CN218830531U - Feedback type high and low sound regulating circuit - Google Patents
Feedback type high and low sound regulating circuit Download PDFInfo
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- CN218830531U CN218830531U CN202223267397.XU CN202223267397U CN218830531U CN 218830531 U CN218830531 U CN 218830531U CN 202223267397 U CN202223267397 U CN 202223267397U CN 218830531 U CN218830531 U CN 218830531U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The utility model discloses a feedback type high bass regulating circuit, it is including the gain control circuit that is used for realizing audio input signal amplification, the high bass frequency regulating circuit that is used for adjusting the high bass cut-off frequency of tone circuit and be used for carrying out the feedback amplification to the signal with the feedback amplifier circuit of stable system gain, gain control circuit, high bass frequency regulating circuit, feedback amplifier circuit electric connection in proper order, wherein, the equivalent resistance of high bass frequency regulating circuit is as the input resistance and the feedback amplifier circuit electric connection of feedback amplifier circuit; therefore, accurate control over the high and low sound promotion or attenuation gain range and the frequency regulation range is realized, the signal control stability of the audio system is improved, and the obvious amplitude change of the middle sound signal is avoided during high and low sound regulation, so that the noise of the audio system is smaller, and the harmonic distortion is smaller.
Description
Technical Field
The utility model relates to a technical field of audio frequency regulation control especially relates to a feedback type high bass regulating circuit.
Background
With the development of audio and video electronic technologies, more and more audio and video electronic devices are owned by people, and the requirements of people on the processing of sound by an audio system are higher and higher, wherein noise reduction and accurate control of audio are the key directions of current market research and development. The patent application with the application number of CN201120539114.5 adopts the technical scheme that the noise reduction pickup device comprises a microphone, a preamplifier, a dynamic noise reduction module, a downward expander and an audio isolator, wherein the output end of the microphone is connected with the input end of the preamplifier, the output end of the preamplifier is connected with the input end of the dynamic noise reduction module, the output end of the dynamic noise reduction module is connected with the input end of the downward expander, and the output end of the downward expander is connected with the input end of the audio isolator. Although the scheme provides that the audio signal is amplified through the preamplifier and is subjected to noise reduction through the dynamic noise reduction module, the preamplifier and the dynamic noise reduction module are mutually independent processing modules, and only carry out independent amplification and noise reduction processing on the basis of receiving a signal output by the previous stage of processing, the processing mode is easily interfered, and the intermediate tone signal generates obvious amplitude change during high-low tone adjustment, so that the signal-to-noise ratio and the working stability obtained by processing are poor.
SUMMERY OF THE UTILITY MODEL
In order to overcome the problem that prior art exists, the utility model provides a feedback type high and low sound regulating circuit, it can promote or decay gain range and frequency control scope to high and low sound and realize accurate control, improves audio system's signal control stability, and the well sound signal takes place obvious amplitude variation when avoiding high and low sound to adjust.
In order to solve the technical problem, the utility model discloses a technical scheme is: the gain control circuit, the high-low audio frequency adjusting circuit and the feedback amplifying circuit are electrically connected in sequence, wherein an equivalent resistor of the high-low audio frequency adjusting circuit is used as an input resistor of the feedback amplifying circuit and is electrically connected with the feedback amplifying circuit.
Preferably, the gain control circuit includes a first operational amplifier, an output terminal of the first operational amplifier is connected to an inverting input terminal thereof, and a resistor and a capacitor connected in parallel are disposed between the output terminal and the inverting input terminal of the first operational amplifier.
Preferably, the high-low audio frequency adjusting circuit includes a low-pass filter and a high-pass filter, the low-pass filter and the high-pass filter are connected in parallel, and a blocking capacitor is arranged between the low-pass filter and the high-pass filter.
Preferably, the feedback amplifying circuit includes a second operational amplifier, an output terminal of the second operational amplifier is connected to an inverting input terminal thereof, and an output terminal of the high-low audio frequency adjusting circuit is connected to the inverting input terminal of the second operational amplifier.
Preferably, the high-low audio frequency adjusting circuit comprises a noise eliminating circuit for eliminating noise in audio frequency.
Preferably, the noise cancellation circuit comprises a resistor and a capacitor which are arranged in parallel, and the resistor and the capacitor which are connected in parallel are connected between the output end and the inverting input end of the second operational amplifier.
