Massage music sofa control system based on sound channel delay and sound intensity balance

Abstract

The invention relates to the technical field of sound equipment, and particularly discloses a massage music sofa control system based on sound channel delay and sound intensity balance, which comprises a Bluetooth main control circuit used for completing a Bluetooth audio protocol, controlling playing of Bluetooth songs, communicating with a vibration massage circuit and controlling vibration massage to realize output of various massage waveforms, a control signal of the hand controller is received and a corresponding control task is completed; the vibration massage circuit is used for generating various massage vibration waveforms and driving a vibrator after power amplification so as to complete massage of various vibration waveforms; the audio signals are output after being subjected to sound effect processing and power amplification through the audio power amplifier circuit; and the hand controller is used for adjusting the volume, high pitch, low pitch, left-right balance and vibration amplitude of the system through a knob potentiometer, and switching different sound effect modes and vibration modes through buttons. By adjusting the sound intensity of the left sound channel and the right sound channel and compensating the sound channel delay, high-fidelity music can be reproduced when a user sits at different positions.

Description

Technical Field

[0001] The invention relates to the technical field of electronic acoustics, and in particular to a massage music sofa control system based on sound channel delay and sound intensity balance. Background Art

[0002] The music sofa is a smart furniture that can play music. After searching, the Chinese invention patent application with patent application number CN202211579205.0 discloses a music sofa control method, including: monitoring the pressure data on the music sofa; when the pressure data is greater than the preset pressure threshold, the music sofa area is identified as a user, and the seating result of the music sofa is obtained; when the seating result indicates that the user is seated on the music sofa, the music is controlled to play. This application monitors the pressure data on the music sofa, and when the pressure data is greater than the preset pressure threshold, the music sofa area is identified as a user, and the seating result of the music sofa is obtained; when the seating result indicates that the user is seated on the music sofa, the music is controlled to play. As long as the user sits on the music sofa, the effect of driving the music sofa to play music can be achieved, without the user having to find a remote control to drive the music sofa to play music, thereby improving the convenience of controlling the music sofa to play music.

[0003] However, today's music sofas are generally divided into single sofas, double sofas, and triple sofas. For a single sofa, because the left and right stereo speakers are placed in symmetrical positions on the left and right of the single seat, there is no problem of inconsistent sound intensity between the left and right channels. However, in double sofas and multi-person sofas, because the left and right speakers can only be placed on the left and right sides of the sofa, when a person sits on the left side of the sofa, the sound intensity on the left side is obviously greater than that on the right side. Similarly, when sitting on the right side of the sofa, the sound intensity on the right side is obviously greater than that on the left. There is a problem of stereo asymmetry on both sides, and the user's listening experience will deteriorate sharply.

[0004] The traditional solution is to match the left and right balance by adjusting the sound intensity of the left and right channels. However, this method has certain limitations: because when people deviate from the center position of the left and right speakers, the distance not only affects the sound intensity, but also causes a certain phase difference between the left and right channels. This phase difference usually makes the listener feel that the sound field has become wider, but the sense of direction of the sound has become worse. If you only change the sound intensity of the left and right channels without compensating for the sound delay, you cannot reproduce the original sound very well. Another problem is: if you simply adjust the sound intensity, the power of the side far away from the user often needs to be greatly increased to balance with the side close to the user, resulting in a significant increase in the power of the massage vibrator when massaging with the rhythm of the music. This will cause two problems: the vibrator has a risk of burning out due to excessive power; the user will also feel that the vibration is too strong and feel uncomfortable. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a massage music sofa control system based on channel delay and sound intensity equalization, which corrects the high-fidelity music reproduction when the user sits in different positions by adjusting the sound intensity of the left and right channels and compensating for the channel delay, aiming at the above-mentioned defects of the prior art.

[0006] To solve the above technical problem, the technical solution of the present invention is:

[0007] A massage music sofa control system based on channel delay and sound intensity equalization, comprising:

[0008] A Bluetooth main control circuit, which is used to complete the Bluetooth audio protocol, control the playback of Bluetooth songs, communicate with the vibration massage circuit, control the vibration massage to output a variety of massage waveforms, receive the control signal of the hand controller and complete the corresponding control tasks;

[0009] A vibration massage circuit, which is used to generate a variety of massage vibration waveforms, drive the vibrator after power amplification, and complete the massage of a variety of vibration waveforms;

[0010] An audio power amplifier circuit, and the audio signal is output after being subjected to sound effect processing and power amplification by the audio power amplifier circuit;

[0011] A hand controller, which is used to adjust the system volume, treble, bass, left and right balance, and vibration amplitude through a rotary potentiometer, and switch different sound effect modes and vibration modes through buttons.

