally it is connected, the seven, the 4th pins difference
Be connected with the positive and negative power supply signal of power supply processing unit output, the 6th pin and the 34th resistance other end, the
38 electric capacity one end, the connection of the 51st electric capacity one end;The 50th electric capacity other end and the 32nd resistance one
End, another fixing end connection of the 38th resistance;The 32nd resistance other end is used to receive the first order amplifier
The signal of output;The 38th electric capacity other end is connected with described 17th resistance one end, the 33rd resistance one end;Institute
The 17th resistance other end is stated with being digitally connected;The 33rd resistance other end and described 52nd electric capacity one end,
53rd electric capacity one end, the connection of the 39th resistance fixing end;First, the 8th pin of second integrated transporting discharging is hanging,
Second pin is connected with the 52nd electric capacity other end, the 35th resistance one end, three-prong and the described 39th
Resistance is adjustable end, another fixing end of the 39th resistance, digitally connect, the seven, the 4th pins are handled with the power supply respectively
The positive and negative power supply signal connection of unit output, the 6th pin and the 35th resistance other end, the 39th electric capacity one
End, the connection of the 53rd electric capacity other end;The 39th electric capacity other end and described 18th resistance one end, the 3rd electric capacity
One end connects, and exports filtered signal;The 18th resistance other end, the 3rd electric capacity other end are respectively with digitally connecting
Connect.
In embodiments of the present invention, the resistance of the 32nd resistance R32 is 36k Europe, the 34th R34 resistance
Resistance be 240k Europe, the resistance of the 33rd resistance R33 is 36k Europe, and the resistance of the 35th resistance R35 is
240k Europe, the resistance of the 18th resistance R18 is 2k Europe, and the 38th resistance R38, the 39th resistance R39 are can
Adjust resistance, the 50th electric capacity C50, the 51st electric capacity C51, the 52nd electric capacity C52, the described 53rd
Electric capacity C53 capacitance is 1nF, and the 38th electric capacity C38, the capacitance of the 39th electric capacity C39 are 1uF, institute
The capacitance for stating the 3rd electric capacity BAK3 is 0.1uF
It should be noted that the embodiment of the present invention employs 50kHz active band-pass filter, other passbands can be also used
The bandpass filter of frequency, is not specially limited here.
The Q values of wave filter are improved by the way of two stage filter in 50kHz active band-pass filter circuit design,
Resistance by adjusting described resistance R38, R39 reaches the purpose of adjustment filter centre frequency, by adjusting the resistance
R34, R32 ratio, the bandwidth of described resistance R35, R33 ratio adjustment bandpass filter and gain, bandwidth is narrower, and gain is got over
It is high.Active filter will keep prolonged stability, depend primarily on the performance of resistance and electric capacity, therefore in selection component
When strict selection is carried out according to use.The pottery of prioritizing selection styrene, silvered mica capacitor and NPO in terms of electric capacity is selected
Porcelain electric capacity, its temperature coefficient are 50ppm/ DEG C;The temperature coefficient of polytetrafluoroethylene (PTFE) and polyester resin electric capacity is 150ppm/ DEG C;
It is less demanding or tantalum electric capacity can be selected at a puss, it can not definitely use alminium electrolytic condenser.Should be preferential in terms of resistance selection
Metalfilmresistor is selected, its temperature coefficient is within 150ppm/ DEG C.
Fig. 6 is a kind of first trap embodiment.The embodiment of the present invention provides a kind of trapper, is put for the small-signal
The signal amplification filter unit of big device, first trapper include the three, the 4th integrated transporting dischargings, model OP37G, and second
Tenth, 21,22,23 resistance, the 41st, 42,45 electric capacity;The of 3rd integrated transporting discharging
First, the 8th pin difference is hanging, and positive and negative power supply signal of the seven, the 4th pins respectively with power supply processing unit output connects
Connect, the second pin is connected with the 6th pin, the 23rd resistance fixing end, and filters out the letter after the first Hz noise for exporting
Number, three-prong is connected with the 21st resistance one end, 42 electric capacity one end;The first, the 8th of 4th integrated transporting discharging
Pin difference is hanging, and positive and negative power supply signal of the seven, the 4th pins respectively with power supply processing unit output is connected, and second
Pin is connected with the 6th pin, the 45th electric capacity one end, the 22nd resistance one end, and three-prong and the 23rd resistance can
Adjust end connection;Another fixing end of 23rd resistance is with being digitally connected;The 21st resistance other end with it is described
The 45th electric capacity other end, the connection of the 20th resistance one end;The 22nd resistance other end and the described 41st electricity
Hold one end connection;The 20th resistance other end is connected with the 41st electric capacity other end, and for receiving described the
The signal of two-stage amplifier output.
