CN210807633U - Microphone circuit, microphone and voice recognition system - Google Patents
Microphone circuit, microphone and voice recognition system Download PDFInfo
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- CN210807633U CN210807633U CN201921667549.0U CN201921667549U CN210807633U CN 210807633 U CN210807633 U CN 210807633U CN 201921667549 U CN201921667549 U CN 201921667549U CN 210807633 U CN210807633 U CN 210807633U
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Abstract
The utility model discloses a microphone circuit, include: the microphone circuit comprises an audio sensing unit, a first filtering unit, a decoupling bias unit, an integrated operational amplifier unit and an impedance matching unit, wherein the input end of the first filtering unit is electrically connected with the audio sensing unit, the output end of the first filtering unit is electrically connected with the input end of the decoupling bias unit, the output end of the decoupling bias unit is electrically connected with the input end of the integrated operational amplifier unit, and the power supply end of the integrated operational amplifier unit is electrically connected with the impedance matching unit; the utility model also discloses a speech recognition system, including speech recognition unit and microphone circuit, the output of unit and the signal end electric connection of speech recognition unit are put to integrated fortune, and the other end of impedance matching unit and the feed end electric connection of speech recognition unit make microphone circuit and speech recognition unit well match.
Description
Technical Field
The utility model relates to a microphone field, especially a microphone circuit and microphone and speech recognition system.
Background
At present, a traditional microphone is not designed for a voice recognition system, and generally only can have a conversation function, and because the traditional microphone has insufficient bandwidth, poor low-frequency characteristics, low signal-to-noise ratio and high distortion rate, the requirements of the voice recognition system cannot be met, and the traditional microphone cannot be matched with an external voice recognition system for use, the existing microphone circuit for improving voice recognition realizes low-frequency improvement and bandwidth expansion by adopting a triode amplifying circuit, but because the triode amplifying circuit is a non-integrated circuit, the whole circuit is complex, the debugging is not good, and the voice recognition system is difficult to be well matched.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to solve one of the technical problem that exists among the prior art at least, provide a simple structure, the microphone circuit and microphone and the speech recognition system of good debugging.
The utility model adopts the technical proposal that:
according to a first aspect of the present invention, there is provided a microphone circuit, comprising: an audio sensing unit; the input end of the first filtering unit is electrically connected with the audio induction unit; the input end of the decoupling bias unit is electrically connected with the output end of the first filtering unit; the integrated operational amplifier unit comprises an input end, an output end and a power supply end, wherein the input end of the integrated operational amplifier unit is electrically connected with the output end of the decoupling bias unit; and the impedance matching unit is electrically connected with the power supply end of the operational amplifier unit.
According to the utility model discloses a microphone circuit of first aspect, the biasing unit of decoupling includes resistance module, electric capacity C4, resistance R5 and electric capacity C3, the input of integrated operational amplifier unit includes first input and second input, the one end of resistance module respectively with electric capacity C4 one end with the first input electric connection of integrated operational amplifier unit, electric capacity C4's the other end ground connection; the other end of the resistor assembly is electrically connected with the output end of the first filtering unit; the resistor R5 and the capacitor C3 are connected in series to form a first series branch, one end of the first series branch is electrically connected with the second input end of the integrated operational amplifier unit, and the other end of the first series branch is electrically connected with the output end of the first filtering unit.
The microphone circuit according to the first aspect of the present invention further includes a resistor R1, the first pole of the output end of the audio sensing unit is grounded, the first filtering unit includes a capacitor C1 and a capacitor C2, one end of the capacitor C1 is electrically connected to the second pole of the output end of the audio sensing unit, one end of the resistor R1 and the other end of the first series branch, and the other end of the capacitor C1 is grounded; one end of the capacitor C2 is electrically connected to the other end of the resistor R1 and the other end of the resistor element, respectively, and the other end of the capacitor C2 is grounded.