[0012] Preferably, the Bluetooth main control circuit decodes the PCM data, opens a first-in-first-out FIFO buffer area in the RAM area, and the size of the buffer area determines the delay duration. The delay duration is adjusted by changing the buffer area duration. The calculation formula is T = buf_len / (SampleRate * channel * bit_per_sample / 8), where buf_len is the size of the opened buffer, SampleRate is the sampling rate, the sampling rate is fixed at 48K, channel is the number of channels, the number of channels is fixed at 2, bit_per_sample is the number of bits of the ADC, and the number of bits is fixed at 16 bits; the delay range is 0 - 4MS, and the adjustment range of buf_len can be obtained by calculation as 0 - 768. The buf_len and the power amplifier sound intensity are adjusted through the left and right balance knobs to make the left and right channel delays reach equilibrium.

[0013] Preferably, in order to achieve the delay purpose, the FIFO buffer area is written to the bottom of the stack, read from the bottom of the stack, and the writing and reading frequencies are the same, both equal to the sampling rate of the audio.

[0014] Preferably, the Bluetooth master control circuit includes an audio input circuit, an audio output circuit, a transfer socket circuit, and a Bluetooth audio decoding circuit, and the audio input circuit, the audio output circuit, and the transfer socket circuit are all electrically connected to the Bluetooth audio decoding circuit.

[0015] Preferably, the vibration massage circuit includes a massage signal output circuit, a vibration pre-amplification circuit, a vibration massage driving circuit, a vibrator temperature sensing circuit, and a cooling fan circuit. The massage signal output circuit is electrically connected to the Bluetooth audio decoding circuit, the vibration pre-amplification circuit, the vibration massage driving circuit, the vibrator temperature sensing circuit, and the cooling fan circuit respectively, and the vibrator temperature sensing circuit is electrically connected to the vibration massage driving circuit.

[0016] Preferably, the audio signal is output from the Bluetooth audio decoding circuit to the input end of the massage signal output circuit. After being processed by the massage signal output circuit, a massage signal is output to the vibration pre-amplification circuit. The vibration pre-amplification circuit amplifies the vibration signal and then outputs the vibration signal to the vibration massage driving circuit. The vibration massage driving circuit performs power amplification on the vibration signal and drives the vibrator to perform vibration massage.

[0017] Preferably, the audio signal is output from the Bluetooth audio decoding circuit to the audio power amplifier circuit. After the audio power amplifier circuit performs DSP sound effect processing and power amplification on the audio signal, it drives the speaker to play music.

[0018] Preferably, the massage signal output circuit is built-in with 5 DAC sine output modules and 3 digital gain adjustment modules. The DAC sine output module includes:

[0019] An ADC converter. When music rhythm massage is required, the audio signal is input to the ADC converter, converted from an analog signal to a digital signal, and then output to the DAC sine wave algorithm converter for further processing;

[0020] A clock resonator generator, which provides a clock frequency for the DAC sine wave algorithm converter;

[0021] A DAC sine algorithm converter. By setting different algorithm parameters, different DAC sine signals can be output;

[0022] A DAC algorithm register, which can store different DAC sine algorithm parameters and can be retrieved when needed;

[0023] A DAC filter, which filters the output DAC sine signal;

[0024] The digital gain adjustment module includes:

[0025] A digital gain adjuster. By setting different parameters, the magnitude of the digital gain can be adjusted;

[0026] A massage signal amplifier that effectively amplifies the output massage signal.

[0027] A serial port controller that processes the externally connected input serial port control signal.

[0028] Adopting the above technical solution, a massage music sofa control system based on channel delay and sound intensity equalization provided by the present invention has the following beneficial effects:

[0029] 1. Utilize sound intensity and channel delay technologies to improve the problem of stereo asymmetry on both sides of a two-seater or three-seater sofa. By adjusting the sound intensity of the left and right channels and compensating for channel delay, high-fidelity music can be reproduced even when the user is sitting in different positions.

