Audio amplification and control circuit system

Abstract

The utility model relates to an audio amplification and control circuit system, which belongs to the technical field of electronic communication and comprises a first microphone audio and three-channel voice amplification module, a first channel selection module, a second channel selection module, a third channel selection module, a fourth channel selection module, a first band-pass module and a first low-pass module. A modulation and emission module, a receiving and demodulation module and a voice output module, the first microphone audio and three-channel voice amplification module, the first channel selection module, the first band-pass module, the second channel selection module, the third channel selection module, the modulation and emission module, the receiving and demodulation module, the first low-pass module, the fourth channel selection module and the voice output module are mutually connected. According to the utility model, the purpose of multi-channel audio selection application is realized in audio amplification and control.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic communications, and in particular to an audio amplification and control circuit system. Background Art

[0002] With the continuous development of science and technology, more and more audio applications have emerged to meet the needs of people's production and life, and corresponding audio equipment has also become popular. In actual hardware audio implementation, a single microphone signal is usually collected and amplified to the speaker for amplification, which cannot better solve the user's multi-channel audio application. Utility Model Content

[0003] In view of this, it is necessary to provide an audio amplification and control circuit system to solve the technical problem of realizing multi-channel audio selection application in audio amplification and control.

[0004] In order to solve the above technical problems, the utility model provides an audio amplification and control circuit system, including: a first microphone audio and three-channel voice amplification module, a first channel selection module, a second channel selection module, a third channel selection module, a fourth channel selection module, a first bandpass module, a first low-pass module, a modulation and transmission module, a receiving and demodulation module, and a voice output module;

[0005] The output end of the first microphone audio and three-channel voice amplification module is connected to the input end of the first channel selection module, the output end of the first channel selection module is connected to the input end of the first bandpass module, the output end of the first bandpass module is connected to the input end of the second channel selection module, the output end of the second channel selection module is connected to the input end of the third channel selection module, the output end of the third channel selection module is connected to the input end of the modulation and transmission module, the output end of the modulation and transmission module is connected to the input end of the receiving and demodulation module, the output end of the receiving and demodulation module is connected to the input end of the first low-pass module, the output end of the first low-pass module is connected to the input end of the fourth channel selection module, and the output end of the fourth channel selection module is connected to the voice output module.

[0006] In a possible implementation, the system further includes: a second microphone audio and three-channel voice amplification module, a second low-pass module and a fifth channel selection module;

[0007] The output end of the second microphone audio and three-channel voice amplification module is connected to the input end of the fifth channel selection module, the output end of the fifth channel selection module is connected to the input end of the second low-pass module, and the output end of the second low-pass module is connected to the input end of the third channel selection module.

[0008] In a possible implementation, the system further includes: a digitally controlled volume adjustment module, a recording module, a second bandpass module, and a sixth channel selection module;

[0009] The output end of the second channel selection module is also connected to the input end of the sixth channel selection module, the output end of the sixth channel selection module is connected to the input end of the second bandpass module, the output end of the second bandpass module is connected to the input end of the digital control volume adjustment module, and the output end of the digital control volume adjustment module is connected to the recording module.

[0010] In a possible implementation, the system further includes: a seventh channel selection module and a headphone output module;

[0011] The output end of the digital control volume adjustment module is also connected to the input end of the seventh channel selection module, and the output end of the seventh channel selection module is connected to the headphone output module.

[0012] In a possible implementation, the system further includes: a speaker output module;

[0013] The output end of the seventh channel selection module is also connected to the speaker output module.

[0014] In a possible implementation, the digital control volume adjustment module uses a chip model DS1867.

[0015] In a possible implementation manner, the filter chip model used by the first bandpass module and the second bandpass module is MAX274.

[0016] In a possible implementation manner, the audio transformer model of the first channel selection module is HR220803.

[0017] In a possible implementation manner, the first low-pass module adopts a Sallen-key active filter topology structure.

[0018] In a possible implementation, the first channel selection module uses a chip of type 74HC4053D.

