CN209845280U - Voice sound pickup circuit and device - Google Patents
Voice sound pickup circuit and device Download PDFInfo
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- CN209845280U CN209845280U CN201920880978.XU CN201920880978U CN209845280U CN 209845280 U CN209845280 U CN 209845280U CN 201920880978 U CN201920880978 U CN 201920880978U CN 209845280 U CN209845280 U CN 209845280U
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Abstract
A voice sound pickup circuit and a device thereof comprise a control module, an echo acquisition module, a sampling module, an analog microphone module, a digital power amplifier module and a digital microphone module, the first audio signal collected by the echo collection module and the external sound including the voice command collected by the analog microphone module are transmitted to the control module through the sampling module, and then the control module performs noise elimination processing on the first audio signal and the external sound to obtain the voice command, and the control module performs noise elimination processing on a feedback signal fed back to the control module by the digital power amplifier module and external sound including a voice instruction acquired by the digital microphone module so as to obtain the voice instruction, so that the voice instruction can be accurately obtained under the condition of loudspeaker playing and can be obtained in different modes, and the problems of single selection, poor adaptability in different scenes and poor voice control capability in the traditional technical scheme are solved.
Description
Technical Field
The utility model belongs to the technical field of pronunciation, especially, relate to a pronunciation stereo set pickup circuit and device.
Background
At present, traditional intelligence pronunciation stereo set pickup circuit generally only adopts analog microphone module or digital microphone module, is unfavorable for the development of many product forms and at stereo set broadcast sound source in-process, and the voice when pronunciation are controlled the stereo set is covered by the sound source of stereo set broadcast very easily, leads to the unable pickup of stereo set to go out people's voice operation instruction, experiences very poorly, especially more obvious when the sound source sound of stereo set broadcast is great far away from the stereo set simultaneously at the people.
Therefore, the traditional technical scheme has the problems of single selection, poor adaptability of different scenes and poor voice control capability.
SUMMERY OF THE UTILITY MODEL
In view of this, the embodiment of the present invention provides a voice sound pickup circuit and device, which aim to solve the problems of single selection, poor adaptability to different scenes and poor voice control capability existing in the conventional technical solution.
The utility model discloses a first aspect of the embodiment provides a pronunciation stereo set pickup circuit, is connected with loudspeaker, pronunciation stereo set pickup circuit includes: a control module; the digital power amplifier module is connected with the loudspeaker and the control module and used for converting a first signal output by the control module into a first audio signal, transmitting the first audio signal to the loudspeaker, generating a feedback signal according to the first audio signal and transmitting the feedback signal to the control module; the echo acquisition module is connected with the input end of the loudspeaker and the output end of the digital power amplifier module and is used for acquiring the first audio signal; the analog microphone module is used for collecting external sound and converting the external sound into a second audio signal, wherein the external sound comprises a voice instruction and a first audio frequency played by the loudspeaker according to the first audio signal; the sampling module is connected with the control module, the analog microphone module and the echo acquisition module, and is used for converting a first audio signal acquired by the echo acquisition module into a first digital signal, converting a second audio signal into a second digital signal and transmitting the first digital signal and the second digital signal to the control module; the digital microphone module is connected with the control module and is used for acquiring the outside sound, converting the outside sound into a third digital signal and transmitting the third digital signal to the control module; the control module performs noise elimination processing on the first digital signal and the second digital signal according to a first preset rule to obtain the voice command, or performs noise elimination processing on the feedback signal and the third digital signal according to a second preset rule to obtain the voice command.
In one embodiment, the sampling module comprises: each pair of differential signal input ends of the analog-to-digital conversion chip is connected with the analog microphone module and the loudspeaker, a bus end of the analog-to-digital conversion chip is connected with a bus end of the control module, a bus address configuration end of the analog-to-digital conversion chip is connected with a second end of the first resistor and a first end of the second resistor, a second end of the second resistor is grounded, a first end of the first resistor is externally connected with a direct current voltage with a first end of the first magnetic bead, a second end of the first magnetic bead is connected with a first end of the first capacitor and a first end of the second magnetic bead, a second end of the first capacitor is grounded, and a second end of the second magnetic bead is connected with a first end of the second capacitor and an analog power supply end of the analog-to-digital conversion chip, the second end of the second capacitor is grounded, and the voltage stabilizing end of the analog-to-digital conversion chip is grounded through the third capacitor.
In one embodiment, the digital power amplifier module includes: the signal input and output end of the digital power amplifier chip is connected with the control module, a first terminal of a first differential output opposite end of the digital power amplifier chip is connected with a first end of the third magnetic bead, a second terminal of the first differential output opposite end of the digital power amplifier chip is connected with a first end of the fourth magnetic bead, a second end of the third magnetic bead and a second end of the fourth magnetic bead are connected with a first end of the third resistor in a common mode, a second end of the third resistor is connected with the anode of the horn, a first terminal of a second differential output opposite end of the digital power amplifier chip is connected with a first end of the fifth magnetic bead, a second terminal of a second differential output opposite end of the digital power amplifier chip is connected with a first end of the sixth magnetic bead, the second end of the fifth magnetic bead and the second end of the sixth magnetic bead are connected to the first end of the fourth resistor in common, and the second end of the fourth resistor is connected to the negative electrode of the horn.
In one embodiment, the echo acquisition module comprises: the first DC blocking unit is connected with the loudspeaker and is used for isolating a DC component in the first audio signal; the input end of the multi-order low-pass filter unit is connected with the output end of the first stopping unit, and the multi-order low-pass filter unit is used for filtering high-frequency interference components in the first audio signal; the input end of the amplitude limiting unit is connected with the output end of the multi-order low-pass filtering unit, the ground end of the amplitude limiting unit is grounded, and the amplitude limiting unit is used for controlling the output amplitude of the first audio signal; the input end of the first radio frequency interference filtering unit is connected with the output end of the amplitude limiting unit, the output end of the first radio frequency interference filtering unit is grounded, and the first radio frequency interference filtering unit is used for filtering radio frequency interference components in the first audio signal; the differential pair internal capacitance unit is connected with the amplitude limiting unit and is used for filtering out differential pair internal interference components of the first audio signal; and the second blocking unit is connected with the amplitude limiting unit and the sampling module and is used for isolating the direct current component of the first audio signal again.