[0030] 2. The sound intensity adjustment of the present invention selects to adjust the power of the left and right channels of the power amplifier, rather than adjusting the power of the left and right channels of the main control audio PCM, thus avoiding the problem of abnormal vibration massage caused by the change of the output power of the left and right channels, and enabling the user to have a better music experience and a more comfortable massage effect.

[0031] 3. On the basis of not changing the amplitude of the left and right channels of the main control PCM, better restore the problem of low sound restoration caused by left-right imbalance and phase difference, so that the user has a better music experience and a more comfortable massage effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural block diagram of the present invention;

[0033] Figure 2 It is a massage signal output architecture diagram of DAC sine output and digital gain adjustment in the present invention;

[0034] Figure 3 It is a circuit schematic diagram of the Bluetooth main control circuit in the present invention;

[0035] Figure 4 It is a circuit schematic diagram of the vibration massage circuit in the present invention;

[0036] Figure 5 It is a circuit schematic diagram of the audio power amplifier circuit in the present invention;

[0037] Figure 6 It is a circuit schematic diagram of the hand controller in the present invention;

[0038] In the figure, 1 - Bluetooth main control circuit, 2 - vibration massage circuit, 3 - audio power amplifier circuit, 4 - hand controller. DETAILED DESCRIPTION OF THE INVENTION

[0039] The following further describes the specific embodiments of the present invention in conjunction with the accompanying drawings. It should be noted here that the description of these embodiments is for helping to understand the present invention, but does not constitute a limitation to the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] As Figure 1-6 shown, the massage music sofa control system based on channel delay and sound intensity equalization is composed of four parts: a Bluetooth main control circuit 1, a vibration massage circuit 2, an audio power amplifier circuit 3, and a hand controller 4. The functions of each part are as follows: I. Bluetooth main control circuit: 1) Complete the Bluetooth audio protocol, play Bluetooth songs, and the audio is output after sound effect processing and power amplification through the power amplifier circuit; 2) Communicate with the vibration massage circuit to control the vibration massage to achieve multiple massage waveform outputs; 3) Receive the control signal from the hand controller and complete the corresponding control tasks; display the status of the current control parameters, such as volume level, treble and bass levels, vibration amplitude, and left - right balance.

[0041] I. Bluetooth main control circuit: 1) Complete the Bluetooth audio protocol, play Bluetooth songs, and the audio is output after sound effect processing and power amplification through the power amplifier circuit; 2) Communicate with the vibration massage circuit to control the vibration massage to achieve multiple massage waveform outputs; 3) Receive the control signal from the hand controller and complete the corresponding control tasks; display the status of the current control parameters, such as volume level, treble and bass levels, vibration amplitude, and left - right balance.

[0042] II. Vibration massage circuit: 1) Generate multiple massage vibration waveforms, drive the vibrator after power amplification, and complete the massage of multiple vibration waveforms; 2) Collect the circuit and temperature parameters of the vibrator, and control over - current and over - heat protection.

[0043] III. Audio power amplifier circuit: Complete the sound effect processing and power amplification of the audio coming from Bluetooth.

[0044] IV. Hand controller: 1) Adjust the system volume, treble, bass, left - right balance, and vibration amplitude through the rotary potentiometer, and switch different sound effect modes and vibration modes through buttons; 2) Display the status of each control parameter.

