CN108055018A - The filter circuit of digital signal - Google Patents
The filter circuit of digital signal Download PDFInfo
- Publication number
- CN108055018A CN108055018A CN201711215680.9A CN201711215680A CN108055018A CN 108055018 A CN108055018 A CN 108055018A CN 201711215680 A CN201711215680 A CN 201711215680A CN 108055018 A CN108055018 A CN 108055018A
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- operational amplifier
- resistance
- output terminal
- circuit
- capacitance
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H11/00—Networks using active elements
- H03H11/46—One-port networks
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/66—Digital/analogue converters
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- Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Networks Using Active Elements (AREA)
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Abstract
The present invention provides a kind of circuit design novelty, the filter circuit for the digital signal that multistep treatment can be carried out to digital signal, it includes digital analog converter；Voltage follower circuit is further included, is connected on the analog signal output of digital analog converter；Amplifying circuit is further included, is connected on the output terminal of voltage follower circuit；Further include the low-pass filter circuit being sequentially connected in series, high-pass filtering circuit, bandwidth-limited circuit；Low-pass filter circuit, high-pass filtering circuit, the bandwidth-limited circuit being connected in series form filter circuit；The input terminal of the low-pass filter circuit and the output terminal of amplifying circuit connect；Analog-digital converter is further included, is connected on the output terminal of high-pass filtering circuit.
Description
Technical field
The present invention relates to a kind of circuit more particularly to a kind of filter circuits of digital signal.
Background technology
It is that discrete, dependent variable is also discrete signal that digital signal, which refers to independent variable, digital signal in transmission process not
Only there is higher anti-interference, can also occupy less bandwidth by compression, realize and transmitted more in identical bandwidth
The effect of the digital signals such as more, more high audio, video；It is done to reduce external interference and hardware device to what digital signal was brought
It disturbs, needs to carry out the processing such as power amplification, filtering to digital signal in the transmission of digital signal, in the prior art, in order to right
The filtering of digital signal, common way is realized using two methods of digital signal processor and software processing, in reality
It is relatively simple but more single to the processing mode of digital signal in existing, therefore, it is necessary to design a kind of new number letter
Number process circuit.
The content of the invention
It is an object of the invention to overcome the deficiencies in the prior art, adapt to real needs, provide a kind of circuit design novelty,
The filter circuit of the digital signal of multistep treatment can be carried out to digital signal.
In order to achieve the object of the present invention, the technical solution adopted in the present invention is：
A kind of filter circuit of digital signal is designed, it includes digital analog converter；
Voltage follower circuit is further included, is connected on the analog signal output of digital analog converter；
Amplifying circuit is further included, is connected on the output terminal of voltage follower circuit；
Further include the low-pass filter circuit being sequentially connected in series, high-pass filtering circuit, bandwidth-limited circuit；The low pass being connected in series
Filter circuit, high-pass filtering circuit, bandwidth-limited circuit form filter circuit.
Preferably, the output terminal of the input terminal of the low-pass filter circuit and amplifying circuit connects；
Analog-digital converter is further included, is connected on the output terminal of high-pass filtering circuit.
Preferably, the voltage follower circuit includes operational amplifier A 1, and the in-phase input end of operational amplifier A 1 is electricity
Pressure follows the input terminal of circuit, and the output terminal of operational amplifier A 1 is the output terminal of voltage follower circuit, the operational amplifier
The reverse input end of A1 is also connected with the output terminal of the operational amplifier A 1.
Preferably, the amplifying circuit includes the first amplifying circuit, the second amplifying circuit that are connected in series.
Preferably, first amplifying circuit includes operational amplifier A 2, connects on the inverting input of operational amplifier A 2
Be connected to resistance R1 and for the first amplifying circuit input terminal；The in-phase input end ground connection of operational amplifier A 2；The operation amplifier
The reverse input end of device A2 is connected by output terminals of the capacitance C1 also with the operational amplifier A 2, the operational amplifier A 2
Output terminal is the output terminal of the first amplifying circuit.
Preferably, second amplifying circuit includes operational amplifier A 3, and the inverting input of operational amplifier A 3 passes through
Resistance R2 is connected with the output terminal of operational amplifier A 2；The in-phase input end ground connection of operational amplifier A 3；The operational amplifier
The reverse input end of A3 is connected by output terminals of the resistance R3 also with the operational amplifier A 3, the operational amplifier A 3 it is defeated
Outlet is the output terminal of the second amplifying circuit.
Preferably, the resistance R3 is variable resistor.