In one embodiment, the multi-order low-pass filter unit includes a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, and a ninth capacitor, a first end of the fifth resistor is connected to the first terminal of the output terminal of the first dc-blocking unit, a second end of the fifth resistor is connected to the first end of the sixth resistor and the first end of the fourth capacitor, a second end of the sixth resistor is connected to the first end of the seventh resistor and the first end of the fifth capacitor, a second end of the seventh resistor and a first end of the sixth capacitor are connected in common to serve as the first terminal of the output terminal of the multi-order low-pass filter unit, and a first end of the eighth resistor is connected to the second terminal of the output terminal of the first dc-blocking unit, the second end of the eighth resistor is connected to the first end of the ninth resistor and the first end of the seventh capacitor, the second end of the ninth resistor is connected to the first end of the tenth resistor and the first end of the eighth capacitor, the second end of the tenth resistor and the first end of the ninth capacitor are connected in common to serve as the second terminal of the output end of the multi-stage low-pass filter unit, and the second end of the fourth capacitor, the second end of the fifth capacitor, the second end of the sixth capacitor, the second end of the seventh capacitor, the second end of the eighth capacitor and the second end of the ninth capacitor are connected in common to ground.
In one embodiment, the clipping unit includes an eleventh resistor, a twelfth resistor, a thirteenth resistor, and a fourteenth resistor, a first end of the eleventh resistor is a first terminal of the input terminal of the clipping unit, a second end of the eleventh resistor and a first end of the twelfth resistor are commonly connected to serve as a first terminal of the output terminal of the clipping unit, a first end of the thirteenth resistor is a first terminal of the input terminal of the clipping unit, a second end of the thirteenth resistor and a first end of the fourteenth resistor are commonly connected to serve as a second terminal of the output terminal of the clipping unit, and a second end of the twelfth resistor and a second end of the fourteenth resistor are commonly connected to ground.
In one embodiment, the microphone system further comprises an analog microphone access module, wherein the analog microphone access module is connected with the analog microphone module and the sampling module, and is used for acquiring the second audio signal and transmitting the second audio signal to the sampling module.
In one embodiment, the analog microphone access module comprises: the first end of the filtering unit is externally connected with a bias voltage, the second end of the filtering unit is grounded, and the filtering unit is used for filtering the bias voltage and outputting the filtered bias voltage to the analog microphone module; the first end of the low-pass filtering unit is connected with the anode of the analog microphone module, the second end of the low-pass filtering unit is connected with the cathode of the analog microphone module, and the low-pass filtering unit is used for filtering out high-frequency interference components of the second audio signal; a first input end of the second radio frequency interference filtering unit is connected with the anode of the analog microphone module, a second input end of the second radio frequency interference filtering unit is connected with the cathode of the analog microphone module, and the second radio frequency interference filtering unit is used for filtering radio frequency interference components of the second audio signal; a power supply terminal of the dc bias unit is connected to the first terminal of the filter unit and the bias voltage, a ground terminal of the dc bias unit is grounded, a first output terminal of the dc bias unit is connected to the anode of the analog microphone module, a second output terminal of the dc bias unit is connected to the cathode of the analog microphone module, and the dc bias unit is configured to provide dc bias for the analog microphone module; a first input end of the buffer unit is connected with a positive electrode of the analog microphone module and a first output end of the direct current bias unit, a second input end of the buffer unit is connected with a negative electrode of the analog microphone module and a second output end of the direct current bias unit, and the buffer unit is used for buffering current impact brought by the direct current bias unit; and a third blocking unit, a first input end of the third blocking unit is connected with a first output end of the buffer unit and a first terminal of a first differential input end of the sampling module, a second input end of the third blocking unit is connected with a second output end of the buffer unit and a second terminal of the first differential input end of the sampling module, and the third blocking unit is used for isolating the direct current component of the second audio signal and then outputting the second audio signal to the sampling module.
In one embodiment, the dc bias unit includes a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, and a tenth capacitor, a first terminal of the fifteenth resistor is a power supply terminal of the dc bias unit, a second terminal of the fifteenth resistor is connected to a first terminal of the tenth capacitor and a first terminal of the sixteenth resistor, a second terminal of the sixteenth resistor is a first output terminal of the dc bias unit, a first terminal of the seventeenth resistor is a second output terminal of the dc bias unit, a second terminal of the seventeenth resistor is connected to a first terminal of the eighteenth resistor and a second terminal of the tenth capacitor, and a second terminal of the eighteenth resistor is a ground terminal of the dc bias unit.
The utility model provides a second aspect of the embodiment provides a pronunciation stereo set pickup apparatus, include: loudspeaker and like the first aspect of the embodiment of the utility model provides an arbitrary pronunciation stereo set pickup circuit.
The sound pickup circuit and the sound pickup device for the voice sound comprise a control module, an echo acquisition module, a sampling module, an analog microphone module, a digital power amplifier module and a digital microphone module, wherein a first audio signal acquired by the echo acquisition module and external sound of a first audio frequency acquired by the analog microphone module and comprising a voice instruction and a loudspeaker play are transmitted to the control module through the sampling module and then subjected to noise elimination by the control module to obtain the voice instruction, and a feedback signal fed back to the control module by the digital power amplifier module and the external sound of the first audio frequency acquired by the digital microphone module and comprising the voice instruction and the loudspeaker play are subjected to noise elimination through the control module to obtain the voice instruction Poor adaptability to different scenes and poor voice control capability.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments or the prior art descriptions will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive labor.
