Auxiliary hearing device

Abstract

The utility model provides an auxiliary hearing device. The auxiliary hearing device comprises an automatic switching circuit, an automatic gain pre-amplification circuit, a sound path amplification circuit, a single-chip microcomputer, a volume adjustment and power amplification circuit and N microphones, the automatic conversion circuit connects the N microphones with the automatic gain pre-amplification circuit in different time periods, and transmits audio signals of the microphones to the automatic gain pre-amplification circuit; the automatic gain pre-amplification circuit processes the audio signal, so that the intensity of the audio signal is within a preset intensity range, and the audio signal is transmitted to the sound path amplification circuit; the single chip microcomputer sends an amplification instruction to the sound path amplification circuit; the sound path amplification circuit divides the audio signal into a plurality of sound paths according to frequency bands; the audio signals of each sound path are amplified according to the amplification instruction and then transmitted to the volume adjustment and power amplification circuit; and the volume adjustment and power amplification circuit adjusts the volume of the audio signal according to the adjustment instruction and outputs the sound. The application can effectively improve the sound quality of hearing and audio signals.

Description

Technical Field

[0001] This application relates to the field of hearing aid technology, and more particularly to an assistive hearing device. Background Technology

[0002] Hearing aids are classified as Class II medical devices, subject to extremely stringent requirements regarding human safety, hygiene, environmentally friendly materials, product quality, and medical clinical trials. Therefore, the production and sales licenses for hearing aids are subject to extremely rigorous review and regulations. Similarly, strict medical and product technical specifications govern the medical diagnosis, testing, and fitting / adjustment of hearing aids, creating high barriers to entry for hearing aids into the market.

[0003] Hearing aids are devices that bridge the gap between medicine and physics, synthesized through highly complex micromechanical, microelectronic, and specialized acoustic technologies, thus creating a high technological barrier from research and development to production. Furthermore, the cost of hearing aids involves medical diagnostic and testing equipment, instruments for fitting and adjusting the device, and the fees of hearing aid fitters. This results in high costs and exorbitant prices, leading to a widespread phenomenon where hearing-impaired patients cannot afford them, research and manufacturing companies experience low profits, and hearing aid adoption rates remain low.

[0004] To address the aforementioned issues, the over-the-counter (OTC) drug model led to the emergence of OTC hearing aids. OTC hearing aids, also known as assistive hearing aids, are personal sound amplifiers. These assistive hearing aids provide hearing-impaired patients with affordable and convenient new hearing aids, while simplifying the approval (inspection) procedures for the production, sale, and use of traditional hearing aids. Furthermore, they reflect the flexibility and practicality of government regulations governing medical devices. However, in practical applications, while assistive hearing aids have brought benefits to patients with mild to moderate hearing impairment, there have also been cases of harm to these patients. For example, some existing assistive hearing aids, due to an overemphasis on amplification, can cause self-oscillation in the circuitry, producing a whistling sound that stimulates the auditory nerve of hearing-impaired patients, thus causing damage. In addition, when using hearing aids or assistive hearing devices, the inability of hearing-impaired patients to hear sounds is not only related to their hearing loss, but also to the frequency range of the sounds amplified by the hearing aids or assistive hearing devices; the inability of hearing-impaired patients to hear sound content clearly is not only related to their decreased speech resolution, but also to the way hearing aids or assistive hearing devices process multiple overtones and harmonics above the fundamental frequency of sound. Utility Model Content

[0005] In view of this, the present invention provides an auxiliary hearing device, which can effectively improve the sound quality of audio signals and enhance the user experience.

[0006] The technical solution of this application is implemented as follows:

[0007] This application provides an assistive hearing device, which includes: an automatic conversion circuit, an automatic gain preamplifier circuit, an acoustic path amplifier circuit, a microcontroller, a volume adjustment and power amplifier circuit, and N microphones; wherein N is an integer greater than or equal to N.

[0008] The automatic switching circuit is used to connect N microphones to the automatic gain preamplifier circuit in time periods, and transmit the audio signals received by each microphone during its connected time period to the automatic gain preamplifier circuit.