[0019] The beneficial effect of the technical solution of the utility model is as follows: the audio amplification and control circuit system provided by the utility model comprises: a first microphone audio and three-channel voice amplification module, a first channel selection module, a second channel selection module, a third channel selection module, a fourth channel selection module, a first bandpass module, a first low-pass module, a modulation and transmission module, a receiving and demodulation module, and a voice output module. The output end of the first microphone audio and three-channel voice amplification module is connected to the input end of the first channel selection module, the output end of the first channel selection module is connected to the input end of the first bandpass module, the output end of the first bandpass module is connected to the input end of the second channel selection module, the output end of the second channel selection module is connected to the input end of the third channel selection module, the output end of the third channel selection module is connected to the input end of the modulation and transmission module, the output end of the modulation and transmission module is connected to the input end of the receiving and demodulation module, the output end of the receiving and demodulation module is connected to the input end of the first low-pass module, the output end of the first low-pass module is connected to the input end of the fourth channel selection module, and the output end of the fourth channel selection module is connected to the voice output module. Furthermore, the channel selection module proposed in the present invention can achieve the purpose of multi-channel audio selection application in audio amplification and control, and can be used in different scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic structural diagram of a first embodiment of an audio amplification and control circuit system provided by the utility model;

[0021] Figure 2 A schematic structural diagram of a second embodiment of the audio amplification and control circuit system provided by the utility model;

[0022] Figure 3 A schematic structural diagram of a third embodiment of the audio amplification and control circuit system provided by the utility model;

[0023] Figure 4 A schematic structural diagram of a fourth embodiment of the audio amplification and control circuit system provided by the utility model;

[0024] Figure 5 A schematic structural diagram of a fifth embodiment of the audio amplification and control circuit system provided by the utility model;

[0025] Figure 6 for Figure 4 A circuit diagram of an embodiment of a digitally controlled volume adjustment module;

[0026] Figure 7 for Figure 1 A circuit diagram of an embodiment of the first bandpass module;

[0027] Figure 8 for Figure 1 A circuit diagram of an embodiment of a first low-pass model;

[0028] Fig. 9 for Figure 2 A circuit diagram of an embodiment of the fifth channel selection module. DETAILED DESCRIPTION

[0029] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0030] Figure 1 The first embodiment of the audio amplification and control circuit system 100 provided by the utility model includes: a first microphone audio and three-channel voice amplification module 101, a first channel selection module 102, a second channel selection module 104, a third channel selection module 105, a fourth channel selection module 109, a first bandpass module 103, a first low-pass module 108, a modulation and transmission module 106, a receiving and demodulation module 107, and a voice output module 110;

[0031] The output end of the first microphone audio and three-channel voice amplification module 101 is connected to the input end of the first channel selection module 102, the output end of the first channel selection module 102 is connected to the input end of the first bandpass module 103, the output end of the first bandpass module 103 is connected to the input end of the second channel selection module 104, the output end of the second channel selection module 104 is connected to the input end of the third channel selection module 105, the output end of the third channel selection module 105 is connected to the input end of the modulation and transmission module 106, the output end of the modulation and transmission module 106 is connected to the input end of the receiving and demodulation module 107, the output end of the receiving and demodulation module 107 is connected to the input end of the first low-pass module 108, the output end of the first low-pass module 108 is connected to the input end of the fourth channel selection module 109, and the output end of the fourth channel selection module 109 is connected to the voice output module 110.

[0032] It can be understood that the audio amplification and control circuit system provided by the utility model includes: a first microphone audio and three-channel voice amplification module 101, a first channel selection module 102, a second channel selection module 104, a third channel selection module 105, a fourth channel selection module 109, a first bandpass module 103, a first low-pass module 108, a modulation and transmission module 106, a receiving and demodulation module 107, and a voice output module 110. The output end of the first microphone audio and three-channel voice amplification module 101 is connected to the input end of the first channel selection module 102, and the output end of the first channel selection module 102 is connected to the first bandpass module 103. The input end of the first bandpass module 103 is connected to the input end of the second channel selection module 104, the output end of the second channel selection module 104 is connected to the input end of the third channel selection module 105, the output end of the third channel selection module 105 is connected to the input end of the modulation and transmission module 106, the output end of the modulation and transmission module 106 is connected to the input end of the receiving and demodulation module 107, the output end of the receiving and demodulation module 107 is connected to the input end of the first low-pass module 108, the output end of the first low-pass module 108 is connected to the input end of the fourth channel selection module 109, and the output end of the fourth channel selection module 109 is connected to the voice output module 110. Further, the channel selection module proposed in the utility model can realize the purpose of multi-channel audio selection application in audio amplification and control, and can be used in different scenarios.