[0045] Specifically, the implementation principle is as follows: When a stereo is installed on both sides of a multi-person sofa, the seat positions that are not in the middle will have inconsistent left and right channel sound intensities and phase deviations due to the inconsistent distances at both ends. To achieve basic balance of the left and right sound intensities, the power of the weak-side channel is increased while the power of the strong-side channel is decreased. This is the solution of current products on the market. However, this method cannot eliminate the phase difference caused by inconsistent distances and will introduce another problem: directly increasing the left and right channels of the sound source will cause the massage oscillator to deviate from the original set value, and the oscillator will not vibrate according to the predetermined value. To eliminate the left and right channel phase difference caused by distance, a delay is added to the Bluetooth master PCM data. The specific implementation method is as follows: A first-in-first-out (FIFO) buffer is created in the RAM area. The size of the buffer determines the delay duration, and the delay duration is adjusted by changing the buffer duration. The calculation formula is buf_len / (SampleRate*channel*bit_per_sample / 8), where buf_len is the size of the created buffer, SampleRate is the sampling rate, which is fixed at 48K in this design, channel is the number of channels, which is fixed at 2 in this design, and bit_per_sample is the number of bits of the ADC, which is fixed at 16 bits in this design. The delay range is 0 - 4MS (exceeding 4MS will cause the left and right channels to sound like different voices in terms of listening perception). According to the formula, the adjustment range of buf_len can be obtained as 0 - 768. The buf_len and the power amplifier sound intensity are adjusted through the left and right balance knobs to make the left and right channel delays balanced. In the present invention, the sound intensity adjustment selects to adjust the left and right channel powers of the power amplifier instead of the left and right channel powers of the master audio PCM. This avoids the problem of abnormal vibration massage caused by the change of the left and right channel output powers, allowing users to have a better music experience and a more comfortable massage effect.

[0046] Specifically, to achieve the time delay purpose, the FIFO stack is designed to write to the bottom of the stack and read from the top of the stack, and the writing and reading frequencies are the same, both equal to the audio sampling rate of 48K. When the rotary potentiometer is rotated, the main control determines which voltage range the potentiometer is currently in, looks up the T_TBL table to obtain the current time delay duration T that should be set, calculates the length value of buf_len using the formula T = buf_len / (SampleRate * channel * bit_per_sample / 8), and sets the length of buf_len. At the same time, to balance the sound intensity of the left and right channels, the T_TBL is set as a two-dimensional array to store the time delay value T and the sound intensity value corresponding to the potentiometer level, and the sound intensity is adjusted while adjusting the delay. It can be understood that the FIFO can be regarded as a pipeline with two ports: data writing and data reading. Among them, the data writing port requires signals: clk, w_req, w_data, and the writing order is 10 - 1; the data reading port requires signals: clk, r_req, and the reading order is: 3, 2, 1. For each bit of data read, the previous bit moves forward one bit.

[0047] Specifically, the principle of the DAC sine output and the massage signal output of the digital gain adjustment is as described: The DAC sine output consists of 5 modules:

[0048] 1. ADC converter. When music rhythm massage is required, the musical rhythm signal is input to the ADC converter, converted from an analog signal to a digital signal, and then output to the DAC sine wave algorithm converter for further processing;

[0049] 2. Clock resonator generator, which provides the clock frequency for the DAC sine wave algorithm converter;

[0050] 3. DAC sine algorithm converter. By setting different algorithm parameters, different DAC sine signals can be output;

[0051] 4. DAC algorithm register, which can save different DAC sine algorithm parameters and be retrieved when needed;

[0052] 5. DAC filter, which filters the output DAC sine signal;

[0053] The massage signal output of the digital gain adjustment consists of 3 modules:

[0054] 1. Digital gain adjuster. By setting different parameters, the magnitude of the digital gain can be adjusted;

[0055] 2. Massage signal amplifier, which effectively amplifies the output massage signal;

[0056] 3. Serial port controller, which processes the externally connected input serial port control signal.

[0057] Specifically, the Bluetooth master control circuit includes an audio input circuit, an audio output circuit, a transfer socket circuit, and a Bluetooth audio decoding circuit. The audio input circuit, the audio output circuit, and the transfer socket circuit are all electrically connected to the Bluetooth audio decoding circuit. It can be understood that the audio input circuit includes interface J13, the audio output circuit includes interface J1, the transfer socket circuit includes socket CON1, and the Bluetooth audio decoding circuit includes decoding chip U1, and the decoding chip U1 uses a BT8961B5QFN52 chip; the audio power amplifier circuit includes power amplifier chip U2 and its peripheral circuit, and the power amplifier chip U2 uses an NTP8835 chip.