[0009] The automatic gain preamplifier circuit is used to process the received audio signal so that the intensity of the processed audio signal is within a preset intensity range, and to transmit the processed audio signal to the acoustic path amplifier circuit.

[0010] The microcontroller is used to send amplification instructions to the acoustic path amplification circuit, and the amplification instructions include amplification factor information corresponding to multiple acoustic paths;

[0011] The sound path amplification circuit is used to divide the received audio signal into multiple sound paths according to the frequency band; according to the received amplification command, the audio signal of each sound path is amplified respectively, and the amplified audio signal of each sound path is transmitted to the volume adjustment and power amplification circuit.

[0012] The volume adjustment and power amplification circuit is used to adjust the volume of the received audio signal according to the received adjustment command, and output the adjusted audio signal.

[0013] As can be seen above, in the hearing aid device of this utility model, since the automatic switching circuit connects to N microphones in time periods and transmits the audio signals received by each microphone when connected to the automatic switching circuit to the automatic gain preamplifier circuit, N microphones can be used in a loop in different time periods to switch between different sound paths, thereby effectively suppressing feedback. In addition, since the audio signal can be processed by the automatic gain preamplifier circuit to make the intensity of the processed audio signal within a preset intensity range (for example, about 25 dB), and then the sound path amplification circuit divides the audio signal into multiple sound paths according to frequency bands, and amplifies the audio signal of each sound path according to different amplification factors according to the amplification instructions sent by the microcontroller, the audio signal within the user's hearing frequency range can be effectively amplified in a targeted manner, while other noise signals can be effectively suppressed. This makes it easier for the user to hear the sound content in the audio signal, and can also effectively improve hearing and the sound quality of the audio signal, thereby improving the user experience. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of an assistive hearing device in a specific embodiment of this application.

[0015] Figure 2 This is a schematic diagram of the automatic switching circuit in a specific embodiment of this application. Figure 1 .

[0016] Figure 3 This is a schematic diagram of the automatic switching circuit in a specific embodiment of this application. Figure 2 .

[0017] Figure 4 This is a schematic diagram of the automatic gain preamplifier circuit in a specific embodiment of this application.

[0018] Figure 5 This is a schematic diagram of the structure of the fourth chip IC4 in a specific embodiment of this application.

[0019] Figure 6 This is a schematic diagram of the structure of the fifth chip IC5 in a specific embodiment of this application.

[0020] Figure 7 This is a schematic diagram of the acoustic path amplifier circuit in a specific embodiment of this application.

[0021] Figure 8 This is a schematic diagram of the structure of a multi-order active bandpass filter in a specific embodiment of this application. Detailed Implementation

[0022] To make the technical solution and advantages of this utility model clearer, the following description, in conjunction with the accompanying drawings and specific embodiments, will provide a more detailed explanation of this utility model.

[0023] Figure 1 This is a schematic diagram of the structure of the hearing aid device in the embodiment of this utility model, as shown below. Figure 1 As shown, the hearing aid in this embodiment includes: an automatic conversion circuit 101, an automatic gain preamplifier circuit 102, a sound path amplifier circuit 103, a microcontroller 104, a volume adjustment and power amplification circuit 105, and N microphones 106; wherein, N is an integer greater than or equal to 2.

[0024] The automatic switching circuit 101 is used to connect N microphones 106 to the automatic gain preamplifier circuit 102 in time periods, and transmit the audio signals received by each microphone 106 during the time period it is connected to the automatic gain preamplifier circuit 102.

[0025] The automatic gain preamplifier circuit 102 is used to process the received audio signal so that the intensity of the processed audio signal is within a preset intensity range, and to transmit the processed audio signal to the acoustic path amplifier circuit 103.

[0026] The microcontroller 104 is used to send amplification instructions to the acoustic amplifier circuit 103, and the amplification instructions include amplification factor information corresponding to multiple acoustic paths.

[0027] The sound path amplification circuit 103 is used to divide the received audio signal into multiple sound paths according to the frequency band; according to the received amplification command, the audio signal of each sound path is amplified respectively, and the amplified audio signal of each sound path is transmitted to the volume adjustment and power amplification circuit 105.