Fig. 1 is a schematic circuit diagram of a voice sound pickup circuit according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of an exemplary digital microphone module of the audio pick-up circuit of FIG. 1;
FIG. 3 is a schematic diagram of an exemplary circuit for a sampling module in the voice sound pickup circuit of FIG. 1;
fig. 4 is a schematic diagram of an exemplary circuit of a digital power amplifier module in the voice sound pickup circuit shown in fig. 1;
fig. 5 is a schematic diagram of an exemplary circuit of an echo collection module in the voice sound pickup circuit shown in fig. 1;
FIG. 6 is a schematic diagram of a specific example circuit of the echo acquisition module shown in FIG. 5;
fig. 7 is a schematic circuit diagram of another voice sound pickup circuit according to an embodiment of the present invention;
fig. 8 is an exemplary circuit schematic of an analog microphone access module in the voice sound pick-up circuit shown in fig. 7;
fig. 9 is a schematic circuit diagram of a specific example of the analog microphone access module shown in fig. 8.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1, a circuit diagram of a voice sound pickup circuit according to an embodiment of the present invention is shown, for convenience of description, only the parts related to the embodiment are shown, and detailed descriptions are as follows:
the pronunciation stereo set pickup circuit in this embodiment is connected with loudspeaker 100, and pronunciation stereo set pickup circuit includes: the microphone comprises an analog microphone module 200, a digital microphone module 300, a control module 400, an echo acquisition module 500, a sampling module 600 and a digital power amplifier module 700, wherein the output end of the analog microphone module 200 is connected with the sampling module 600, the digital microphone module 300 is connected with the control module 400, the control module 400 is connected with the digital microphone module 300, the sampling module 600 and the digital power amplifier module 700, the sampling module 600 is connected with the analog microphone module 200, the echo acquisition module 500 and the control module 400, and the digital power amplifier module 700 is connected with the control module 400 and a loudspeaker 100; the digital power amplifier module 700 is configured to convert the first signal output by the control module 400 into a first audio signal, transmit the first audio signal to the speaker 100, and generate a feedback signal according to the first audio signal and transmit the feedback signal to the control module 400; the echo collection module 500 is configured to collect a first audio signal; the analog microphone module 200 is configured to collect external sound and convert the external sound into a second audio signal, where the external sound includes a voice instruction and a first audio frequency played by the speaker 100 according to the first audio signal; the sampling module 600 is configured to convert the first audio signal acquired by the echo acquisition module 500 into a first digital signal, convert the second audio signal into a second digital signal, and transmit the first digital signal and the second digital signal to the control module 400; the digital microphone module 300 is configured to collect external sounds, convert the external sounds into a third digital signal, and transmit the third digital signal to the control module 400; the control module 400 performs noise elimination on the first digital signal and the second digital signal according to a first preset rule to obtain a voice command, or performs noise elimination on the feedback signal and the third digital signal according to a second preset rule to obtain a voice command.
It should be understood that the analog microphone module 200 may be composed of one or two and more analog microphones; the digital microphone module 300 may be composed of one or two or more digital microphones; the control module 400 may be constituted by a microprocessor; the digital power amplifier module 700 may be composed of a digital power amplifier integrated chip, a resistor, a capacitor, magnetic beads, and the like; the echo collection module 500 may be composed of one or more devices or chips with filtering and anti-interference functions; the sampling module 600 may be formed by an analog-to-digital conversion chip U1; the first preset rule may be a subtraction processing rule, that is, a voice instruction is obtained by performing subtraction processing on a second digital signal converted from a second audio signal including the voice instruction and the first audio signal and a first digital signal converted from a first audio signal including the first audio; the second preset rule is the same as the first preset rule; in this embodiment, the priorities of the first preset rule and the second preset rule are set according to the signal strengths of the second digital signal and the third digital signal, and optionally, the priorities of the first preset rule and the second preset rule may also be set according to the requirements of the application scenario in other embodiments.
The voice sound pickup circuit in the embodiment comprises a control module 400, an echo collection module 500, a sampling module 600, an analog microphone module 200, a digital power amplifier module 700 and a digital microphone module 300, wherein a first audio signal collected by the echo collection module 500 and an external sound collected by the analog microphone module 200 and including a voice instruction are transmitted to the control module 400 through the sampling module 600, and then are subjected to noise elimination by the control module 400 to obtain the voice instruction, and a feedback signal fed back to the control module 400 by the digital power amplifier module 700 and the external sound collected by the digital microphone module 300 and including the voice instruction and the first audio frequency played by the loudspeaker 100 are subjected to noise elimination by the control module 400 to obtain the voice instruction, so that the voice instruction can be accurately obtained under the condition that the loudspeaker 100 plays and can be obtained in different modes, the problems of single selection, poor adaptability of different scenes and poor voice control capability in the traditional technical scheme are solved.
It should be understood that the voice Sound pickup circuit in this embodiment may further include a voice interaction module, the voice interaction module is connected to the control module 400 and the other analog microphone module 200, the voice interaction module is configured to perform noise reduction filtering and the like on an input signal of the other analog microphone module 200 and input the processed input signal into the control module 400, and the voice interaction module may be formed by other modules supporting I2S (Inter-IC Sound, integrated circuit built-in audio bus), such as an ASR-02 series module.
It should be understood that the voice sound pickup circuit in this embodiment may further include a wireless module, a storage module, a serial interface module, a power supply module, and the like, where the wireless module, the storage module, the serial interface module, and the power supply module are connected to the control module 400, and the wireless module may be formed by a bluetooth module and/or a WIFI module; the storage module may be constituted by a memory; the serial interface module can be composed of a USB interface; the power supply module may be constituted by a battery.