Preferably, the gain control circuit includes a first operational amplifier U6, a resistor R29, and a capacitor C42, the inverting input terminal of the first operational amplifier U6 is connected to the signal output terminal of the audio input circuit, the forward input terminal is grounded, and the output terminal thereof is connected to the inverting input terminal, the resistor R29 and the capacitor C42 are arranged in parallel, one parallel terminal thereof is connected to the inverting input terminal of the first operational amplifier U6, and the other parallel terminal thereof is connected to the output terminal of the first operational amplifier U6.
Preferably, the high-low audio frequency adjusting circuit includes potentiometers W1 and W2, resistors R9, R10, R11, R15 and R16, and capacitors C4, C5 and C6, wherein the potentiometer W1, the resistors R9, R10 and R16, and the capacitors C5 and C6 constitute a low-pass filter, the potentiometer W2, the resistors R11 and R15, and the capacitor C4 constitute a high-pass filter, the resistor R9 is sequentially connected in series with the potentiometer W1 and the resistor R10, a sliding end of the potentiometer W1 is connected to a signal input end of the feedback amplifying circuit through the resistor R16, one end of the capacitor C5 is connected between the resistor R9 and the potentiometer W1, the other end of the capacitor C6 is connected between the potentiometer W1 and the resistor R16, one end of the capacitor C6 is connected between the resistor R10 and the potentiometer W1, and the other end of the capacitor W1 is connected between the potentiometer W16 and the resistor R16; the resistor R11 is sequentially connected with the potentiometer W2 and the resistor R15 in series, and the sliding end of the potentiometer W2 is connected to the signal input end of the feedback amplifying circuit through the capacitor C4.
Preferably, the feedback amplifying circuit comprises a second operational amplifier U5, resistors R18 and R19, the inverting input terminal of the second operational amplifier U5 is connected to the signal output terminal of the high-low audio frequency adjusting circuit, the forward input terminal is grounded, the output terminal of the second operational amplifier U5 is connected to the signal input terminal of the audio output circuit, meanwhile, the output terminal of the second operational amplifier U5 is sequentially connected in series with the resistors R18 and R19 and is grounded, and one end of the resistor R18 connected in series with the resistor R19 is connected to the inverting input terminal of the second operational amplifier U5.
Preferably, the noise cancellation circuit includes a capacitor C7 and a resistor R17, the capacitor C7 is disposed on a feedback line of the feedback amplification circuit, one end of the capacitor C7 is connected between the resistors R18 and R19, the other end of the capacitor C7 is connected to the inverting input terminal of the second operational amplifier U5, one end of the resistor R17 is connected to the inverting input terminal of the second operational amplifier U5, and the other end of the resistor R17 is grounded.
The utility model discloses a gain control circuit realizes that audio input signal enlargies, adjust the high bass cut-off frequency of tone circuit through high bass frequency regulating circuit, carry out negative feedback through feedback amplifier circuit to the signal and enlarge with the stable system gain, and regard high bass frequency regulating circuit's equivalent resistance as feedback amplifier circuit's input resistance and feedback amplifier circuit electric connection, thereby promote or decay gain range and frequency control scope to high bass and realize accurate control, improve audio system's signal control stability, well sound signal takes place obvious range change when avoiding high bass to adjust, make the audio system noise littleer, harmonic distortion is littleer.
Drawings
Fig. 1 is an overall circuit schematic diagram of a feedback type bass/bass adjusting circuit according to an embodiment of the present invention.
Fig. 2 is a schematic circuit diagram of a gain control circuit in the feedback type bass/bass adjusting circuit according to an embodiment of the present invention.
Fig. 3 is a schematic circuit diagram of a bass frequency adjusting circuit in the feedback type bass adjusting circuit according to an embodiment of the present invention.
Fig. 4 is a schematic circuit diagram of a noise cancellation circuit in the feedback type bass/bass tuning circuit according to an embodiment of the present invention.
Fig. 5 is a schematic circuit diagram of a feedback amplifying circuit in the feedback bass/bass adjusting circuit according to the embodiment of the present invention.
The components in the drawings are numbered as follows:
1. a gain control circuit; 2. a high-low audio frequency adjustment circuit; 3. a feedback amplification circuit; 4. a noise cancellation circuit.
Detailed Description
The following detailed description of the preferred embodiments of the present invention will be provided in conjunction with the accompanying drawings, so as to enable those skilled in the art to more easily understand the advantages and features of the present invention, and thereby define the scope of the invention more clearly and clearly.