According to the present invention, the first filtering unit comprises an inductor L2, a capacitor C10 and a capacitor C9, one end of the inductor L2 is electrically connected to the first pole of the output end of the audio sensing unit, the other end of the inductor L2 is electrically connected to one end of a capacitor C10 and the other end of the resistor assembly, and the other end of the capacitor C10 is grounded; one end of the capacitor C9 is electrically connected to the second pole of the output end of the audio sensing unit and the other end of the first series branch, respectively.
The utility model discloses a microphone circuit of first aspect, impedance matching unit includes electric capacity C7, electric capacity C8, resistance R7 and inductance L1, and resistance R7 establishes ties with inductance L1 and forms the second branch circuit of establishing ties, and electric capacity C7 and the parallelly connected branch circuit of formation of electric capacity C8, the one end ground connection of this branch circuit of establishing ties, the other end of this branch circuit of establishing ties respectively with fortune put the feed end of unit with the one end electric connection of the branch circuit of establishing ties of second.
The utility model discloses a microphone circuit, impedance matching unit include electric capacity C11, electric capacity C12, resistance R8 and inductance L3, electric capacity C11's one end with the feed end electric connection of unit is put to integrated fortune, electric capacity C11's the other end respectively with electric capacity C12's one end and inductance L3's one end electric connection, electric capacity C12's other end ground connection, inductance L3's the other end and resistance R8's one end electric connection, resistance R8's the other end ground connection.
According to the utility model discloses the first aspect a microphone circuit, still include second filter unit, second filter unit's output with integrated fortune is put the input electric connection of unit, second filter unit input with integrated fortune is put the output electric connection of unit.
One of the above technical solutions has at least the following beneficial effects:
the utility model relates to a microphone circuit, turn into original audio signal through audio frequency induction unit with user's speech information, filter the noise in the original audio signal by first filter unit, generate effective audio signal, the low frequency is not enough improved, the offset unit of decoupling can reduce alternating current signal and put the influence of unit to integrated fortune, and put the unit for integrated fortune and provide suitable bias voltage, and simultaneously, the frequency width can be enlarged to the impedance matching unit, reduce the loss of circuit, and because integrated fortune is put the unit and is integrated chip, make circuit structure simple, the debugging is good, can adjust first filter unit and the offset unit of decoupling better, make microphone circuit's low frequency characteristic improve in order to match external equipment better.
According to a second aspect of the present invention, there is provided a microphone comprising a housing and a microphone circuit as described above disposed in the housing.
One of the above technical solutions has at least the following beneficial effects:
the utility model relates to a microphone adopts the microphone circuit who is equipped with integrated fortune and puts the unit, and circuit structure is simple, good debugging.
According to the utility model discloses a third aspect provides a speech recognition system, including speech recognition unit and as above arbitrary a microphone circuit, the output of unit and speech recognition unit's signal end electric connection is put to integrated fortune, impedance matching unit's the other end with speech recognition unit's supply end electric connection.
One of the above technical solutions has at least the following beneficial effects:
the utility model relates to a speech recognition system, integrated fortune among the microphone circuit is put the unit and is speech recognition unit transmission audio signal, and the impedance matching unit can enlarge the frequency width, reduce the loss of circuit, makes microphone circuit and speech recognition unit's frequency width match to because fortune is put the unit and is integrated chip, circuit structure is simple, and good debugging can adjust microphone circuit better, makes microphone circuit's low frequency characteristic improve with better matching speech recognition unit.
Drawings
The following description will further describe embodiments of the present invention with reference to the accompanying drawings.
Fig. 1 is a schematic block diagram of an embodiment of a microphone circuit.
Fig. 2 is a circuit schematic diagram of an embodiment of a microphone circuit.
Fig. 3 is a circuit diagram of two embodiments of a microphone circuit.
Detailed Description
This section will describe in detail the embodiments of the present invention, preferred embodiments of the present invention are shown in the attached drawings, which are used to supplement the description of the text part of the specification with figures, so that one can intuitively and vividly understand each technical feature and the whole technical solution of the present invention, but they cannot be understood as the limitation of the protection scope of the present invention.