[0033] Figure 2 The second embodiment of the structure diagram of the audio amplification and control circuit system provided by the utility model includes:

[0034] A second microphone audio and three-channel voice amplification module 201, a second low-pass module 203 and a fifth channel selection module 202;

[0035] The output end of the second microphone audio and three-channel voice amplification module 201 is connected to the input end of the fifth channel selection module 202, the output end of the fifth channel selection module 202 is connected to the input end of the second low-pass module 203, and the output end of the second low-pass module 203 is connected to the input end of the third channel selection module 104.

[0036] Figure 3 The third embodiment of the structure diagram of the audio amplification and control circuit system provided by the utility model includes: a digital control volume adjustment module 303, a recording module 304, a second bandpass module 302 and a sixth channel selection module 301;

[0037] The output end of the second channel selection module 104 is also connected to the input end of the sixth channel selection module 301, the output end of the sixth channel selection module 301 is connected to the input end of the second bandpass module 302, the output end of the second bandpass module 302 is connected to the input end of the digital control volume adjustment module 303, and the output end of the digital control volume adjustment module 303 is connected to the recording module 304.

[0038] Figure 4 The fourth embodiment of the structure diagram of the audio amplification and control circuit system provided by the utility model includes: a seventh channel selection module 401 and an earphone output module 402;

[0039] The output end of the digital control volume adjustment module 303 is also connected to the input end of the seventh channel selection module 401 , and the output end of the seventh channel selection module 401 is connected to the earphone output module 402 .

[0040] Figure 5 The fifth embodiment of the structure diagram of the audio amplification and control circuit system provided by the utility model includes: a speaker output module 501;

[0041] The output end of the seventh channel selection module 401 is also connected to the speaker output module 501 .

[0042] Figure 6 for Figure 4 The circuit diagram of an embodiment of the digital control volume adjustment module 303 includes:

[0043] The chip model used by the digital control volume adjustment module 303 is DS1867.

[0044] It can be understood that the digital control volume adjustment module 303 preferably uses the DS1867 chip. This chip has 2 independent digital control potentiometers inside, and has EEPOM function. It has volume memory function after power failure and is very suitable for volume potentiometer. The amplified audio signal is connected to pins 2 and 11 of the digital control volume chip U7, and pins 3 and 10 of the digital control volume chip U7 are grounded.

[0045] Pins 5, 6, and 8 of the digital volume chip U7 are connected to the control unit. The control signal adjusts the volume of W1 through a 3-wire timing sequence. Pin 4 of the digital volume chip U7 outputs the audio signal after adjusting the volume. After connecting C63, the other end of C62 is connected to the recording function port.

[0046] Pins 5, 6, and 8 of the digital control volume chip U7 are connected to the control unit. The control signal adjusts the volume of W0 through a 3-wire timing sequence. Pin 12 of the digital control volume chip U7 outputs the audio signal after the volume is adjusted. After connecting C62, the other end of C62 is connected to pin 1 of the noise reduction selection channel U4B.

[0047] Pin 2 of the noise reduction selection channel U4B is connected to R138 and C60 in parallel, and pin 10 of U4B is connected to the control level. When the level is low, the voice noise reduction mode is selected to prevent noise when the speaker and headphones are not in use.

[0048] When pin 10 of the noise reduction selection channel U4B is at a high level, the audio signal is connected to pin 15 of U4B, and the volume-controlled audio signal is output to the speaker and headphones.

[0049] Pin 15 of the noise reduction selection channel U4B is connected to pins 3 and 6 of relay S1, the control level of relay S1 is connected to R140 and C70, the other end of C70 is grounded, R140 is connected to R142 in parallel with C78, ​​the other ends of R142 and C78 are grounded, R140 is connected to the b pole of Q4, the e pole is grounded, the C pole is connected to pin 8 of relay S1 and D1, and the 1 pin of relay S1 and the other end of D1 are connected to the 12V power supply together.

[0050] When the control level of relay S1 is low, pins 3 and 2 of relay S1 are connected, and the speaker outputs audio sound. At the same time, pins 5 and 6 of relay S1 are disconnected, and no audio sound is output from the earphone.

[0051] When the control level of relay S1 is high, pins 5 and 5 of relay S1 are connected, and the earphone outputs audio sound. At the same time, pins 2 and 3 of relay S1 are disconnected, and no audio sound is output by the speaker.