[0058] Specifically, the vibration massage circuit includes a massage signal output circuit, a vibration pre-amplification circuit, a vibration massage drive circuit, a vibrator temperature sensing circuit, and a heat dissipation motor circuit. The massage signal output circuit is electrically connected to the Bluetooth audio decoding circuit, the vibration pre-amplification circuit, the vibration massage drive circuit, the vibrator temperature sensing circuit, and the heat dissipation motor circuit respectively, and the vibrator temperature sensing circuit is electrically connected to the vibration massage drive circuit. It can be understood that the massage signal output circuit includes massage signal processing chip U4 and its peripheral circuit, the massage signal processing chip U4 uses a BT8922b2 chip, the vibration pre-amplification circuit includes operational amplifier chip U15 and its peripheral circuit, the operational amplifier chip U15 uses a TP10-2-SR chip, the vibration massage drive circuit includes power amplification chip U10, the power amplification chip U10 uses a TPA3116D chip, the vibrator temperature sensing circuit includes temperature sensor interfaces NTC1, NTC2, NTC3, and NTC4, and temperature sensors are connected to the above temperature sensor interfaces respectively for detecting the temperature of the vibrator; the heat dissipation motor circuit includes fan interface J5 and heat sink interface J19, and the fan interface J5 and the heat sink interface J19 are connected to a heat dissipation fan and a heat sink respectively.

[0059] Specifically, the hand controller includes a panel indicator circuit and a panel control circuit. The panel indicator circuit includes volume adjustment indicators D1 - D16, treble adjustment indicators D17 - D32, bass adjustment indicators D33 - D48, vibration adjustment indicators D49 - D64, left - right balance indicators D65 - D80, and function lights D81 - D93. The panel control circuit includes control knobs VR1 - VR5 and buttons S1 - S4.

[0060] Specifically, the specific working principle of the circuit is as follows:

[0061] 1. U1 is a chip with Bluetooth function, audio decoding and micro-control processing. The music frequency signal outputs an analog music frequency from U1 to the input terminal of U4. U4 is a massage signal processing chip with DAC sine output and digital gain adjustment. The massage signal processed by the U4 algorithm is output to U15. U15 is an operational amplifier chip. After amplifying the vibration signal, it is then transmitted to U10. The integrated circuit U10 is a power amplifier chip, which amplifies the vibration signal in power and drives the vibrator to perform vibration massage.

[0062] 2. U1 is a chip with Bluetooth function, audio decoding and micro-control processing. The serial control signal of the vibration amplitude outputs from U1 to the input terminal of U4. U4 is a massage signal processing chip with DAC sine output and digital gain adjustment. The massage signal processed by the U4 algorithm is output to U15. U15 is an operational amplifier chip. After amplifying the vibration signal, it is then transmitted to U10. U10 is a power amplifier chip, which amplifies the vibration signal in power and drives the vibrator to perform vibration massage.

[0063] 3. Additionally, the music playback signal outputs a digital IIS audio signal from U1 and outputs it to U2. The integrated circuit U2 is a power amplifier + DSP chip, which performs DSP audio effect processing + power amplification on the music signal and drives the speaker to emit a shocking auditory effect of 2.1 channels simulation.

[0064] It can be understood that the design of the present invention is reasonable and the structure is unique, having the following advantages:

[0065] 1. Utilize the sound intensity and channel delay technology to improve the problem of stereo asymmetry on both sides of a two-seater sofa or a three-seater sofa. By adjusting the sound intensity of the left and right channels and compensating the channel delay, high-fidelity music can be reproduced even when the user sits in different positions.

[0066] 2. The sound intensity adjustment of the present invention selects to adjust the power of the left and right channels of the power amplifier, rather than adjusting the power of the left and right channels of the main control audio PCM, thus avoiding the problem of abnormal vibration massage caused by the change of the output power of the left and right channels, and enabling the user to have a better music experience and a more comfortable massage effect.

[0067] 3. On the basis of not changing the amplitude values of the left and right channels of the main control PCM, better restore the problem of low sound reduction caused by left-right imbalance and phase difference, enabling the user to have a better music experience and a more comfortable massage effect.

[0068] The above has described in detail the embodiments of the present invention in conjunction with the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, without departing from the principle and spirit of the present invention, various changes, modifications, substitutions and variations made to these embodiments still fall within the protection scope of the present invention.

Claims

1. A massage music sofa control system based on channel delay and sound intensity balance, characterized in that: include: The Bluetooth main control circuit is used to complete the Bluetooth audio protocol, control the playback of Bluetooth songs, communicate with the vibration massage circuit, control the vibration massage to achieve a variety of massage waveform outputs, receive the control signal of the hand controller and complete the corresponding control tasks; The vibration massage circuit is used to generate a variety of massage vibration waveforms, drive the vibrator after power amplification, and complete massage with a variety of vibration waveforms; Audio power amplifier circuit, the audio signal is processed by the audio power amplifier circuit for sound effect and power amplification before being output; The hand controller is used to adjust the system volume, treble, bass, left and right balance, and vibration amplitude through the knob potentiometer, and switch different sound effect modes and vibration modes through the button.