Referring to fig. 2, in an embodiment, the digital microphone module 300 in the present embodiment includes one or two or more digital microphones supporting a PDM (Pulse Density Modulation) protocol, and a signal inside the digital microphone module 300 is amplified by an analog preamplifier and modulated by a PDM modulator to output a high-rate single-bit signal. Referring to fig. 2, the digital microphone module 300 shown in fig. 2 includes a first digital microphone 310 and a second digital microphone module 320, the control module 400 outputs a main clock signal PDM _ DCLK to the first digital microphone 310 and the second digital microphone module 320, and 1-bit data on the data line PDM _ DIN0 is valid at a rising edge or a falling edge of the main clock signal PDM _ DCLK. When the digital microphone module 300 supports two-channel operation, one digital microphone is active on the data line on the rising edge of the master clock, the other digital microphone is active on the falling edge, and the data output is high impedance on the inactive edge. The data lines and clock lines of the two digital microphones are connected together, and the different digital microphones are distinguished by the high and low levels of PIN2 of the connector J12 and the connector J13.
Referring to fig. 3, in one embodiment, the sampling module 600 includes: an analog-digital conversion chip U1, a first resistor R1, a second resistor R2, a first magnetic bead FB1, a second magnetic bead FB2, a first capacitor C1, a second capacitor C2 and a third capacitor C3, wherein each pair of differential signal input terminals of the analog-digital conversion chip U1 is connected to the analog microphone module 200 and the speaker 100, a bus terminal of the analog-digital conversion chip U1 is connected to a bus terminal of the control module 400, a bus address configuration terminal of the analog-digital conversion chip U1 is connected to a second terminal of the first resistor R1 and a first terminal of the second resistor R2, a second terminal of the second resistor R2 is grounded, a first terminal of the first resistor R1 is connected to a first terminal of the first magnetic bead 1, a second terminal of the first FB1 is connected to a first terminal of the first capacitor C1 and a first terminal of the second magnetic bead FB2, a second terminal of the first capacitor C1 is grounded, a second terminal of the second magnetic bead is connected to a power supply terminal of the second capacitor C5928 and a power supply terminal of the analog-digital conversion chip U1, the second terminal of the second capacitor C2 is grounded, and the regulated terminal of the analog-to-digital conversion chip U1 is grounded through the third capacitor C3.
It should be understood that the analog-to-digital conversion chip U1 of the sampling module 600 in this embodiment is a TI PCM1864 four-channel chip, and in other embodiments, other analog-to-digital conversion chips U1 may be used. The sampling module 600 in this embodiment adopts a differential mode, where a first pair of differential signal input terminals (PIN1 and PIN3) of the analog-to-digital conversion chip U1 is connected to an input audio signal of the first analog microphone MIC1 in the analog microphone module 200, and a first pair of differential signal input terminals (PIN1 and PIN3) of the analog-to-digital conversion chip U1 is used for signal transmission between the first analog microphone MIC1 and the sampling module 600; a second pair of differential signal input terminals (PIN2 and PIN4) of the analog-to-digital conversion chip U1 is connected to the input audio signal of the second analog microphone MIC2 in the analog microphone module 200, and a second pair of differential signal input terminals (PIN2 and PIN4) of the analog-to-digital conversion chip U1 is used for signal transmission between the second analog microphone MIC2 and the sampling module 600; the I2S interfaces (PIN15, PIN16, PIN17, PIN18) and the I2C (Inter-Integrated Circuit bus) interfaces (PIN23, PIN24) of the analog-to-digital conversion chip U1 are bus terminals of the analog-to-digital conversion chip U1 and are used for data transmission between the sampling module 600 and the control module 400; a PIN25 of the analog-digital conversion chip U1 is an I2C address configuration end, different I2C address configurations can be performed by adjusting the first resistor R1 and the second resistor R2, for example, the high and low levels of the I2C address configuration end are controlled by adjusting the resistances of the first resistor R1 and the second resistor R2 or by selecting the mode of mounting the first resistor R1 or the second resistor R2, so that different I2C address configuration ends are configured; the PIN5 of the analog-to-digital conversion chip U1 may be used to provide a bias voltage for the analog microphone module 200.
Referring to fig. 4, in an embodiment, the digital power amplifier module 700 includes: a digital power amplifier chip U9, a third magnetic bead FB3, a fourth magnetic bead FB4, a fifth magnetic bead FB5, a sixth magnetic bead FB6, a third resistor R3 and a fourth resistor R4, wherein a signal input/output end of the digital power amplifier chip U9 is connected with the control module 400, a first terminal of a first differential output opposite end of the digital power amplifier chip U9 is connected with a first end of the third magnetic bead FB3, a second terminal of the first differential output opposite end of the digital power amplifier chip U9 is connected with a first end of the fourth magnetic bead FB4, a second end of the third magnetic bead FB3 and a second end of the fourth magnetic bead FB4 are connected with a first end of the third resistor R3, a second end of the third resistor R3 is connected with an anode of the horn 100, a first terminal of a second differential output opposite end of the digital power amplifier chip U9 is connected with a first end of the fifth magnetic bead FB5, a second terminal of the second differential output opposite end of the digital power amplifier chip U9 is connected with a second end 6 of the sixth magnetic bead FB2, the second end of the fifth magnetic bead FB5 and the second end of the sixth magnetic bead FB6 are connected to the first end of the fourth resistor R4, and the second end of the fourth resistor R4 is connected to the negative electrode of the horn 100.
The model of the digital power amplifier chip U9 in this embodiment is AD82584F, and in other embodiments, the digital power amplifier chip U9 of other models may be used, and the feedback signal of the first audio signal output after the adjustment of the equalizer inside the digital power amplifier chip U9 is returned to the control module 400, so that the artificial intelligence sound equipment that needs echo cancellation can be conveniently applied. The switching between the single-channel mode and the dual-channel mode can be realized by adjusting a peripheral circuit at the output end of the digital power amplifier chip U9, for example, by adjusting the third magnetic bead FB3, the fourth magnetic bead FB4, the fifth magnetic bead FB5 and the sixth magnetic bead FB 6.