[0028] The volume adjustment and power amplification circuit 105 is used to adjust the volume of the received audio signal according to the received adjustment command, and output the adjusted audio signal.

[0029] In the aforementioned hearing aid device of this application, since the automatic switching circuit connects to N microphones in time intervals and transmits the audio signals received by each microphone when connected to the automatic switching circuit to the automatic gain preamplifier circuit, N microphones can be used cyclically in different time intervals to switch between different sound paths. This minimizes the repeated positive feedback of sound waves entering from the microphone, passing through the automatic gain preamplifier circuit, sound path amplification circuit, volume adjustment and power amplification circuit, and then reflecting back to the microphone. This eliminates the necessary conditions for "circuit feedback" in the electronic amplification circuit, namely, the lack of phase condition and oscillation amplitude—the two basic elements for generating feedback sound. Consequently, the sound waves no longer have the conditions for self-excitation in the electronic amplification circuit, effectively suppressing howling. Therefore, the hearing aid device of this application is actually a howling-free hearing aid (which can be called a superior hearing aid).

[0030] Furthermore, in the aforementioned hearing aid device of this application, since the audio signal can be processed by an automatic gain preamplifier circuit to make the intensity of the processed audio signal within a preset intensity range (e.g., about 25 dB), and then the audio signal is divided into multiple sound paths according to frequency bands by a sound path amplification circuit, and the audio signal of each sound path is amplified by different amplification factors according to the amplification instructions sent by the microcontroller, the audio signal within the user's hearing frequency range can be effectively amplified in a targeted manner, while other noise signals are effectively suppressed. This makes it easier for the user to hear the sound content in the audio signal clearly, and can also effectively improve the sound quality of the audio signal to enhance the user's experience.

[0031] Furthermore, the aforementioned hearing aid device can be implemented in various specific ways in this application. The following will use several specific methods as examples to provide a detailed description of the technical solution of this application.

[0032] In the technical solution of this application, the number of microphones, i.e., the value of N, can be preset according to the needs of the actual application scenario.

[0033] For example, as an example, in a preferred embodiment of this application, the value of N can be 2, 3, 4 or 5, or other suitable values, which will not be listed here.

[0034] When using the aforementioned N microphones, a cycle can be divided into multiple time periods of equal (or unequal) duration. An automatic switching circuit connects the N microphones to the circuit in turn during each time period, ensuring that only one microphone is connected to the circuit during each period. This allows the audio signal received by the connected microphone during that period to be transmitted to the automatic gain preamplifier circuit. In other words, the N microphones can be used cyclically across different time periods within a cycle, enabling switching between different audio paths to effectively suppress feedback.

[0035] For example, when N is 2, that is, when 2 microphones are set, a cycle (e.g., 1 second) can be divided into 4 time periods of equal length (e.g., each time period can be 250 milliseconds). In the first time period, the first microphone is connected to the automatic switching circuit; in the second time period, the second microphone is connected to the automatic switching circuit; in the third time period, the first microphone is connected to the automatic switching circuit; and in the fourth time period, the second microphone is connected to the automatic switching circuit.

[0036] For another example, when N is 3, meaning 3 microphones are set, a cycle (e.g., 1 second) can be divided into 4 equal-length time periods (e.g., each time period can be 250 milliseconds). In the first time period, the first microphone MIC1 is connected to the automatic switching circuit; in the second time period, the second microphone MIC2 is connected; in the third time period, the third microphone MIC3 is connected; and in the fourth time period, the second microphone MIC2 is connected, and so on. Figure 3 As shown.

[0037] For another example, when N is 4, that is, when 4 microphones are set, a cycle (e.g., 1 second) can be divided into 4 time periods of equal length (e.g., each time period can be 250 milliseconds). In the first time period, the first microphone is connected to the automatic switching circuit; in the second time period, the second microphone is connected to the automatic switching circuit; in the third time period, the third microphone is connected to the automatic switching circuit; and in the fourth time period, the fourth microphone is connected to the automatic switching circuit.