The trap circuit of first trapper described in the embodiment of the present invention is using double T trap circuits, the 20th R20, the
21 resistance R21 resistance is 9.6K Europe, and the resistance of the 22nd resistance R22 is 4.7k Europe, the 23rd electricity
Resistance R23 is adjustable resistance, and maximum value is 2k Europe, and the 41st electric capacity C41, the 42nd electric capacity C42 size are
332nF, the Q values of first trapper reach nearly 100, and stopband can reach -65dB, can effectively prevent Hz noise.
Preferably, the electric capacity is from styrene, silvered mica capacitor, NP0 ceramic electricals perhaps tantalum electric capacity, the resistance choosing
Use metalfilmresistor.
It should be noted that the design of the trapper will consider city's electrical interference, due to power frequency can seal in circuit into
For main interference source, therefore to filter out Hz noise.
In embodiments of the present invention, first trapper considers that the mains frequency in China is 50Hz, therefore is designed as
Filter out the trapper of 50Hz Hz noises.
It should be noted that in double T trap circuits, have high requirements for the resistance and electric capacity of circuit, in order that electric
Just at 50Hz, resistance and electric capacity must be selected strictly, it is necessary to adjust the 23rd resistance in circuit the centre frequency on road
R23, it is decayed 50Hz voltage signals maximum, reach and trap effect is only played to 50Hz.
Trapper provided in an embodiment of the present invention can effectively filter out the trap interference that civil power 50Hz is brought, and improve power supply
The ripple of processing unit.
Fig. 7 is a kind of second trap embodiment.The embodiment of the present invention provides a kind of trapper, is put for the small-signal
The signal amplification filter unit of big device, second trapper include the five, the 6th integrated transporting dischargings, model OP37G, and second
14,26,27,28 resistance, the 43rd, 44,46,48 electric capacity;Described 5th is integrated
The first, the 8th pin difference of amplifier is hanging, the positive and negative electricity that the seven, the 4th pins export with the power supply processing unit respectively
Source signal is connected, and the second pin is connected with the 6th pin, the 48th electric capacity one end, the 24th resistance fixing end, the 3rd pipe
Pin is connected with the 27th resistance one end, 44 electric capacity one end;First, the 8th pin of the 4th integrated transporting discharging hangs respectively
Sky, positive and negative power supply signal of the seven, the 4th pins respectively with power supply processing unit output are connected, the second pin and the 6th
Pin, the 46th electric capacity one end, the connection of the 28th resistance one end, three-prong are connected with the 24th adjustable end of resistance;
Another fixing end of 24th resistance is with being digitally connected;The 27th resistance other end and the described 46th electricity
Hold the other end, the connection of the 26th resistance one end;The 28th resistance other end connects with described 43rd electric capacity one end
Connect;The 26th resistance other end is connected with the 43rd electric capacity other end, and for receiving first trap
The signal of device output;The 48th electric capacity other end, which is used to export, filters out the signal after the second Hz noise.
In the embodiment of the present invention, the 26th resistance R26, the 27th resistance R27 resistance are 4.69K Europe, institute
The resistance for stating the 28th resistance R28 is 2.41k Europe, and the 24th resistance is adjustable resistance, and maximum value is 2K Europe, institute
State the 43rd electric capacity C43, the 44th electric capacity C44 capacitance is 332nF, the capacitance of the 46th electric capacity C46 is
675nF, the 48th electric capacity C48 capacitance are 0.1uF.