Referring to fig. 5, in an embodiment, to facilitate understanding of the structure of the echo acquisition module 500, in the embodiment, taking the echo acquisition module 500 as an example, the echo acquisition module 500 includes: a first blocking unit 511, a multi-order low-pass filtering unit 512, a limiting unit 513, a first radio frequency interference filtering unit 514, a differential pair internal capacitance unit 515 and a second blocking unit 516; the first stopping unit 511 is connected with the loudspeaker 100, the input end of the multi-order low-pass filtering unit 512 is connected with the output end of the first stopping unit 511, the input end of the amplitude limiting unit 513 is connected with the output end of the multi-order low-pass filtering unit 512, the ground end of the amplitude limiting unit 513 is grounded, the input end of the first radio frequency interference filtering unit 514 is connected with the output end of the amplitude limiting unit 513, the output end of the first radio frequency interference filtering unit 514 is grounded, the differential pair internal capacitance unit 515 is connected with the amplitude limiting unit 513, and the second stopping unit 516 is connected with the amplitude limiting unit 513 and the sampling module 600; the first dc blocking unit 511 is configured to isolate a dc component in the first output signal, the multi-order low-pass filtering unit 512 is configured to filter a high-frequency interference component in the first audio signal, the amplitude limiting unit 513 controls an output amplitude of the first audio signal, the first rf interference filtering unit 514 is configured to filter a radio-frequency interference component in the first audio signal, the differential pair internal capacitor unit 515 is configured to filter a differential pair internal interference component of the first audio signal, and the second dc blocking unit 516 is configured to isolate the dc component of the first audio signal again.
Referring to fig. 6, in an embodiment, the first dc blocking unit 511 includes an eleventh capacitor C11 and a twelfth capacitor C12, wherein a first end of the eleventh capacitor C11 is connected to the anode of the speaker 100, a first end of the twelfth capacitor C12 is connected to the cathode of the speaker 100, and a second end of the eleventh capacitor C11 and a second end of the twelfth capacitor C12 are differential output terminals of the first dc blocking unit 511.
Referring to fig. 6, in an embodiment, the multi-stage low-pass filter unit 512 includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, and a ninth capacitor C9, a first end of the fifth resistor R5 is connected to a first terminal of an output terminal of the first dc-blocking unit 511, a second end of the fifth resistor R5 is connected to a first end of the sixth resistor R6 and a first end of the fourth capacitor C4, a second end of the sixth resistor R6 is connected to a first end of the seventh resistor R7 and a first end of the fifth capacitor C5, a second end of the seventh resistor R7 and a first end of the sixth capacitor C6 are connected together as a first terminal of the output terminal of the multi-stage low-pass filter unit, a first end of the eighth resistor R8 is connected to the first terminal of the first dc-blocking unit 512, a second end of the eighth resistor R8 is connected to a first end of the ninth resistor R9 and a first end of the seventh capacitor C7, a second end of the ninth resistor R9 is connected to a first end of the tenth resistor R10 and a first end of the eighth capacitor C8, a second end of the tenth resistor R10 and a first end of the ninth capacitor C9 are commonly connected to a second terminal of the output terminal of the multi-stage low-pass filter unit 512, and a second end of the fourth capacitor C4, a second end of the fifth capacitor C5, a second end of the sixth capacitor C6, a second end of the seventh capacitor C7, a second end of the eighth capacitor C8, and a second end of the ninth capacitor C9 are commonly connected to ground.
It should be understood that, in the multi-order low-pass filtering unit 512 in this embodiment, by using two third-order low-pass filtering channels composed of a resistor and a capacitor, the first output signal may be attenuated the least in the target pass band, and the attenuation gradient outside the target pass band is the greatest, so as to obtain the first target signal.
Referring to fig. 6, in an embodiment, the clipping unit 513 includes an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, and a fourteenth resistor R14, a first end of the eleventh resistor R11 is a first terminal of the input terminal of the clipping unit 513, a second end of the eleventh resistor R11 and a first end of the twelfth resistor R12 are commonly connected to a first terminal of the output terminal of the clipping unit 513, a first end of the thirteenth resistor R13 is a first terminal of the input terminal of the clipping unit 513, a second end of the thirteenth resistor R13 and a first end of the fourteenth resistor R14 are commonly connected to a second terminal of the output terminal of the clipping unit 513, and a second end of the twelfth resistor R12 and a second end of the fourteenth resistor R14 are commonly connected to ground.
Referring to fig. 6, in an embodiment, the first rfi filtering unit 514 includes a thirteenth capacitor C13 and a fourteenth capacitor C14, a first terminal of the thirteenth capacitor C13 is connected to the first terminal of the output terminal of the clipping unit 513, a first terminal of the fourteenth capacitor C14 is connected to the second terminal of the output terminal of the clipping unit 513, and a second terminal of the thirteenth capacitor C13 and a second terminal of the fourteenth capacitor C14 are grounded.
Referring to fig. 6, in one embodiment, the differential pair internal capacitance unit 515 includes a fifteenth capacitance C15, and in other embodiments, the differential pair internal capacitance unit 515 may include capacitances connected in parallel or in series.
Referring to fig. 6, in an embodiment, the second dc blocking unit 516 includes a sixteenth capacitor C16 and a seventeenth capacitor C17, a first terminal of the sixteenth capacitor C16 is connected to the first terminal of the output terminal of the clipping unit 513, a second terminal of the sixteenth capacitor C16 is connected to the sampling module 600, a first terminal of the seventeenth capacitor C17 is connected to the second terminal of the output terminal of the clipping unit 513, and a second terminal of the seventeenth capacitor C17 is connected to the sampling module 600.