Preferably, the low-pass filter circuit includes operational amplifier A 4, the noninverting input of the operational amplifier A 4
On be sequentially connected that there are two the input terminal of the resistance R5 being connected in series, resistance R4, the resistance R4 are defeated for low-pass filter circuit
Enter to hold and be connected with the output terminal of the operational amplifier A 3.
Preferably, it is connected between the resistance R5 and resistance R4 by a capacitance C2 with the output terminal of operational amplifier A 4；
It is grounded between the noninverting input of the operational amplifier A 4 and resistance R5 by capacitance C3；
Preferably, two resistance R6 being connected in series, resistance R7, the input end grounding of the resistance R6, the resistance are further included
Output terminal of the output terminal of R7 also with operational amplifier A 4 is connected；The reverse input end of the operational amplifier A 4 is connected to resistance
Between R6 and resistance R7.
Preferably, the output terminal of the operational amplifier A 4 is the output terminal of the low-pass filter circuit.
Preferably, the high-pass filtering circuit includes operational amplifier A 5, and the output terminal of the operational amplifier A 5 is should
The output terminal of high-pass filtering circuit.
Preferably, two the capacitance C4 being connected in series, capacitance C5 are further included, the input terminal of capacitance C4 is high-pass filtering electricity
The input terminal on road is simultaneously connected with the output terminal of operational amplifier A 4, capacitance C5 output terminals and the reverse input end of operational amplifier A 5
Connection.
Preferably, it is grounded between the capacitance C4 and capacitance C5 by resistance R8, it is also logical between the appearance C4 and capacitance C5
The output terminal that capacitance C6 is crossed with the operational amplifier A 5 is connected；The capacitance C5 and the reverse input end of operational amplifier A 5 pass through
Resistance R10 is connected with the output terminal of the operational amplifier A 5.
Preferably, the noninverting input of the operational amplifier A 5 is grounded by resistance R9.
Preferably, the bandpass filter includes operational amplifier A 6, and the output terminal of the operational amplifier A 6 is the height
The output terminal of bandpass filter circuit is simultaneously connected with the input terminal of the analog-digital converter.
Preferably, the resistance R11 being connected in series, capacitance C8, the output terminal and operational amplifier of the capacitance C8 are further included
A6 reverse input ends connect；The input terminal of the resistance R11 for the bandpass filter input terminal and with operational amplifier A 5
Output terminal connects.
Preferably, it is grounded between the resistance R11 and capacitance C8 by resistance R12, between the resistance R11 and capacitance C8
Also it is connected by capacitance C7 with the output terminal of operational amplifier A 6；The reverse input end of the capacitance C8 and operational amplifier A 6 it
Between the output terminal of operational amplifier A 6 is connected to by resistance R13.
Preferably, the in-phase input end of the operational amplifier A 6 is grounded by capacitance C9.
Preferably, two resistance being connected in series 14, resistance 15 are further included, the input terminal of the resistance 14 and a power supply connect
It connects, the output head grounding of the resistance 15, connection and resistance between the capacitance C9 and the in-phase input end of operational amplifier A 6
Between 14 and resistance 15.
Preferably, the location swap of the low-pass filter circuit, high-pass filtering circuit.
The beneficial effects of the present invention are：
It is novel in design for this circuit, is easier to realize, more by that can be carried out after the digital-to-analogue conversion to digital signal to it in implementation
Grade filtering process, can then be exported by analog-digital converter, can carry out multistep treatment to digital signal in this way.
Description of the drawings
Fig. 1 is the schematic block circuit diagram of the present invention；
Fig. 2 is the voltage follower circuit principle schematic in the present invention；
Fig. 3 is the amplifying circuit principle schematic in the present invention；
Fig. 4 is the low-pass filter circuit principle schematic in the present invention；
Fig. 5 is the high-pass filtering circuit principle schematic in the present invention；
Fig. 6 is the bandwidth-limited circuit principle schematic in the present invention.
Specific embodiment
The present invention is further described with reference to the accompanying drawings and examples：
Embodiment 1：A kind of filter circuit of digital signal, referring to Fig. 1 to Fig. 6.
It includes digital analog converter to this circuit, for converting digital signals into analog signal.
Voltage follower circuit is further included, is connected on the analog signal output of digital analog converter, for analog signal
It is nursed one's health.
Amplifying circuit is further included, for carrying out power amplification to the analog signal exported through voltage follower circuit and being connected to
On the output terminal of voltage follower circuit.