Preferably, the electric capacity is from styrene, silvered mica capacitor, NP0 ceramic electricals perhaps tantalum electric capacity, the resistance choosing
Use metalfilmresistor.
It should be noted that in double T trap circuits, have high requirements for the resistance and electric capacity of circuit, in order that electric
Just at 100Hz, resistance and electric capacity must be selected strictly, it is necessary to adjust the 24th resistance in circuit the centre frequency on road
R24, it is decayed 100Hz voltage signals maximum, reach and trap effect is only played to 100Hz.
The embodiment of the present invention provides a kind of trapper for the interference of 100Hz traps, can effectively filter out 100Hz traps
Interference, improve power supply processing unit and filter out ability to what 100Hz traps disturbed.
Fig. 8 is a kind of signal amplification circuit embodiment.The embodiment of the present invention provides a kind of signal amplification circuit, for described
In the signal amplification filter unit of low level signal amplification device, the third level amplifier also includes the 13rd, 14,16, three
11,36,37,15,26,27 resistance, the 37th, 48,49,40 electric capacity,
Three emitter follower model AD797;The first pin, the 5th pin, the 8th pin of the third level amplifier are hanging, the 7th pipe
The positive and negative power supply signal of pin, the 4th pin respectively with power supply processing unit output is connected, the second pin and the described 13rd
Resistance one end, the connection of the 31st resistance one end, three-prong is connected with described 14th resistance one end, the 6th pin with it is described
37th electric capacity one end, the connection of the 31st resistance other end;First pin of the 3rd emitter follower, the 5th pin,
Eight pins are hanging, and the positive and negative power supply signal of the 7th pin, the 4th pin respectively with power supply processing unit output is connected, the
Two pins are connected with described 37th resistance one end, the 49th electric capacity one end, three-prong and the 36th resistance
One end, the connection of the 48th electric capacity one end, the 6th pin and described 40th electric capacity one end, the 37th resistance other end, the
The 49 electric capacity other ends connect;The 13rd resistance other end is with being digitally connected;The 14th resistance other end is used
In the signal for receiving the second trapper output;The 37th electric capacity other end and the 36th resistance are another
End, the connection of the 16th resistance one end;The 16th resistance other end, the 48th electric capacity other end are respectively with digitally connecting
Connect;The 40th electric capacity other end and described 15th resistance one end, the 26th resistance one end, the 27th resistance one end
Connection, and export the amplified signal;The 15th resistance other end, the 26th resistance other end, the 27th resistance
The other end is respectively with being digitally connected.
In the embodiment of the present invention, the resistance of the 13rd resistance R13 is 10 Europe, the resistance of the 31st resistance R31
It is worth for 499, the resistance of the 36th resistance R36 is 100 Europe, and the resistance of the 16th resistance R16 is 2k Europe, described
37 resistance R37 resistance is 100 Europe, and the resistance of the 15th resistance R15 is 2k Europe, the 26th resistance R26,
27th resistance R27 resistance is 100 Europe, and the capacitance of the 37th electric capacity C37 is 1uF, the 48th electricity
Appearance C48, the 49th electric capacity C49 capacitance are 30pF, and the capacitance of the 40th electric capacity C48 is 1uF.
Preferably, the electric capacity is from styrene, silvered mica capacitor, NP0 ceramic electricals perhaps tantalum electric capacity, the resistance choosing
Use metalfilmresistor.
It should also be noted that, term " comprising ", "comprising" or its any other variant are intended to nonexcludability
Comprising so that process, method, commodity or equipment including a series of elements not only include those key elements, but also wrapping
Include the other element being not expressly set out, or also include for this process, method, commodity or equipment intrinsic want
Element.In the absence of more restrictions, the key element limited by sentence "including a ...", it is not excluded that wanted including described
Other identical element also be present in the process of element, method, commodity or equipment.
Embodiments of the invention are the foregoing is only, are not intended to limit the invention.For those skilled in the art
For, the present invention can have various modifications and variations.All any modifications made within spirit and principles of the present invention, it is equal
Replace, improve etc., it should be included within scope of the presently claimed invention.