In the description of the present invention, it should be understood that the orientation or positional relationship indicated with respect to the orientation description, such as up, down, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the description of the present invention, a plurality of means are one or more, a plurality of means are two or more, and the terms greater than, less than, exceeding, etc. are understood as not including the number, and the terms greater than, less than, within, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.
Referring to fig. 1 to 3, the utility model relates to a microphone circuit, including audio frequency induction unit 1, first filter unit 2, decoupling offset unit 3, integrated operational amplifier unit 4 and impedance matching unit 5, the input of first filter unit 2 and audio frequency induction unit 1 electric connection, audio frequency induction unit 1 is used for turning into original audio signal with user's speech information, filters the noise in the original audio signal by first filter unit 2, generates effective audio signal, has improved the not enough problem of low frequency; the input end of the decoupling bias unit 3 is electrically connected with the output end of the first filtering unit 2, the output end of the decoupling bias unit 3 is electrically connected with the input end of the integrated operational amplifier unit 4, and the decoupling bias unit can reduce the influence of alternating current signals on the operational amplifier unit and provide proper bias voltage for the integrated operational amplifier unit 4; one end of the impedance matching unit 5 is electrically connected with the power supply terminal + Vs of the integrated operational amplifier unit 4, and the other end of the impedance matching unit 5 can be connected with an interface of an external device;
in some embodiments, the external device is a voice recognition unit, the interface of the external device includes a power supply terminal a, a power supply terminal b and a signal terminal c, the power supply terminal a of the voice recognition unit is grounded, and the other end of the impedance matching unit 5 is electrically connected with the power supply terminal b of the voice recognition unit, so that the impedance of the microphone circuit is matched with that of the voice recognition unit, thereby expanding the frequency bandwidth, reducing the loss of the circuit, and matching the frequency bandwidth of the microphone circuit with that of the voice recognition unit; the integrated operational amplifier unit 4 is an integrated chip, and operational amplifier chips such as SGM8425, F5037 and the like can be adopted, so that the circuit structure is simple, the debugging is good, the first filtering unit 2 and the decoupling bias unit 3 can be better adjusted, the low-frequency characteristic of the microphone circuit is improved, the microphone circuit can be well matched with the voice recognition unit, and the output end OUT of the integrated operational amplifier unit 4 can be electrically connected with the signal end c of the voice recognition unit to transmit the amplified audio signal to the voice recognition unit.
As shown in fig. 2, the microphone may be an electret microphone, the operational amplifier unit may be an SGM8425 chip, the decoupling bias unit 3 may reduce the influence of the ac signal on the operational amplifier unit and provide a suitable bias voltage for the SGM8425 chip, since the integrated operational amplifier unit 4 is an integrated chip, the circuit of the decoupling bias unit 3 is relatively simple and is easy to debug, the decoupling bias unit 3 includes a resistor component 31, a resistor R5, a capacitor C3 and a capacitor C4, the resistor component 31 may be a single resistor or a resistor component formed by connecting a plurality of resistors, in some embodiments, the resistor component 31 includes a resistor R2, a resistor R3 and a resistor R4, wherein the resistor R2 is connected to one end of the resistor R4 and one end of the resistor R3, the other end of the resistor R3 is grounded, the other end of the resistor R4 is connected to one end of the capacitor C4 and a second input end of the integrated operational amplifier unit 4, the other end of the capacitor C4 is grounded; the resistor R5 and the capacitor C3 are connected IN series to form a first series branch, one end of the first series branch is electrically connected with the first input end of the integrated operational amplifier unit 4, the other end of the first series branch is electrically connected with the output end of the first filtering unit 2, the first input end of the SGM8425 chip is a forward input end + IN or a reverse input end-IN, and correspondingly, the second input end of the SGM8425 chip is a reverse input end-IN or a forward input end + IN;