The embodiment of the utility model provides a feedback type high bass regulating circuit, as shown in fig. 1, it is including the gain control circuit 1 that is used for realizing audio input signal amplification, a high bass frequency regulating circuit 2 that is used for adjusting the high bass cut-off frequency of tone circuit, and be used for carrying out the feedback amplification to the signal with the feedback amplifier circuit 3 of stable system gain, gain control circuit 1, high bass frequency regulating circuit 2, feedback amplifier circuit 3 electric connection in proper order, the signal input termination of gain control circuit 1 is the signal output part of audio input circuit, the signal output termination of feedback amplifier circuit 3 is the signal input part of audio output circuit; the equivalent resistance of the high-low audio frequency adjusting circuit 2 is used as the input resistance of the feedback amplifying circuit 3 and is electrically connected with the feedback amplifying circuit 3, so that accurate control is realized on the high-low sound promotion or attenuation gain range and the frequency adjusting range, and the signal control stability of the audio system is improved.
The gain control circuit 1 comprises a first operational amplifier, an output end of the first operational amplifier is connected with an inverting input end of the first operational amplifier, and a resistor and a capacitor which are arranged in parallel are arranged between the output end and the inverting input end of the first operational amplifier. As shown in fig. 2, the gain control circuit 1 includes a first operational amplifier U6, a resistor R29, and a capacitor C42, wherein a reverse input terminal of the first operational amplifier U6 is connected to a signal output terminal of the audio input circuit, a forward input terminal is grounded, and an output terminal thereof is connected to the reverse input terminal, the resistor R29 and the capacitor C42 are connected in parallel, a parallel terminal thereof is connected to the reverse input terminal of the first operational amplifier U6, and another parallel terminal thereof is connected to the output terminal of the first operational amplifier U6, thereby implementing uniform control on different audio signal amplitudes, and preventing overload or output decrease caused by input of a certain audio source.
A polar capacitor C17 is arranged between the gain control circuit 1 and the high-low audio frequency adjusting circuit 2.
The high-low audio frequency adjusting circuit 2 comprises a low-pass filter and a high-pass filter, the low-pass filter and the high-pass filter are arranged in parallel, and a blocking capacitor is arranged between the low-pass filter and the high-pass filter. Specifically, as shown in fig. 3, the high-low audio frequency adjusting circuit 2 includes potentiometers W1 and W2, resistors R9, R10, R11, R15 and R16, and capacitors C4, C5 and C6; the resistor R9 is sequentially connected with the potentiometer W1 and the resistor R10 in series, the sliding end of the potentiometer W1 is connected with the reverse input end of a second operational amplifier of the feedback amplifying circuit 3 through the resistor R16, one end of the capacitor C5 is connected between the resistor R9 and the potentiometer W1, the other end of the capacitor C5 is connected between the potentiometer W1 and the resistor R16, one end of the capacitor C6 is connected between the resistor R10 and the potentiometer W1, and the other end of the capacitor C6 is connected between the potentiometer W1 and the resistor R16; the resistor R11 is sequentially connected with the potentiometer W2 and the resistor R15 in series, and the sliding end of the potentiometer W2 is connected with the reverse input end of a second operational amplifier in the feedback amplifying circuit 3 through a capacitor C4.
The potentiometer W1 is used as a bass adjusting potentiometer, and the capacitors C5 and C6 and the resistor R16 are used as low-pass filters; when the sliding end of the potentiometer W1 moves to the leftmost end, the bass lift amount is the largest, the audio signal is directly connected to the reverse input end of the second operational amplifier in the feedback amplifying circuit 3 through the capacitor C17 and the resistor R16 to realize negative feedback amplification, the capacities of the capacitors C5 and C6 are small enough, the high-frequency signal cannot pass through, and the capacitor C4 is regarded as an open circuit.
When the sliding end of the potentiometer W1 moves to the rightmost end, the bass attenuation amount is the largest, audio signals sequentially pass through the capacitor C17, the resistor R9, the potentiometer W1 and the resistor R16 and are connected to the reverse input end of the second operational amplifier in the feedback amplifying circuit 3 to realize negative feedback amplification, the capacities of the capacitors C5 and C6 are small enough, high-frequency signals cannot pass through the capacitors, and the capacitor C4 is regarded as an open circuit.
The potentiometer W2 is used as a high-pitch potentiometer, and the resistors R11 and R15 and the capacitor C4 are used as high-pass filters; when the sliding end of the potentiometer W2 moves to the leftmost end, the high-pitch lift is the largest, the audio signal is directly connected to the reverse input end of the second operational amplifier in the feedback amplifying circuit 3 through the resistor R11 and the capacitor C4 in sequence to realize negative feedback amplification, the capacity of the capacitor C4 is small enough, the low-frequency signal cannot pass through, and the capacitors C5 and C6 can be regarded as short circuits.