Claims (10)
1. a kind of low level signal amplification device, it is characterised in that include power supply processing unit and signal amplification filter unit;
Signal amplification filter unit include the first emitter follower, first order amplifier, bandpass filter, second level amplifier,
First trapper, the second trapper, third level amplifier, the second emitter follower;
First emitter follower is used to receive small-signal;
The first order amplifier is used for the signal for receiving the first emitter follower output;
The bandpass filter is used to filter the signal of first order amplifier output;
The second level amplifier is used for the signal for receiving the bandpass filter output;
First trapper is used for the Hz noise of target signal filter first to second level amplifier output;
Second trapper is used for the Hz noise of target signal filter second to first trapper output;
The third level amplifier is used for the signal for receiving the second trapper output;
Second emitter follower is used for the signal for receiving the third level amplifier output, exports amplified signal;
The power supply processing unit is used for signal amplification filter unit power supply, respectively with the first order, the second level, the
Third stage amplifier, bandpass filter, the first trapper, the connection of the second trapper.
2. low level signal amplification device as claimed in claim 1, it is characterised in that the power supply processing unit is also adjusted comprising voltage
Save device, the second triode, the 5th resistance, the 6th resistance, the 7th resistance, the 8th electric capacity, the 9th electric capacity, the tenth electric capacity, the electricity
Press the model MC1723, the model TIP122 of second triode of adjuster;
First, the eight, the nine, the 14th pins difference of the voltage regulator is hanging, and the 5th pin is connected with the 6th pin,
11st pin be connected with the 12nd pin and with input positive supply, the 9th electric capacity one end, second triode colelctor electrode
Connection, the tenth pin is connected with the base stage of second triode, the emitter stage of the second pin and second triode, the 5th
Resistance one end is connected, and three-prong is connected with the 5th resistance other end, the 7th resistance one end, the tenth electric capacity one end, and defeated
Going out positive power signal, the 4th pin is connected with described 8th electric capacity one end, the 7th resistance other end, the 6th resistance one end, and the tenth
Three-prong is connected with the 8th electric capacity other end;
The 9th electric capacity other end, the 6th resistance other end, the tenth electric capacity other end are respectively with being digitally connected.
3. low level signal amplification device as claimed in claim 1, it is characterised in that the power supply processing unit is also adjusted comprising voltage
Save device, 3rd resistor, the 4th resistance, the first triode, the 6th electric capacity, the 7th electric capacity, diode, the type of the voltage regulator
Number it is MC1723, the model TIP122 of second triode;
The voltage regulator first, the 8th, second, third, the nine, the 14th pins difference it is hanging, the 11st pin with
12nd pin is connected and with being digitally connected, and the 5th pin is connected with the 6th pin, the 7th pin and first triode
Colelctor electrode, the 6th electric capacity one end, the connection of the 4th resistance one end, and negative power signal is exported, the 4th pin and the 7th electric capacity
One end, the 4th resistance other end, the connection of 3rd resistor one end, the tenth three-prong are connected with the 7th electric capacity other end, and the tenth
Pin is connected with the diode cathode;
First transistor base, emitter stage are connected with the diode cathode, the input negative supply respectively;
The 3rd resistor other end, the 6th electric capacity other end are respectively with being digitally connected.
4. low level signal amplification device as claimed in claim 1, it is characterised in that the first order amplifier, second level amplification
Device, the model of third level amplifier are AD797.