in some embodiments, the audio sensing unit further includes a resistor R1, a first pole of the output terminal of the audio sensing unit 1 is grounded, the first filtering unit 2 includes a capacitor C1 and a capacitor C2, one end of the capacitor C1 is electrically connected to a second pole of the output terminal of the audio sensing unit 1, one end of the resistor R1 and the other end of the first series branch, respectively, and the other end of the capacitor C1 is grounded; one end of the capacitor C2 is electrically connected to the other end of the resistor R1 and the other end of the resistor assembly 31, and the other end of the capacitor C2 is grounded, so that the first filtering unit can filter out noise in the original audio signal, generate an effective audio signal, and improve the problem of insufficient low frequency;
in some embodiments, a zener diode D1 is further disposed in the first filtering unit 2, one end of the parallel connection of the capacitor C2 and the zener diode D1 is grounded, and the other end of the parallel connection of the capacitor C2 and the zener diode D1 is connected to the other end of the resistor R1;
one end of the impedance matching unit 5 is electrically connected to the power supply terminal + Vs of the integrated operational amplifier unit 4, the other end of the impedance matching unit 5 is electrically connected to the power supply terminal b of the voice recognition unit to expand the bandwidth and reduce the loss of the circuit, so that the bandwidth of the microphone circuit is matched with the bandwidth of the voice recognition unit, in the impedance matching unit 5, a pi-type matching circuit is adopted to realize the adjustment of the quality factor of the circuit and improve the bandwidth, the impedance matching unit 5 comprises a capacitor C7, a capacitor C8, a resistor R7 and an inductor L1, the resistor R7 is connected in series with the inductor L1 to form a second series branch, one end of the second series branch can be connected with the power supply terminal b of the voice recognition unit, the capacitor C7 and the capacitor C8 are connected in parallel to form a parallel branch, one end of the parallel branch is grounded, and the other end of the parallel branch is electrically connected with the power supply terminal + Vs of the integrated operational amplifier unit 4 and the other end of, the impedance of the microphone circuit is matched with the impedance of the voice recognition unit by debugging the impedance matching unit 5, so that the frequency width of the microphone circuit is matched with that of the voice recognition unit;
in some embodiments, the signal terminal C of the voice recognition unit and the power supply terminal b are the same port, and the output terminal OUT of the SGM8425 chip is electrically connected to the load terminal b of the voice recognition unit through the filter capacitor C6 to transmit the amplified audio signal to the voice recognition unit; in some embodiments, the zener diode D2 is electrically connected to the speech recognition unit, and the filter capacitor C6 is connected to one end of the zener diode D2 so that the speech recognition unit can receive a stable audio signal;
the voice recognition device further comprises a second filtering unit 7, an output end of the second filtering unit 7 is electrically connected with an input end of the SGM8425 chip, an input end of the second filtering unit 7 is electrically connected with an output end OUT of the SGM8425 chip, the second filtering unit 7 can select a corresponding first-order or second-order low-pass, high-pass or band-pass filtering circuit according to the bandwidth requirement of the voice recognition unit, for example, the second filtering unit 7 IN fig. 2 adopts a first-order low-pass filtering circuit, a resistor R6 and a capacitor C5 are connected IN parallel, one end of the resistor R6 is electrically connected with a reverse input end-IN of the SGM8425 chip, the other end of the resistor R6 is electrically connected with the output end OUT of the SGM8425 chip, a filtering feedback.