[0038] When N takes other values, the same principle applies, and they will not be listed one by one here.

[0039] Additionally, as an example, in a preferred embodiment of this application, when N is 2, the N microphones may include: a first upper-entry silicon microphone and a first lower-entry silicon microphone.

[0040] For example, in a preferred embodiment of this application, when N is 3, the N microphones may include: a first upward-facing silicon microphone MIC1, a first bottom-facing silicon microphone MIC2, and a second upward-facing silicon microphone MIC3, such as... Figure 3 As shown.

[0041] For example, as an example, in a preferred embodiment of this application, when the value of N is 4, the N microphones may include: a first upward-facing silicon microphone MIC1, a first bottom-facing silicon microphone MIC2, a second upward-facing silicon microphone MIC3, and a second bottom-facing silicon microphone MIC4.

[0042] Additionally, as an example, such as Figure 2 As shown, in a preferred embodiment of this application, the automatic switching circuit 101 may include: a first chip IC1 and a second chip IC2;

[0043] The first chip IC1 is used to send switch control signals corresponding to N microphones to the second chip IC2 according to the received clock pulse signal;

[0044] The N microphones are respectively connected to the second chip IC2;

[0045] The second chip IC2 is used to turn on or off the corresponding microphone according to the received switch control signal, connect N microphones to the automatic gain preamplifier circuit 102 in time periods, and transmit the audio signal received by each microphone during its connected time period to the automatic gain preamplifier circuit 102.

[0046] Additionally, as an example, in one specific embodiment of this application, the N microphones can be connected to the automatic gain preamplifier circuit 102 via wired or wireless means.

[0047] Additionally, as an example, in a preferred embodiment of this application, the first chip IC1 may be a decimal counter circuit; the second chip IC2 may be a quad-gang analog switch.

[0048] Additionally, as an example, in a preferred embodiment of this application, the first chip IC1 can also be used to receive a first reset pulse signal and a second reset pulse signal; perform a global reset according to the first reset pulse signal; and perform a cyclic reset according to the second reset pulse signal.

[0049] Therefore, the first chip IC1 can perform a global reset based on the first reset pulse signal, resetting the entire hearing aid to a preset initial state. It can also perform a cyclic reset based on the second reset pulse signal, thereby starting the next cyclic cycle and switching each microphone in the next round.

[0050] For example, as an example, such as Figure 3 As shown, when N is 3, that is, when 3 microphones are set, in a preferred embodiment of this application:

[0051] The first chip IC1 has a clock pin 14, a reset pin 15, and four analog switch pins (e.g., Figure 3 Pins 3, 2, 4, and 7 on IC1 shown;

[0052] The second chip IC2 has four control pins (for example, Figure 3 The IC2 shown has pins 13, 5, 6, and 12, and four microphone pins (e.g., ...). Figure 3 The IC2 shown has pins 1, 3, 8, and 10 and four output pins (e.g., ...). Figure 3 Pins 11, 9, 4, and 2 on IC2 shown in the diagram; wherein the four analog switch pins, four control pins, four microphone pins, and four output pins correspond one-to-one;

[0053] Two of the three microphones are connected at one end to a corresponding microphone pin on the second chip IC2, and the other microphone is connected at one end to two microphone pins on the second chip IC2 (for example, ...). Figure 3As shown, one end of the first upper-entry silicon microphone MIC1 and the second upper-entry silicon microphone MIC3 are respectively connected to pins 1 and 8 on IC2, while one end of the first lower-entry silicon microphone MIC2 is connected to pins 3 and 10 on IC2.

[0054] The clock pin 14 of the first chip IC1 is used to receive clock pulse signals;

[0055] The reset pin 15 of the first chip IC1 is used to receive the first reset pulse signal and the second reset pulse signal;

[0056] The four analog switch pins on the first chip IC1 are connected one-to-one with the four control pins on the second chip IC2 (for example, the four analog switch pins 3, 2, 4, and 7 on IC1 are connected one-to-one with the four control pins 13, 5, 6, and 12 on IC2), and are used to send switch control signals to the corresponding control pins of the second chip IC2 according to the clock pulse signal.