5. low level signal amplification device as claimed in claim 1, it is characterised in that the bandpass filter includes first, second
Integrated transporting discharging, the 17th, 18 resistance, the 32nd, 33,34,35,38,39 resistance,
3rd, the 38th, 39,50,51,52,53 electric capacity, the model of first, second integrated transporting discharging
For OP37G;
First, the 8th pin of first integrated transporting discharging is hanging, the second pin and described 50th electric capacity one end, the 34th
Resistance one end connects, and three-prong is adjustable with the 38th resistance end, the 38th resistance fixing end, is digitally connected,
Positive and negative power supply signal of seven, the 4th pins respectively with power supply processing unit output is connected, the 6th pin and the described 3rd
The 14 resistance other ends, the 38th electric capacity one end, the connection of the 51st electric capacity one end;
The 50th electric capacity other end is connected with described 32nd resistance one end, the 38th another fixing end of resistance;
The 32nd resistance other end is used for the signal for receiving the first order amplifier output;
The 38th electric capacity other end is connected with described 17th resistance one end, the 33rd resistance one end;
The 17th resistance other end is with being digitally connected;
The 33rd resistance other end and described 52nd electric capacity one end, the 53rd electric capacity one end, the 39th electricity
Hinder fixing end connection;
First, the 8th pin of second integrated transporting discharging is hanging, the second pin and the 52nd electric capacity other end, the 3rd
15 resistance one end connect, three-prong and the adjustable end of the 39th resistance, another fixing end of the 39th resistance, numeral
Ground connect, the seven, the 4th pins respectively with the power supply processing unit output positive and negative power supply signal be connected, the 6th pin and
The 35th resistance other end, the 39th electric capacity one end, the connection of the 53rd electric capacity other end;
The 39th electric capacity other end is connected with described 18th resistance one end, the 3rd electric capacity one end, and after exporting filtering
Signal;
The 18th resistance other end, the 3rd electric capacity other end are respectively with being digitally connected.
6. low level signal amplification device as claimed in claim 1, it is characterised in that first trapper includes the three, the 4th
Integrated transporting discharging, model OP37G, the 20th, 21,22,23 resistance, the 41st, 42,45 electricity
Hold;
The first, the 8th pin difference of 3rd integrated transporting discharging is hanging, and the seven, the 4th pins are single with power supply processing respectively
The positive and negative power supply signal connection of member output, the second pin are connected with the 6th pin, the 23rd resistance fixing end, and for defeated
The signal gone out after filtering out the first Hz noise, three-prong are connected with the 21st resistance one end, 42 electric capacity one end;
The first, the 8th pin difference of 4th integrated transporting discharging is hanging, and the seven, the 4th pins are single with power supply processing respectively
The positive and negative power supply signal connection of member output, the second pin and the 6th pin, the 45th electric capacity one end, the 22nd resistance one
End connection, three-prong are connected with the 23rd adjustable end of resistance;
Another fixing end of 23rd resistance is with being digitally connected;
The 21st resistance other end is connected with the 45th electric capacity other end, the 20th resistance one end;
The 22nd resistance other end is connected with described 41st electric capacity one end;
The 20th resistance other end is connected with the 41st electric capacity other end, and for receiving the second level amplification
The signal of device output.
7. low level signal amplification device as claimed in claim 1, it is characterised in that second trapper includes the five, the 6th
Integrated transporting discharging, model OP37G, the 24th, 26,27,28 resistance, the 43rd, 44,40
6th, 48 electric capacity;
The first, the 8th pin difference of 5th integrated transporting discharging is hanging, and the seven, the 4th pins are single with power supply processing respectively
The positive and negative power supply signal connection of member output, the second pin are consolidated with the 6th pin, the 48th electric capacity one end, the 24th resistance
Fixed end is connected, and three-prong is connected with the 27th resistance one end, 44 electric capacity one end;
The first, the 8th pin difference of 4th integrated transporting discharging is hanging, and the seven, the 4th pins are single with power supply processing respectively
The positive and negative power supply signal connection of member output, the second pin and the 6th pin, the 46th electric capacity one end, the 28th resistance one
End connection, three-prong are connected with the 24th adjustable end of resistance;
Another fixing end of 24th resistance is with being digitally connected;
The 27th resistance other end is connected with the 46th electric capacity other end, the 26th resistance one end;
The 28th resistance other end is connected with described 43rd electric capacity one end;
The 26th resistance other end is connected with the 43rd electric capacity other end, and for receiving first trap
The signal of device output;
The 48th electric capacity other end, which is used to export, filters out the signal after the second Hz noise.