[0052] Relay S1 is preferably Omron G6J-2P, which has a long service life and reliable contact connection, and in particular, the signal isolation reaches more than 70dB to avoid crosstalk between the speaker and the earphone.

[0053] Figure 7 for Figure 1 A circuit diagram of an embodiment of the first bandpass module in the embodiment of the present invention comprises:

[0054] The filter chip model used by the first bandpass module 103 and the second bandpass module 302 is MAX274.

[0055] It is understandable that the first bandpass module 103 circuit of the utility model adopts the 8th order continuous time filter chip MAX274 of Maxim Company. The design scheme is simple and the circuit performance is stable. The commonly used circuit form is composed of RC elements plus operational amplifiers. The circuit is relatively easy to implement, but the calculation and adjustment of component parameters are difficult, especially when working in a high frequency state, the stray capacitance of the circuit has a significant impact on the transmission characteristics of the filter. This utility model circuit avoids the shortcomings of the traditional active filter design calculation process, the difficulty in adjusting parameters, etc.

[0056] The MAX274 chip active bandpass filter circuit is used. The audio signal is input from pin 2 of the chip. In order to use small resistors, R57, R58, and R61 form the A channel T-type network of the LPF, and R66, R67, and R73 form the A channel T-type network of the BPF. R60 and two groups of T-type resistor networks and the capacitors and resistors in the A channel 4 operational amplifiers inside the chip form a cascade integration circuit, which can provide low-pass and band-pass filter outputs at the same time.

[0057] The A channel filter output is connected to the B channel input through R82, and a cascade integration circuit is formed by R71, R77, R83 and the capacitors and resistors in the B channel 4 op amps inside the chip, providing both low-pass and band-pass filter outputs.

[0058] The B channel filter output is connected to the C channel input through R81. In order to use small resistors, R79, R84, and R85 form the C channel T-type network of the LPF, and R69, R72, and R74 form the C channel T-type network of the BPF. R78 and two sets of T-type resistor networks and the capacitors and resistors in the C channel 4 op amps inside the chip form a cascade integration circuit, which can provide low-pass and band-pass filter outputs at the same time.

[0059] The C channel filter output is connected to the D channel input through R76, and a cascade integration circuit is formed by R59, R63, R68 and the capacitors and resistors in the D channel 4 op amp inside the chip, providing low-pass and band-pass filter outputs at the same time.

[0060] The D channel filter output is connected to the op amp OPA2134 through C46, ​​and the op amp amplifies it by 3.2 times to output a bandpass 300-3.4KHz audio signal.

[0061] In some embodiments of the present invention, the audio transformer model of the first channel selection module 102 is HR220803.

[0062] exist Figure 8 for Figure 1 A circuit diagram of an embodiment of a first low-pass model in FIG. 1 , comprising:

[0063] The first low-pass module 108 adopts a Sallen-key active filter topology structure.

[0064] It is understandable that the first low-pass module 108 circuit of the utility model adopts a Sallen-Key active filter topology structure. The second-order structure of the Butterworth filter is adopted, which has a flat passband and a steep stopband characteristic. This circuit uses an operational amplifier configured in a voltage follower mode, and the circuit has low cost, good stability, and excellent performance, meeting the technical index requirements of this system.

[0065] The audio signal is connected to R37 through R36, and then to C44. The other end of C44 is connected to the ground. R37 is also connected to the 3rd pin of the OPA2134 operational amplifier chip. After R36 is connected to C42, the other end of C42 is connected to the 1st pin of the operational amplifier. The 2nd pin of the operational amplifier is connected to the 1st pin to form a voltage follower. The 1st pin of the operational amplifier is connected to C43 to output an audio frequency lower than 25.6KHz.

[0066] Fig. 9 for Figure 2 The circuit diagram of an embodiment of the fifth channel selection module 202 includes:

[0067] The chip model used by the first channel selection module 102 is 74HC4053D.

[0068] It can be understood that, in the first channel selection module 102, the voice channel CH2 adopts the HR220803 audio transformer, the 600 ohm differential audio signal input, the T6 transformer is connected to R62, and then connected to the 2nd pin reverse input terminal of the operational amplifier OPA2134, the 3rd pin of the operational amplifier is connected to R61, and the other end of R61 is grounded, R63 and R64 are connected in parallel between the 1st and 2nd pins of the operational amplifier, and this operational amplifier is designed to amplify the audio signal by 1.9 times, and the 1st pin of the operational amplifier is connected to the 13th pin of the channel selection module U8A.