Further include the low-pass filter circuit being sequentially connected in series, high-pass filtering circuit, bandwidth-limited circuit；It is connected in series
Low-pass filter circuit, high-pass filtering circuit, bandwidth-limited circuit form filter circuit, pass through this three low-pass filter circuits, height
Bandpass filter circuit, bandwidth-limited circuit carry out three-level filtering processing；The input terminal of low-pass filter circuit described above and amplification electricity
The output terminal connection on road.
Analog-digital converter is further included, for converting analog signals into digital signal, is connected to the defeated of high-pass filtering circuit
In outlet.
Specifically, the voltage follower circuit includes operational amplifier A 1, the in-phase input end of operational amplifier A 1 is
The input terminal of voltage follower circuit is simultaneously connected with the output terminal of digital analog converter, and the output terminal of operational amplifier A 1 is voltage follow
The output terminal of circuit, the reverse input end of the operational amplifier A 1 are also connected with the output terminal of the operational amplifier A 1.
Specifically, the amplifying circuit includes the first amplifying circuit, the second amplifying circuit that are connected in series.
It includes operational amplifier A 2 with first amplifying circuit, is connected on the inverting input of operational amplifier A 2
Resistance R1 and for the first amplifying circuit input terminal and be connected with the output terminal of operational amplifier A 1；The same phase of operational amplifier A 2
Input end grounding；The reverse input end of the operational amplifier A 2 passes through output terminals of the capacitance C1 also with the operational amplifier A 2
Connection, the output terminal of the operational amplifier A 2 are the output terminal of the first amplifying circuit.
Second amplifying circuit includes operational amplifier A 3, the inverting input of operational amplifier A 3 by resistance R2 with
The output terminal connection of operational amplifier A 2；The in-phase input end ground connection of operational amplifier A 3；The operational amplifier A 3 it is reversed
Input terminal is connected by output terminals of the resistance R3 also with the operational amplifier A 3, and the output terminal of the operational amplifier A 3 is the
The output terminal of two amplifying circuits.
Preferably, the resistance R3 is variable resistor, can change putting for amplifying circuit by the resistance value for changing resistance R3
Big multiple.
Specifically, the low-pass filter circuit includes operational amplifier A 4, the noninverting input of the operational amplifier A 4
On be sequentially connected that there are two the input terminal of the resistance R5 being connected in series, resistance R4, the resistance R4 are defeated for low-pass filter circuit
Enter to hold and be connected with the output terminal of the operational amplifier A 3.
It is connected between the resistance R5 and resistance R4 by a capacitance C2 with the output terminal of operational amplifier A 4；The computing
It is grounded between the noninverting input of amplifier A4 and resistance R5 by capacitance C3.Further include two resistance R6, the electricity being connected in series
R7, the input end grounding of the resistance R6 are hindered, the output terminal of the output terminal of the resistance R7 also with operational amplifier A 4 is connected；Institute
The reverse input end for stating operational amplifier A 4 is connected between resistance R6 and resistance R7.
The output terminal of the operational amplifier A 4 is the output terminal of the low-pass filter circuit.
Specifically, the high-pass filtering circuit includes operational amplifier A 5, the output terminal of the operational amplifier A 5 is should
The output terminal of high-pass filtering circuit.
Two the capacitance C4 being connected in series, capacitance C5 are further included, the input terminal of capacitance C4 is the defeated of the high-pass filtering circuit
Enter to hold and be connected with the output terminal of operational amplifier A 4, capacitance C5 output terminals are connected with the reverse input end of operational amplifier A 5.
It is grounded between the capacitance C4 and capacitance C5 by resistance R8, also passes through capacitance C6 between the appearance C4 and capacitance C5
It is connected with the output terminal of the operational amplifier A 5；The capacitance C5 and the reverse input end of operational amplifier A 5 pass through resistance R10
It is connected with the output terminal of the operational amplifier A 5.
Preferably, the noninverting input of the operational amplifier A 5 is grounded by resistance R9.
Specifically, the bandpass filter includes operational amplifier A 6, the output terminal of the operational amplifier A 6 is the height
The output terminal of bandpass filter circuit is simultaneously connected with the input terminal of the analog-digital converter.
It is reversely defeated to further include the resistance R11 being connected in series, the output terminal of capacitance C8, the capacitance C8 and operational amplifier A 6
Enter end connection；The input terminal of the resistance R11 is the input terminal of the bandpass filter and connects with the output terminal of operational amplifier A 5
It connects.
It is grounded by resistance R12 between the resistance R11 and capacitance C8, also passed through between the resistance R11 and capacitance C8
Capacitance C7 is connected with the output terminal of operational amplifier A 6；Pass through between the capacitance C8 and the reverse input end of operational amplifier A 6
Resistance R13 is connected to the output terminal of operational amplifier A 6.