Referring to fig. 7, in an embodiment, the audio signal sampling module further includes an analog microphone access module 800, the analog microphone access module 800 is connected to the analog microphone module 200, and the analog microphone access module 800 is configured to acquire the second audio signal and transmit the second audio signal to the sampling module 600.
Referring to fig. 8, in order to facilitate understanding of the structure of the analog microphone access module 800, the analog microphone access module 800 is taken as an example in the present embodiment. The analog microphone access module 800 includes: a filter unit 811, a low pass filter unit 812, a second rfi filtering unit 813, a dc BIAS unit 814, a buffer unit 815 and a third dc blocking unit 816, wherein a first end of the filter unit 811 is externally connected to a BIAS voltage MIC-BIAS, a second end of the filter unit 811 is grounded, a first end of the low pass filter unit 812 is connected to the positive electrode of the analog microphone module 200, a second end of the low pass filter unit 812 is connected to the negative electrode of the analog microphone module 200, a first input end of the second rfi filtering unit 813 is connected to the positive electrode of the analog microphone module 200, a second input end of the second rfi filtering unit 813 is connected to the negative electrode of the analog microphone module 200, a power supply end of the dc BIAS unit 814 is connected to the first end of the filter unit 811 and the BIAS voltage MIC-BIAS, a ground end of the dc BIAS unit 814 is grounded, a first output end of the dc BIAS unit 814 is connected to the positive electrode of the analog microphone module 200, a second output end of the dc offset unit 814 is connected to a negative electrode of the analog microphone module 200, a first input end of the buffer unit 815 is connected to a positive electrode of the analog microphone module 200 and a first output end of the dc offset unit 814, a second input end of the buffer unit 815 is connected to a negative electrode of the analog microphone module 200 and a second output end of the dc offset unit 814, a first input end of the third dc blocking unit 816 is connected to a first terminal of a first differential input end of the sampling module 600 and a first output end of the buffer unit 815, and a second input end of the third dc blocking unit 816 is connected to a second terminal of a second differential input end of the sampling module 600 and a second output end of the buffer unit 815; the filtering unit 811 is configured to filter the BIAS voltage MIC-BIAS and output the analog microphone module 200; the low-pass filtering unit 812 is configured to filter out high-frequency interference components of the second audio signal; the second rfi filtering unit 813 is configured to filter out the rfi component of the second audio signal; the dc bias unit 814 is configured to provide a dc bias for the analog microphone module 200; the buffer unit 815 is configured to buffer a current surge caused by the dc bias unit 814; and the third dc blocking unit 816 is configured to block the dc component of the second audio signal and output the dc component to the sampling module 600.
Referring to fig. 9, in an embodiment, the filtering unit 811 includes an eighteenth capacitor C18 and a nineteenth capacitor C19, a first terminal of the eighteenth capacitor C18 and a first terminal of the nineteenth capacitor C19 are connected to the BIAS voltage MIC-BIAS, and a second terminal of the eighteenth capacitor C18 and a second terminal of the nineteenth capacitor C19 are commonly connected to ground.
Referring to fig. 9, in an embodiment, the low pass filter unit 812 includes a nineteenth resistor R19 and a twentieth capacitor C20, a first end of the nineteenth resistor R19 is connected to a negative electrode of the analog microphone module 200, a first end of the twentieth capacitor C20 is connected to a positive electrode of the analog microphone module 200, and a second end of the nineteenth resistor R19 is connected to a second end of the twentieth capacitor C20.
Referring to fig. 9, in an embodiment, the second rfi filtering unit 813 includes a twenty-first capacitor C21 and a twenty-second capacitor C22, a first end of the twenty-first capacitor C21 is connected to the positive electrode of the analog microphone module 200, a first end of the twenty-second capacitor C22 is connected to the negative electrode of the analog microphone module 200, and a second end of the twenty-first capacitor C21 and a second end of the twenty-second capacitor C22 are commonly connected to ground.
Referring to fig. 9, in an embodiment, the dc bias unit 814 includes a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18 and a tenth capacitor C10, a first end of the fifteenth resistor R15 is a power supply end of the dc bias unit 814, a second end of the fifteenth resistor R15 is connected to a first end of the tenth capacitor C10 and a first end of the sixteenth resistor R16, a second end of the sixteenth resistor R16 is a first output end of the dc bias unit 814, a first end of the seventeenth resistor R17 is a second output end of the dc bias unit 814, a second end of the seventeenth resistor R17 is connected to a first end of the eighteenth resistor R18 and a second end of the tenth capacitor C10, and a second end of the eighteenth resistor R18 is a ground end of the dc bias unit 814.
Referring to fig. 9, in an embodiment, the buffer unit 815 includes a seventh magnetic bead FB7 and an eighth magnetic bead FB8, a first end of the seventh magnetic bead FB7 is a first input end of the buffer unit 815, a second end of the seventh magnetic bead FB7 is a first output end of the buffer unit 815, a first end of the eighth magnetic bead FB8 is a second input end of the buffer unit 815, and a second end of the eighth magnetic bead FB8 is a second output end of the buffer unit 815.
Referring to fig. 9, in an embodiment, the third dc blocking unit 816 includes a twenty-third capacitor C23 and a twenty-fourth capacitor C24, a first terminal of the twenty-third capacitor C23 is a first input terminal of the third dc blocking unit 816, and a first terminal of the twenty-fourth capacitor C24 is a second input terminal of the third dc blocking unit 816.