8. low level signal amplification device as claimed in claim 4, it is characterised in that the third level amplifier also includes the tenth
3rd, 14,16,31,36,37,15,26,27 resistance, the 37th, 48,40
9th, 40 electric capacity, the 3rd emitter follower model AD797;
The first pin, the 5th pin, the 8th pin of the third level amplifier are hanging, the 7th pin, the 4th pin respectively with
The positive and negative power supply signal connection of the power supply processing unit output, the second pin and described 13rd resistance one end, the 31st
Resistance one end connects, and three-prong is connected with described 14th resistance one end, the 6th pin and described 37th electric capacity one end,
The 31st resistance other end connects;
The first pin, the 5th pin, the 8th pin of 3rd emitter follower are hanging, the 7th pin, the 4th pin respectively with institute
State the positive and negative power supply signal connection of power supply processing unit output, the second pin and described 37th resistance one end, the 49th
Electric capacity one end is connected, and three-prong is connected with described 36th resistance one end, the 48th electric capacity one end, the 6th pin and institute
State the 40th electric capacity one end, the 37th resistance other end, the connection of the 49th electric capacity other end;
The 13rd resistance other end is with being digitally connected;
The 14th resistance other end is used for the signal for receiving the second trapper output;
The 37th electric capacity other end is connected with the 36th resistance other end, the 16th resistance one end;
The 16th resistance other end, the 48th electric capacity other end are respectively with being digitally connected;
The 40th electric capacity other end and described 15th resistance one end, the 26th resistance one end, the 27th resistance one
End connection, and export the amplified signal;
The 15th resistance other end, the 26th resistance other end, the 27th resistance other end are respectively with digitally connecting
Connect.
9. low level signal amplification device as claimed in claim 1, it is characterised in that the gain of the first order amplifier is
20dB, the gain of the second level amplifier is 35dB, and the gain of the third level amplifier is 20dB.
10. the low level signal amplification device as described in any one of claim 2,3,5,6~8, it is characterised in that the electric capacity is selected
Styrene, silvered mica capacitor, NP0 ceramic electricals perhaps tantalum electric capacity, the resistance select metalfilmresistor.
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Cited By (1)
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---|---|---|---|---|
CN108896469A (en) * | 2018-04-20 | 2018-11-27 | 浙江大学 | A kind of signal acquisition circuit of Grain Loss Sensor |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101433461A (en) * | 2008-12-04 | 2009-05-20 | 上海大学 | Detection circuit for high-performance brain electrical signal of brain-machine interface |
CN104393867A (en) * | 2014-12-10 | 2015-03-04 | 成都英力拓信息技术有限公司 | Output switch voltage stabilizing circuit for computer USB3.0 interface |
CN205510002U (en) * | 2016-03-08 | 2016-08-24 | 西安理工大学 | Amplification and filtering circuit of special signal of telecommunication |
CN206074741U (en) * | 2016-09-29 | 2017-04-05 | 南京信息职业技术学院 | Detection circuit for grounding grid defect diagnosis |
-
2017
- 2017-09-06 CN CN201710794677.0A patent/CN107612513A/en active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101433461A (en) * | 2008-12-04 | 2009-05-20 | 上海大学 | Detection circuit for high-performance brain electrical signal of brain-machine interface |
CN104393867A (en) * | 2014-12-10 | 2015-03-04 | 成都英力拓信息技术有限公司 | Output switch voltage stabilizing circuit for computer USB3.0 interface |
CN205510002U (en) * | 2016-03-08 | 2016-08-24 | 西安理工大学 | Amplification and filtering circuit of special signal of telecommunication |
CN206074741U (en) * | 2016-09-29 | 2017-04-05 | 南京信息职业技术学院 | Detection circuit for grounding grid defect diagnosis |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108896469A (en) * | 2018-04-20 | 2018-11-27 | 浙江大学 | A kind of signal acquisition circuit of Grain Loss Sensor |
CN108896469B (en) * | 2018-04-20 | 2021-04-27 | 浙江大学 | Grain loss sensor's signal acquisition circuit |
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