2. The massage music sofa control system based on channel delay and sound intensity balance according to claim 1 is characterized in that: The Bluetooth main control circuit decodes PCM data and opens a first-in-first-out FIFO buffer in the RAM area. The size of the buffer determines the delay duration. The purpose of adjusting the delay duration is achieved by changing the buffer duration. The calculation formula is T=buf_len / (SampleRate*channel*bit_per_sample / 8), wherein buf_len is the size of the opened buffer, SampleRate is the sampling rate, the sampling rate is fixed to 48K, channel is the number of channels, the number of channels is fixed to 2, bit_per_sample is the number of bits of ADC, and the number of bits is fixed to 16 bits; the delay range is 0-4MS, and the adjustment range of buf_len can be obtained from the formula to be 0-768, and buf_len and the power amplifier sound intensity are adjusted by the left and right balance knobs to balance the delay of the left and right channels.

3. The massage music sofa control system based on channel delay and sound intensity balance according to claim 2 is characterized in that: In order to achieve the delay purpose, the FIFO buffer is written to the bottom of the stack and read in a fixed mode, and the frequency of writing and reading is the same, which is equal to the sampling rate of the audio.

4. The massage music sofa control system based on channel delay and sound intensity balance according to claim 1 is characterized in that: The Bluetooth main control circuit includes an audio input circuit, an audio output circuit, a switching socket circuit and a Bluetooth audio decoding circuit. The audio input circuit, the audio output circuit and the switching socket circuit are all electrically connected to the Bluetooth audio decoding circuit.

5. The massage music sofa control system based on channel delay and sound intensity balance according to claim 4 is characterized in that: The vibration massage circuit includes a massage signal output circuit, a vibration preamplifier circuit, a vibration massage drive circuit, a vibrator temperature sensing circuit and a heat dissipation motor circuit. The massage signal output circuit is electrically connected to the Bluetooth audio decoding circuit, the vibration preamplifier circuit, the vibration massage drive circuit, the vibrator temperature sensing circuit and the heat dissipation motor circuit respectively, and the vibrator temperature sensing circuit is electrically connected to the vibration massage drive circuit.

6. The massage music sofa control system based on channel delay and sound intensity balance according to claim 5 is characterized in that: The audio signal is output from the Bluetooth audio decoding circuit to the input end of the massage signal output circuit, and the massage signal is output to the vibration preamplifier circuit after signal processing by the massage signal output circuit. The vibration preamplifier circuit amplifies the vibration signal and outputs the vibration signal to the vibration massage drive circuit. The vibration massage drive circuit amplifies the power of the vibration signal and drives the vibrator to perform vibration massage.

7. The massage music sofa control system based on channel delay and sound intensity balance according to claim 5 is characterized in that: The audio signal is output from the Bluetooth audio decoding circuit to the audio power amplifier circuit, and the audio power amplifier circuit performs DSP sound effect processing and power amplification on the audio signal to drive the speaker to play music.

8. The massage music sofa control system based on channel delay and sound intensity balance according to claim 5 is characterized in that: The massage signal output circuit has five built-in DAC sinusoidal output modules and three digital gain adjustment modules. The DAC sinusoidal output module includes: ADC converter, when music rhythm massage is needed, the audio signal is input to the ADC converter, converted from analog signal to digital signal, and then output to the DAC sine wave algorithm converter for the next step of processing; A clock resonance generator provides a clock frequency for the DAC sine wave algorithm converter; DAC sine algorithm converter, by setting different algorithm parameters, can output different DAC sine signals; DAC algorithm register, which can save different DAC sine algorithm parameters and call them out when needed; DAC filter, filtering the output DAC sinusoidal signal; The digital gain adjustment module comprises: Digital gain adjuster, by setting different parameters, the magnitude of digital gain can be adjusted; Massage signal amplifier, which effectively amplifies the output massage signal; The serial port controller processes the external input serial port control signal.

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