Referring to fig. 9, in an embodiment, the anti-static unit 817 is further included, and the anti-static unit 817 includes a first bi-directional transient suppression diode D1 and a second bi-directional transient suppression diode D2, a first end of the first bi-directional transient suppression diode D1 is connected to the anode of the analog microphone module 200, a first end of the second bi-directional transient suppression diode D2 is connected to the cathode of the analog microphone module 200, a second end of the first bi-directional transient suppression diode D1 is grounded, and a second end of the second bi-directional transient suppression diode D2 is grounded.
The utility model provides a second aspect of the embodiment provides a pronunciation stereo set pickup apparatus, a serial communication port, include: loudspeaker 100 and the pronunciation stereo set pickup circuit as the first aspect of the embodiment of the utility model discloses.
The above description is only exemplary of the present invention and should not be construed as limiting the present invention, and any modifications, equivalents and improvements made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. The utility model provides a pronunciation stereo set pickup circuit, is connected with loudspeaker, its characterized in that, pronunciation stereo set pickup circuit includes:
a control module;
the digital power amplifier module is connected with the loudspeaker and the control module and used for converting a first signal output by the control module into a first audio signal, transmitting the first audio signal to the loudspeaker, generating a feedback signal according to the first audio signal and transmitting the feedback signal to the control module;
the echo acquisition module is connected with the input end of the loudspeaker and the output end of the digital power amplifier module and is used for acquiring the first audio signal;
the analog microphone module is used for collecting external sound and converting the external sound into a second audio signal, wherein the external sound comprises a voice instruction and a first audio frequency played by the loudspeaker according to the first audio signal;
the sampling module is connected with the control module, the analog microphone module and the echo acquisition module, and is used for converting a first audio signal acquired by the echo acquisition module into a first digital signal, converting a second audio signal into a second digital signal and transmitting the first digital signal and the second digital signal to the control module; and
the digital microphone module is connected with the control module and is used for acquiring the outside sound, converting the outside sound into a third digital signal and transmitting the third digital signal to the control module;
the control module performs noise elimination processing on the first digital signal and the second digital signal according to a first preset rule to obtain the voice command, or performs noise elimination processing on the feedback signal and the third digital signal according to a second preset rule to obtain the voice command.
2. The voice sound pickup circuit of claim 1, wherein the sampling module comprises: each pair of differential signal input ends of the analog-to-digital conversion chip is connected with the analog microphone module and the loudspeaker, a bus end of the analog-to-digital conversion chip is connected with a bus end of the control module, a bus address configuration end of the analog-to-digital conversion chip is connected with a second end of the first resistor and a first end of the second resistor, a second end of the second resistor is grounded, a first end of the first resistor is externally connected with a direct current voltage with a first end of the first magnetic bead, a second end of the first magnetic bead is connected with a first end of the first capacitor and a first end of the second magnetic bead, a second end of the first capacitor is grounded, and a second end of the second magnetic bead is connected with a first end of the second capacitor and an analog power supply end of the analog-to-digital conversion chip, the second end of the second capacitor is grounded, and the voltage stabilizing end of the analog-to-digital conversion chip is grounded through the third capacitor.
3. The voice sound pickup circuit according to claim 1, wherein the digital power amplifier module comprises: the signal input and output end of the digital power amplifier chip is connected with the control module, a first terminal of a first differential output opposite end of the digital power amplifier chip is connected with a first end of the third magnetic bead, a second terminal of the first differential output opposite end of the digital power amplifier chip is connected with a first end of the fourth magnetic bead, a second end of the third magnetic bead and a second end of the fourth magnetic bead are connected with a first end of the third resistor in a common mode, a second end of the third resistor is connected with the anode of the horn, a first terminal of a second differential output opposite end of the digital power amplifier chip is connected with a first end of the fifth magnetic bead, a second terminal of a second differential output opposite end of the digital power amplifier chip is connected with a first end of the sixth magnetic bead, the second end of the fifth magnetic bead and the second end of the sixth magnetic bead are connected to the first end of the fourth resistor in common, and the second end of the fourth resistor is connected to the negative electrode of the horn.
4. The voice sound pickup circuit of claim 1, wherein the echo acquisition module comprises:
the first DC blocking unit is connected with the loudspeaker and is used for isolating a DC component in the first audio signal;
the input end of the multi-order low-pass filter unit is connected with the output end of the first stopping unit, and the multi-order low-pass filter unit is used for filtering high-frequency interference components in the first audio signal;
the input end of the amplitude limiting unit is connected with the output end of the multi-order low-pass filtering unit, the ground end of the amplitude limiting unit is grounded, and the amplitude limiting unit is used for controlling the output amplitude of the first audio signal;
the input end of the first radio frequency interference filtering unit is connected with the output end of the amplitude limiting unit, the output end of the first radio frequency interference filtering unit is grounded, and the first radio frequency interference filtering unit is used for filtering radio frequency interference components in the first audio signal;
the differential pair internal capacitance unit is connected with the amplitude limiting unit and is used for filtering out differential pair internal interference components of the first audio signal; and
and the second blocking unit is connected with the amplitude limiting unit and the sampling module and is used for isolating the direct current component of the first audio signal again.
5. The audio pick-up circuit of claim 4, wherein the multi-step low-pass filter unit comprises a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, and a ninth capacitor, a first end of the fifth resistor is connected to the first terminal of the output terminal of the first dc-blocking unit, a second end of the fifth resistor is connected to the first end of the sixth resistor and the first end of the fourth capacitor, a second end of the sixth resistor is connected to the first end of the seventh resistor and the first end of the fifth capacitor, a second end of the seventh resistor and the first end of the sixth capacitor are connected together as the first terminal of the output terminal of the multi-step low-pass filter unit, and a first end of the eighth resistor is connected to the second terminal of the output terminal of the first dc-blocking unit, the second end of the eighth resistor is connected to the first end of the ninth resistor and the first end of the seventh capacitor, the second end of the ninth resistor is connected to the first end of the tenth resistor and the first end of the eighth capacitor, the second end of the tenth resistor and the first end of the ninth capacitor are connected in common to serve as the second terminal of the output end of the multi-stage low-pass filter unit, and the second end of the fourth capacitor, the second end of the fifth capacitor, the second end of the sixth capacitor, the second end of the seventh capacitor, the second end of the eighth capacitor and the second end of the ninth capacitor are connected in common to ground.