When the sliding end of the potentiometer W2 moves to the rightmost end, the high-pitch attenuation amount is the largest, the audio signal is connected to the reverse input end of the second operational amplifier in the feedback amplifying circuit 3 through the resistor R11, the potentiometer W2 and the capacitor C4 in sequence to realize negative feedback amplification, the capacity of the capacitor C4 is small enough, the low-frequency signal cannot pass through, and the capacitors C5 and C6 can be regarded as short circuits.
The feedback amplifying circuit 3 comprises a second operational amplifier, the output end of the second operational amplifier is connected with the inverting input end of the second operational amplifier, and the output end of the high-low audio frequency adjusting circuit 2 is connected with the inverting input end of the second operational amplifier. As shown in fig. 4, the feedback amplifying circuit 3 includes a second operational amplifier U5, resistors R18 and R19, an inverting input terminal of the second operational amplifier U5 is connected to the signal output terminal of the high-low audio frequency adjusting circuit 2, a forward input terminal is grounded, an output terminal of the second operational amplifier U5 is connected to the signal input terminal of the audio output circuit, meanwhile, an output terminal of the second operational amplifier U5 is sequentially connected in series with the resistors R18 and R19 and is grounded, and one end of the resistor R18 connected in series with the resistor R19 is connected to the inverting input terminal of the second operational amplifier U5.
The equivalent resistance of the high-low audio frequency adjusting circuit 2 is used as the input resistance of the feedback amplifying circuit 3, the capacitor C7 is connected with the R18 in parallel and is used as a feedback network to control the negative feedback quantity, and the self-oscillation of the system caused by overlarge gain is prevented; the resistor R18 and the resistor R19 are used as voltage dividing resistors, and the values of the resistors control the open loop gain of the whole audio system, so that the amplification factor of an audio circuit and the open loop gain of the audio system are controlled, self-oscillation of the system caused by overlarge gain is prevented, noise is reduced, and the signal-to-noise ratio is improved.
It is further preferable that the high-low audio frequency adjusting circuit 2 includes a noise eliminating circuit 4 for eliminating noise in audio frequency, and the noise eliminating circuit 4 includes a resistor and a capacitor arranged in parallel, and the resistor and the capacitor connected in parallel are connected between the output end and the inverting input end of the second operational amplifier. As shown in fig. 5, the noise cancellation circuit 4 includes a capacitor C7 and a resistor R17, the capacitor C7 is disposed on the feedback line of the feedback amplification circuit 3, one end of the capacitor C7 is connected between the resistors R18 and R19, the other end is connected to the inverting input terminal of the second operational amplifier U5, one end of the resistor R17 is connected to the inverting input terminal of the second operational amplifier U5, and the other end is grounded.
The utility model discloses feedback formula high bass regulating circuit, it realizes audio input signal through gain control circuit 1 and enlargies, adjust the high bass cut-off frequency of tone circuit through high bass frequency regulating circuit 2, carry out negative feedback amplification with the stable system gain to the signal through feedback amplifier circuit 3, and regard the equivalent resistance of high bass frequency regulating circuit 2 as feedback amplifier circuit 3's input resistance and feedback amplifier circuit 3 electric connection, thereby promote or decay gain range and frequency control scope to high bass and realize accurate control, improve audio system's signal control stability, well audio signal takes place obvious range variation when avoiding high bass to adjust, make the audio system noise littleer, harmonic distortion is littleer.
The above is only the embodiment of the present invention, not limiting the scope of the present invention, all the equivalent structures or equivalent processes of the present invention are used in the specification and the attached drawings, or directly or indirectly applied to other related technical fields, and all the same principles are included in the protection scope of the present invention.
Claims (10)
1. The feedback type high-low frequency adjusting circuit is characterized by comprising a gain control circuit for amplifying an audio input signal, a high-low frequency adjusting circuit for adjusting the cut-off frequency of high-low frequency of a tone circuit and a feedback amplifying circuit for carrying out negative feedback amplification on a signal to stabilize the gain of a system, wherein the gain control circuit, the high-low frequency adjusting circuit and the feedback amplifying circuit are electrically connected in sequence, and the equivalent resistance of the high-low frequency adjusting circuit is used as the input resistance of the feedback amplifying circuit and is electrically connected with the feedback amplifying circuit.
2. The feedback bass tone tuning circuit of claim 1, wherein the gain control circuit comprises a first operational amplifier, an output terminal of the first operational amplifier is connected to an inverting input terminal of the first operational amplifier, and a resistor and a capacitor are disposed in parallel between the output terminal and the inverting input terminal of the first operational amplifier.