As shown in fig. 3, the microphone may be a silicon microphone, the operational amplifier unit is an SGM8425 chip, the first filtering unit 2 includes an inductor L2, a capacitor C10 and a capacitor C9, one end of the inductor L2 is electrically connected to the first pole of the output end of the audio sensing unit 1, the other end of the inductor L2 is electrically connected to one end of the capacitor C10 and the other end of the resistor element 31, and the other end of the capacitor C10 is grounded; one end of the capacitor C9 is electrically connected to the second pole of the output end of the audio sensing unit 1 and the other end of the first series branch respectively;
in some embodiments, zener diodes D2 and D3 are further added, one end of the parallel branch of the capacitor C10 and the zener diode D2 is grounded, one end of the parallel branch of the capacitor C9 and the zener diode D3 is grounded, a first pole of an output end of the audio sensing unit 1 is connected to the other end of the parallel branch of the capacitor C10 and the zener diode D2 through a series inductor L2, respectively, a second pole of the output end of the audio sensing unit 1 is connected to the other end of the parallel branch of the capacitor C9 and the diode D3, and the inductor L2, the capacitor C9 and the capacitor C10 can filter out noise in an original audio signal, generate an effective audio signal, and improve the problem of insufficient low frequency;
in the impedance matching unit 5, an L-type matching circuit is adopted, so that the quality factor of the circuit can be adjusted, the frequency bandwidth is improved, the impedance matching unit 5 comprises a capacitor C11, a capacitor C12, a resistor R8 and an inductor L3, one end of the capacitor C11 is electrically connected with the power supply terminal + Vs of the integrated operational amplifier unit 4, the other end of the capacitor C11 is electrically connected with one end of a capacitor C12 and one end of an inductor L3 respectively, the other end of the capacitor C12 is grounded, the other end of the inductor L3 is connected with one end of the resistor R8 and the signal terminal b of the voice recognition unit, the other end of the resistor R8 is grounded, by debugging the impedance matching unit 5, the impedance of the microphone circuit is matched with the impedance of the voice recognition unit, so that the frequency width of the microphone circuit is matched with the frequency width of the voice recognition unit, a voltage stabilizing diode D5 is arranged between the power supply end a and the power supply end b of the voice recognition unit to stabilize the voltage of the voice recognition unit; in some embodiments, the output terminal OUT of the SGM8425 chip is electrically connected to the signal terminal c of the speech recognition unit to transmit the amplified audio signal to the speech recognition unit.
The utility model relates to a microphone circuit, circuit structure is simple, the debugging is good, can carry on multiple external equipment and use, especially carries on-vehicle speech recognition unit and uses, and this microphone circuit's low frequency characteristic improves to its frequency width can well match with on-vehicle speech recognition unit's frequency width.
It is readily understood by those skilled in the art that the above-described preferred modes can be freely combined and superimposed without conflict.
The above is only the preferred embodiment of the present invention, not limiting the patent scope of the present invention, all of which are under the concept of the present invention, the equivalent structure transformation made by the contents of the specification and the drawings is utilized, or the direct or indirect application is included in other related technical fields in the patent protection scope of the present invention.
Claims (9)
1. A microphone circuit, comprising:
an audio sensing unit (1);
the input end of the first filtering unit (2) is electrically connected with the output end of the audio induction unit (1);
the input end of the decoupling bias unit (3) is electrically connected with the output end of the first filtering unit (2);
the integrated operational amplifier unit (4) comprises an input end, an output end and a power supply end, the input end of the integrated operational amplifier unit (4) is electrically connected with the output end of the decoupling bias unit (3), and the output end of the integrated operational amplifier unit can be electrically connected with external equipment;
the impedance matching unit (5), one end of the impedance matching unit (5) with the power supply end electric connection of integrated operational amplifier unit (4), the other end of impedance matching unit (5) can with external equipment electric connection.
2. A microphone circuit according to claim 1, wherein: the decoupling bias unit (3) comprises a resistor component (31), a capacitor C4, a resistor R5 and a capacitor C3, the input end of the integrated operational amplifier unit (4) comprises a first input end and a second input end, one end of the resistor component (31) is electrically connected with one end of the capacitor C4 and the first input end of the integrated operational amplifier unit (4), and the other end of the capacitor C4 is grounded; the other end of the resistor component (31) is electrically connected with the output end of the first filtering unit (2); the resistor R5 and the capacitor C3 are connected in series to form a first series branch, one end of the first series branch is electrically connected with the second input end of the integrated operational amplifier unit (4), and the other end of the first series branch is electrically connected with the output end of the first filtering unit (2).