Preferably, the in-phase input end of the operational amplifier A 6 is grounded by capacitance C9.
Two resistance being connected in series 14, resistance 15 are further included, the input terminal of the resistance 14 is connected with a power supply, described
The output head grounding of resistance 15, connection and resistance 14 and resistance between the capacitance C9 and the in-phase input end of operational amplifier A 6
Between 15.
In this circuit, the low-pass filter circuit, the position of high-pass filtering circuit are interchangeable.
This circuit is in use, passes through digital analog converter（D/A）Digital-to-analogue conversion is carried out to digital signal, purchases by group voltage afterwards
Circuit is followed to be nursed one's health, is then amplified by amplifying circuit in the three-level filtering circuit of rear end and carries out three-level filtering,
It is exported finally by digital signal is again converted to after analog-to-digital conversion, digital signal can so be handled.
What the embodiment of the present invention was announced is preferred embodiment, but is not limited thereto, the ordinary skill people of this field
Member easily according to above-described embodiment, understands the spirit of the present invention, and makes different amplification and variation, but as long as not departing from this
The spirit of invention, all within the scope of the present invention.
Claims (9)
1. a kind of filter circuit of digital signal, it is characterised in that：It includes：
Digital analog converter；
Voltage follower circuit is connected on the analog signal output of digital analog converter；
Amplifying circuit is connected on the output terminal of voltage follower circuit；
Low-pass filter circuit, high-pass filtering circuit, the bandwidth-limited circuit being sequentially connected in series；The low-pass filtering electricity being connected in series
Road, high-pass filtering circuit, bandwidth-limited circuit form filter circuit；
The input terminal of the low-pass filter circuit and the output terminal of amplifying circuit connect；
Analog-digital converter is connected on the output terminal of high-pass filtering circuit.
2. the filter circuit of digital signal as described in claim 1, it is characterised in that：The voltage follower circuit includes computing
Amplifier A1, the in-phase input end of operational amplifier A 1 are the input terminal of voltage follower circuit, the output terminal of operational amplifier A 1
For the output terminal of voltage follower circuit, the reverse input end of the operational amplifier A 1 is also connected with the output of the operational amplifier A 1
End.
3. the filter circuit of digital signal as claimed in claim 2, it is characterised in that：The amplifying circuit includes being connected in series
The first amplifying circuit, the second amplifying circuit.
4. the filter circuit of digital signal as claimed in claim 3, it is characterised in that：First amplifying circuit includes computing
Amplifier A2 is connected with resistance R1 on the inverting input of operational amplifier A 2 and for the input terminal of the first amplifying circuit；Computing
The in-phase input end ground connection of amplifier A2；The reverse input end of the operational amplifier A 2 is also put by a capacitance C1 with the computing
The output terminal connection of big device A2, the output terminal of the operational amplifier A 2 are the output terminal of the first amplifying circuit；
Second amplifying circuit includes operational amplifier A 3, and the inverting input of operational amplifier A 3 passes through resistance R2 and computing
The output terminal connection of amplifier A2；The in-phase input end ground connection of operational amplifier A 3；The reversed input of the operational amplifier A 3
End is connected by output terminals of the resistance R3 also with the operational amplifier A 3, and the output terminal of the operational amplifier A 3 is put for second
The output terminal of big circuit.
5. the filter circuit of digital signal as claimed in claim 4, it is characterised in that：The resistance R3 is variable resistor.
6. the filter circuit of digital signal as claimed in claim 5, it is characterised in that：The low-pass filter circuit includes computing
Amplifier A4 is sequentially connected in the noninverting input of the operational amplifier A 4 there are two resistance R5, the resistance R4 being connected in series,
The input terminal of the resistance R4 is the input terminal of low-pass filter circuit and is connected with the output terminal of the operational amplifier A 3；
It is connected between the resistance R5 and resistance R4 by a capacitance C2 with the output terminal of operational amplifier A 4；The operation amplifier
It is grounded between the noninverting input of device A4 and resistance R5 by capacitance C3；
Further include two resistance R6 being connected in series, resistance R7, the input end grounding of the resistance R6, the output of the resistance R7
The output terminal also with operational amplifier A 4 is held to be connected；The reverse input end of the operational amplifier A 4 is connected to resistance R6 and resistance
Between R7；
The output terminal of the operational amplifier A 4 is the output terminal of the low-pass filter circuit.