[0069] Voice channel CH3 also uses HR220803 audio transformer, 600 ohm differential audio signal input, T7 transformer connected to R66, connected to the 6-pin reverse input terminal of operational amplifier OPA2134, the 5-pin positive terminal of the operational amplifier connected to R65, the other end of R65 is grounded, R67 and R68 are connected in parallel between the 6-pin and 7-pin of the operational amplifier, this operational amplifier is designed to amplify the audio signal by 1.7 times, and the 7-pin of the operational amplifier is connected to the 12-pin of the channel selection module U8A.

[0070] Pin 11 of the audio channel selection module U8A is connected to the control level. When the level is low, the audio signal amplified by the voice CH3 channel is selected. After the pin 14 of U8A is connected to C67, the audio signal amplified by the voice CH3 channel is output.

[0071] Pin 11 of the audio channel selection module U8A selects the audio signal amplified by the voice CH2 channel when the level is high. After pin 14 of U8A is connected to C67, the audio signal amplified by the voice CH2 channel is output.

[0072] The above are only preferred specific implementation methods of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present invention should be covered within the protection scope of the present invention.

Claims

1. An audio amplification and control circuit system, characterized in that: include: A first microphone audio and three-channel voice amplification module, a first channel selection module, a second channel selection module, a third channel selection module, a fourth channel selection module, a first bandpass module, a first low-pass module, a modulation and transmission module, a reception and demodulation module, and a voice output module; The output end of the first microphone audio and three-channel voice amplification module is connected to the input end of the first channel selection module, the output end of the first channel selection module is connected to the input end of the first bandpass module, the output end of the first bandpass module is connected to the input end of the second channel selection module, the output end of the second channel selection module is connected to the input end of the third channel selection module, the output end of the third channel selection module is connected to the input end of the modulation and transmission module, the output end of the modulation and transmission module is connected to the input end of the receiving and demodulation module, the output end of the receiving and demodulation module is connected to the input end of the first low-pass module, the output end of the first low-pass module is connected to the input end of the fourth channel selection module, and the output end of the fourth channel selection module is connected to the voice output module.

2. The audio amplification and control circuit system according to claim 1, characterized in that: The system further includes: a second microphone audio and three-channel voice amplification module, a second low-pass module and a fifth channel selection module; The output end of the second microphone audio and three-channel voice amplification module is connected to the input end of the fifth channel selection module, the output end of the fifth channel selection module is connected to the input end of the second low-pass module, and the output end of the second low-pass module is connected to the input end of the third channel selection module.

3. The audio amplification and control circuit system according to claim 2, characterized in that: The system further includes: a digitally controlled volume adjustment module, a recording module, a second bandpass module and a sixth channel selection module; The output end of the second channel selection module is also connected to the input end of the sixth channel selection module, the output end of the sixth channel selection module is connected to the input end of the second bandpass module, the output end of the second bandpass module is connected to the input end of the digital control volume adjustment module, and the output end of the digital control volume adjustment module is connected to the recording module.

4. The audio amplification and control circuit system according to claim 3, characterized in that: The system further includes: a seventh channel selection module and a headphone output module; The output end of the digital control volume adjustment module is also connected to the input end of the seventh channel selection module, and the output end of the seventh channel selection module is connected to the headphone output module.

5. The audio amplification and control circuit system according to claim 4, characterized in that: The system further includes: a speaker output module; The output end of the seventh channel selection module is also connected to the speaker output module.

6. The audio amplification and control circuit system according to claim 4, characterized in that: The chip model used by the digital control volume adjustment module is DS1867.

7. The audio amplification and control circuit system according to claim 3, characterized in that: The filter chip model used by the first bandpass module and the second bandpass module is MAX274.

8. The audio amplification and control circuit system according to claim 1, characterized in that: The audio transformer model of the first channel selection module is HR220803.

9. The audio amplification and control circuit system according to claim 1, characterized in that: The first low-pass module adopts Sallen-key's active filter topology.

10. The audio amplification and control circuit system according to claim 1, characterized in that: The chip model used by the first channel selection module is 74HC4053D.

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