3. A microphone circuit according to claim 2, wherein: the audio frequency sensing unit further comprises a resistor R1, a first pole of an output end of the audio frequency sensing unit (1) is grounded, the first filtering unit (2) comprises a capacitor C1 and a capacitor C2, one end of the capacitor C1 is electrically connected with a second pole of the output end of the audio frequency sensing unit (1), one end of the resistor R1 and the other end of the first series branch respectively, and the other end of the capacitor C1 is grounded; one end of the capacitor C2 is electrically connected with the other end of the resistor R1 and the other end of the resistor component (31), and the other end of the capacitor C2 is grounded.
4. A microphone circuit according to claim 2, wherein: the first filtering unit (2) comprises an inductor L2, a capacitor C10 and a capacitor C9, one end of the inductor L2 is electrically connected with a first pole of the output end of the audio sensing unit (1), the other end of the inductor L2 is electrically connected with one end of a capacitor C10 and the other end of the resistor component (31), and the other end of the capacitor C10 is grounded; one end of the capacitor C9 is electrically connected to the second pole of the output end of the audio sensing unit (1) and the other end of the first series branch respectively.
5. A microphone circuit according to claim 1, wherein: the impedance matching unit (5) comprises a capacitor C7, a capacitor C8, a resistor R7 and an inductor L1, the resistor R7 is connected with the inductor L1 in series to form a second series branch, the capacitor C7 is connected with the capacitor C8 in parallel to form a parallel branch, one end of the parallel branch is grounded, and the other end of the parallel branch is electrically connected with the power supply end of the integrated operational amplifier unit (4) and one end of the second series branch.
6. A microphone circuit according to claim 1, wherein: the impedance matching unit (5) comprises a capacitor C11, a capacitor C12, a resistor R8 and an inductor L3, one end of the capacitor C11 is electrically connected with the power supply end of the integrated operational amplifier unit (4), the other end of the capacitor C11 is electrically connected with one end of a capacitor C12 and one end of an inductor L3, the other end of the capacitor C12 is grounded, the other end of the inductor L3 is electrically connected with one end of the resistor R8, and the other end of the resistor R8 is grounded.
7. A microphone circuit according to claim 1, wherein: the integrated operational amplifier further comprises a second filtering unit (7), wherein the input end of the second filtering unit (7) is electrically connected with the output end of the integrated operational amplifier unit (4), and the output end of the second filtering unit (7) is electrically connected with the input end of the integrated operational amplifier unit (4).
8. A microphone, characterized by: comprising a housing and a microphone circuit as claimed in any one of claims 1 to 7 arranged in the housing.
9. A speech recognition system characterized by: comprising a voice recognition unit and a microphone circuit according to any of claims 1 to 7, wherein the output terminal of the integrated operational amplifier unit (4) is electrically connected to the signal terminal of the voice recognition unit, and the other terminal of the impedance matching unit (5) is electrically connected to the power supply terminal of the voice recognition unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921667549.0U CN210807633U (en) | 2019-09-30 | 2019-09-30 | Microphone circuit, microphone and voice recognition system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921667549.0U CN210807633U (en) | 2019-09-30 | 2019-09-30 | Microphone circuit, microphone and voice recognition system |
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| Publication Number | Publication Date |
|---|---|
| CN210807633U true CN210807633U (en) | 2020-06-19 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201921667549.0U Active CN210807633U (en) | 2019-09-30 | 2019-09-30 | Microphone circuit, microphone and voice recognition system |
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| CN (1) | CN210807633U (en) |
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- 2019-09-30 CN CN201921667549.0U patent/CN210807633U/en active Active
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Address after: 341000, Ganzhou, Jiangxi province Yudu County town on the upper European Industrial Park Patentee after: Tianjian electroacoustic Co.,Ltd. Address before: 342300 Yudu City, Ganzhou Province town of tribute on the European Industrial Park Patentee before: JIANGXI TIANJIAN ELECTROACOUSTIC Co.,Ltd. |
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