6. The audio pick-up circuit of claim 4, wherein the amplitude limiting unit comprises an eleventh resistor, a twelfth resistor, a thirteenth resistor and a fourteenth resistor, a first end of the eleventh resistor is a first terminal of the input terminal of the amplitude limiting unit, a second end of the eleventh resistor and a first end of the twelfth resistor are commonly connected to a first terminal of the output terminal of the amplitude limiting unit, a first end of the thirteenth resistor is a first terminal of the input terminal of the amplitude limiting unit, a second end of the thirteenth resistor and a first end of the fourteenth resistor are commonly connected to a second terminal of the output terminal of the amplitude limiting unit, and a second end of the twelfth resistor and a second end of the fourteenth resistor are commonly connected to ground.
7. The voice sound pickup circuit according to any one of claims 1 to 6, further comprising an analog microphone access module, wherein the analog microphone access module is connected to the analog microphone module and the sampling module, and the analog microphone access module is configured to collect the second audio signal and transmit the second audio signal to the sampling module.
8. The voice sound pickup circuit of claim 7, wherein the analog microphone access module comprises:
the first end of the filtering unit is externally connected with a bias voltage, the second end of the filtering unit is grounded, and the filtering unit is used for filtering the bias voltage and outputting the filtered bias voltage to the analog microphone module;
the first end of the low-pass filtering unit is connected with the anode of the analog microphone module, the second end of the low-pass filtering unit is connected with the cathode of the analog microphone module, and the low-pass filtering unit is used for filtering out high-frequency interference components of the second audio signal;
a first input end of the second radio frequency interference filtering unit is connected with the anode of the analog microphone module, a second input end of the second radio frequency interference filtering unit is connected with the cathode of the analog microphone module, and the second radio frequency interference filtering unit is used for filtering radio frequency interference components of the second audio signal;
a power supply terminal of the dc bias unit is connected to the first terminal of the filter unit and the bias voltage, a ground terminal of the dc bias unit is grounded, a first output terminal of the dc bias unit is connected to the anode of the analog microphone module, a second output terminal of the dc bias unit is connected to the cathode of the analog microphone module, and the dc bias unit is configured to provide dc bias for the analog microphone module;
a first input end of the buffer unit is connected with a positive electrode of the analog microphone module and a first output end of the direct current bias unit, a second input end of the buffer unit is connected with a negative electrode of the analog microphone module and a second output end of the direct current bias unit, and the buffer unit is used for buffering current impact brought by the direct current bias unit; and
and a third blocking unit, wherein a first input end of the third blocking unit is connected with a first output end of the buffer unit and a first terminal of a first differential input end of the sampling module, a second input end of the third blocking unit is connected with a second output end of the buffer unit and a second terminal of the first differential input end of the sampling module, and the third blocking unit is used for isolating a direct current component of the second audio signal and then outputting the second audio signal to the sampling module.
9. The audio pick-up circuit of claim 8, wherein the dc bias unit comprises a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor and a tenth capacitor, a first terminal of the fifteenth resistor is a power supply terminal of the dc bias unit, a second terminal of the fifteenth resistor is connected to a first terminal of the tenth capacitor and a first terminal of the sixteenth resistor, a second terminal of the sixteenth resistor is a first output terminal of the dc bias unit, a first terminal of the seventeenth resistor is a second output terminal of the dc bias unit, a second terminal of the seventeenth resistor is connected to a first terminal of the eighteenth resistor and a second terminal of the tenth capacitor, and a second terminal of the eighteenth resistor is a ground terminal of the dc bias unit.
10. A voice sound pickup apparatus, comprising: a speaker and a voice acoustic pick-up circuit as claimed in any one of claims 1 to 9.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920880978.XU CN209845280U (en) | 2019-06-12 | 2019-06-12 | Voice sound pickup circuit and device |
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| CN201920880978.XU CN209845280U (en) | 2019-06-12 | 2019-06-12 | Voice sound pickup circuit and device |
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| CN209845280U true CN209845280U (en) | 2019-12-24 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110324759A (en) * | 2019-06-12 | 2019-10-11 | 深圳市金锐显数码科技有限公司 | Voice sound equipment pickup circuit and device |
| CN110830749A (en) * | 2019-12-27 | 2020-02-21 | 深圳市创维群欣安防科技股份有限公司 | Video call echo cancellation circuit and method and conference panel |
| CN112086101A (en) * | 2020-08-19 | 2020-12-15 | 广州亚美智造科技有限公司 | Noise reduction circuit, voice recognition module and electronic equipment |
| CN113839685A (en) * | 2021-09-28 | 2021-12-24 | 惠州市讯扬科技有限公司 | Digital-analog signal circuit board and landline telephone |
-
2019
- 2019-06-12 CN CN201920880978.XU patent/CN209845280U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110324759A (en) * | 2019-06-12 | 2019-10-11 | 深圳市金锐显数码科技有限公司 | Voice sound equipment pickup circuit and device |
| CN110830749A (en) * | 2019-12-27 | 2020-02-21 | 深圳市创维群欣安防科技股份有限公司 | Video call echo cancellation circuit and method and conference panel |
| CN112086101A (en) * | 2020-08-19 | 2020-12-15 | 广州亚美智造科技有限公司 | Noise reduction circuit, voice recognition module and electronic equipment |
| CN113839685A (en) * | 2021-09-28 | 2021-12-24 | 惠州市讯扬科技有限公司 | Digital-analog signal circuit board and landline telephone |
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