3. The feedback bass/bass tuning circuit of claim 1, wherein the bass/bass frequency tuning circuit comprises a low pass filter and a high pass filter, the low pass filter and the high pass filter are arranged in parallel, and a blocking capacitor is arranged between the low pass filter and the high pass filter.
4. The feedback bass/audio frequency adjusting circuit of claim 1, wherein the feedback amplifying circuit comprises a second operational amplifier, an output terminal of the second operational amplifier is connected to an inverting input terminal thereof, and an output terminal of the bass/audio frequency adjusting circuit is connected to an inverting input terminal of the second operational amplifier.
5. The feedback bass/bass tuning circuit of claim 1, wherein the bass/bass frequency tuning circuit comprises a noise cancellation circuit for canceling noise in the audio frequency.
6. The feedback bass tuning circuit of claim 5, wherein the noise cancellation circuit comprises a resistor and a capacitor arranged in parallel, the parallel resistor and capacitor being connected between the output and the inverting input of the second operational amplifier.
7. The feedback type bass adjusting circuit of claim 2, wherein the gain control circuit comprises a first operational amplifier U6, a resistor R29, and a capacitor C42, wherein an inverting input terminal of the first operational amplifier U6 is connected to the signal output terminal of the audio input circuit, a forward input terminal is grounded, and an output terminal thereof is connected to the inverting input terminal, the resistor R29 and the capacitor C42 are arranged in parallel, one parallel terminal thereof is connected to the inverting input terminal of the first operational amplifier U6, and the other parallel terminal thereof is connected to the output terminal of the first operational amplifier U6.
8. The feedback type bass and audio frequency adjusting circuit according to claim 3, wherein the bass and audio frequency adjusting circuit comprises potentiometers W1 and W2, resistors R9, R10, R11, R15 and R16, capacitors C4, C5 and C6, wherein the potentiometers W1, the resistors R9, R10 and R16 and the capacitors C5 and C6 form a low-pass filter, the potentiometer W2, the resistors R11 and R15 and the capacitor C4 form a high-pass filter, the resistor R9 is sequentially connected in series with the potentiometers W1 and R10, a sliding end of the potentiometer W1 is connected to a signal input end of the feedback amplifying circuit through the resistor R16, one end of the capacitor C5 is connected between the resistor R9 and the potentiometer W1, the other end of the capacitor C5 is connected between the potentiometer W1 and the resistor R16, one end of the capacitor C6 is connected between the resistor R10 and the potentiometer W1, and the other end of the potentiometer W1 and the resistor R16; the resistor R11 is sequentially connected with the potentiometer W2 and the resistor R15 in series, and the sliding end of the potentiometer W2 is connected to the signal input end of the feedback amplifying circuit through the capacitor C4.
9. The feedback type bass and audio adjusting circuit of claim 4, wherein the feedback amplifying circuit comprises a second operational amplifier U5 and resistors R18 and R19, an inverting input terminal of the second operational amplifier U5 is connected to the signal output terminal of the bass and audio adjusting circuit, a forward input terminal is grounded, an output terminal of the second operational amplifier U5 is connected to the signal input terminal of the audio output circuit, meanwhile, an output terminal of the second operational amplifier U5 is sequentially connected in series with the resistors R18 and R19 and grounded, one end of the resistor R18 connected in series with the resistor R19 is connected to the inverting input terminal of the second operational amplifier U5.
10. The feedback bass tuning circuit of claim 6, wherein the noise cancellation circuit comprises a capacitor C7 and a resistor R17, the capacitor C7 is disposed on the feedback line of the feedback amplifier circuit, one end of the capacitor C7 is connected between the resistors R18 and R19, the other end is connected to the inverting input terminal of the second operational amplifier U5, and one end of the resistor R17 is connected to the inverting input terminal of the second operational amplifier U5, and the other end is grounded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223267397.XU CN218830531U (en) | 2022-12-07 | 2022-12-07 | Feedback type high and low sound regulating circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223267397.XU CN218830531U (en) | 2022-12-07 | 2022-12-07 | Feedback type high and low sound regulating circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN218830531U true CN218830531U (en) | 2023-04-07 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202223267397.XU Active CN218830531U (en) | 2022-12-07 | 2022-12-07 | Feedback type high and low sound regulating circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN218830531U (en) |
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2022
- 2022-12-07 CN CN202223267397.XU patent/CN218830531U/en active Active
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