7. the filter circuit of digital signal as claimed in claim 6, it is characterised in that：The high-pass filtering circuit includes computing
Amplifier A5, the output terminal of the operational amplifier A 5 are the output terminal of the high-pass filtering circuit；
Two the capacitance C4 being connected in series, capacitance C5 are further included, the input terminal of capacitance C4 is the input terminal of the high-pass filtering circuit
And be connected with the output terminal of operational amplifier A 4, capacitance C5 output terminals are connected with the reverse input end of operational amplifier A 5；
It is grounded between the capacitance C4 and capacitance C5 by resistance R8, also by capacitance C6 with being somebody's turn to do between the appearance C4 and capacitance C5
The output terminal connection of operational amplifier A 5；The capacitance C5 and the reverse input end of operational amplifier A 5 by resistance R10 and are somebody's turn to do
The output terminal connection of operational amplifier A 5；
The noninverting input of the operational amplifier A 5 is grounded by resistance R9.
8. the filter circuit of digital signal as claimed in claim 7, it is characterised in that：The bandpass filter is put including computing
Big device A6, the output terminal of the operational amplifier A 6 are the output terminal of the high-pass filtering circuit and defeated with the analog-digital converter
Enter end connection；
Further include output terminal and 6 reverse input end of operational amplifier A of the resistance R11 being connected in series, capacitance C8, the capacitance C8
Connection；The input terminal of the resistance R11 is the input terminal of the bandpass filter and is connected with the output terminal of operational amplifier A 5；
It is grounded between the resistance R11 and capacitance C8 by resistance R12, also passes through capacitance between the resistance R11 and capacitance C8
C7 is connected with the output terminal of operational amplifier A 6；Pass through resistance between the capacitance C8 and the reverse input end of operational amplifier A 6
R13 is connected to the output terminal of operational amplifier A 6；
The in-phase input end of the operational amplifier A 6 is grounded by capacitance C9；
Two resistance being connected in series 14, resistance 15 are further included, the input terminal of the resistance 14 is connected with a power supply, the resistance
15 output head grounding, between the capacitance C9 and the in-phase input end of operational amplifier A 6 connection and resistance 14 and resistance 15 it
Between.
9. the filter circuit of digital signal as described in claim 1, it is characterised in that：The low-pass filter circuit, high pass filter
The location swap of wave circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711215680.9A CN108055018A (en) | 2017-11-28 | 2017-11-28 | The filter circuit of digital signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711215680.9A CN108055018A (en) | 2017-11-28 | 2017-11-28 | The filter circuit of digital signal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108055018A true CN108055018A (en) | 2018-05-18 |
Family
ID=62120846
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711215680.9A Pending CN108055018A (en) | 2017-11-28 | 2017-11-28 | The filter circuit of digital signal |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108055018A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109547027A (en) * | 2018-11-27 | 2019-03-29 | 昂纳信息技术（深圳）有限公司 | A kind of digiverter and a kind of integrated system based on digiverter |
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| CN101451864A (en) * | 2008-12-22 | 2009-06-10 | 合肥工业大学 | Improved low power consumption two-wire system vortex shedding flowmeter |
| CN201821336U (en) * | 2010-09-30 | 2011-05-04 | 中国航天科工集团第三研究院第八三五七研究所 | High-precision analog-digital collection circuit based on negative feedback |
| CN203406831U (en) * | 2013-07-11 | 2014-01-22 | 长沙理工大学 | Amplification circuit with zero correction circuit |
| CN103873022A (en) * | 2012-12-14 | 2014-06-18 | 中国航空工业集团公司航空动力控制系统研究所 | Passive thermal resistor sensor signal simulation circuit |
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2017
- 2017-11-28 CN CN201711215680.9A patent/CN108055018A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101451864A (en) * | 2008-12-22 | 2009-06-10 | 合肥工业大学 | Improved low power consumption two-wire system vortex shedding flowmeter |
| CN201821336U (en) * | 2010-09-30 | 2011-05-04 | 中国航天科工集团第三研究院第八三五七研究所 | High-precision analog-digital collection circuit based on negative feedback |
| CN103873022A (en) * | 2012-12-14 | 2014-06-18 | 中国航空工业集团公司航空动力控制系统研究所 | Passive thermal resistor sensor signal simulation circuit |
| CN203406831U (en) * | 2013-07-11 | 2014-01-22 | 长沙理工大学 | Amplification circuit with zero correction circuit |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109547027A (en) * | 2018-11-27 | 2019-03-29 | 昂纳信息技术（深圳）有限公司 | A kind of digiverter and a kind of integrated system based on digiverter |
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Application publication date: 20180518 |