[0057] The four control pins on the second chip IC2 are used to send the received switch control signals to the corresponding microphone pins.

[0058] The four microphone pins on the second chip IC2 are connected one-to-one with the four output pins, which are used to turn the connected microphone on or off according to the received switch control signal, and transmit the audio signal received by the connected microphone during the time period when it is turned on to the corresponding output pin.

[0059] The four output pins on the second chip IC2 are all connected to the microphone (MIC) signal bus, and the received audio signal is transmitted to the automatic gain preamplifier circuit through the microphone signal bus and the third coupling capacitor C3.

[0060] In the technical solution of this application, when the first chip IC1 receives a clock pulse signal, it can output a switch control signal (e.g., high or low level signal) to the second chip IC2 at a preset frequency. The second chip IC2 will turn on or off N microphones according to the received switch control signal, so that the N microphones are connected to the automatic gain preamplifier circuit in turn and at different time periods. Only one microphone is connected to the automatic gain preamplifier circuit at the same time period, and the audio signal received by the connected microphone during that time period is transmitted to the automatic gain preamplifier circuit.

[0061] In the specific embodiment described above, since three microphones are provided, and four analog switch pins, four control pins, four microphone pins, and four output pins are respectively provided, one cycle can be divided into four time periods of equal duration. For example, when the duration of one cycle is 1 second, the duration of each time period can be 250 milliseconds. In the first time period, MIC1 is connected to the automatic conversion circuit; in the second time period, MIC2 is connected to the automatic conversion circuit; in the third time period, MIC3 is connected to the automatic conversion circuit; and in the fourth time period, MIC2 is connected to the automatic conversion circuit (MIC2 is used twice in one cycle). Therefore, the automatic conversion circuit can connect the three microphones to the automatic conversion circuit in turn during the four time periods, ensuring that only one microphone is connected to the automatic conversion circuit in each time period, so that the audio signal received by the microphone connected in that time period is transmitted to the automatic gain preamplifier circuit. By using the above method, N microphones can be used cyclically in various time periods within a cycle (e.g., 1 second). Every so often (e.g., 250 milliseconds), the connection between the currently active microphone and the automatic gain preamplifier circuit is interrupted, effectively changing the sound path four times within one cycle. Due to the speed of sound, it is difficult to generate repeated positive feedback within a single time period (e.g., 250 milliseconds) where sound waves travel from the microphone input to the electronic amplifier circuit and then reflect back to the microphone from the speaker output (in practical applications, feedback typically requires at least 2 seconds of repeated positive feedback). Therefore, by cyclically switching the sound path, the necessary conditions for generating "circuit feedback" in the electronic amplifier circuit are eliminated—namely, the phase condition and oscillation amplitude, the two fundamental elements for generating feedback sound. This prevents the sound waves from self-excited within the electronic amplifier circuit, effectively suppressing feedback.

[0062] In addition, in other specific implementations of this application (e.g., using other numbers of microphones and other numbers of time periods, etc.), similar principles or methods can be used to effectively suppress howling, which will not be listed here one by one.

[0063] Additionally, as an example, in a preferred embodiment of this application, the clock pin 14 is further provided with a first delay circuit including a first resistor R1 and a first capacitor C1, which is used to make the rising and falling edges of the received clock pulse signal have a preset tilt angle, so as to prevent noise interference from the first chip IC1 and causing malfunctions, affecting the normal operation of multiple microphones in turn.

[0064] The reset pin 15 is further provided with a second delay circuit including a second resistor R2 and a second capacitor C2, which is used to make the rising and falling edges of the received reset pulse signal have a preset tilt angle to prevent noise interference from the first chip IC1 and causing malfunctions, affecting the normal operation of multiple microphones in turn.

[0065] Additionally, as an example, in a preferred embodiment of this application, the first chip IC1 is further provided with an output pin Q4, a power supply pin VDD, and a ground pin VSS;

[0066] The output pin (i.e.) Figure 3 Pin 10 of IC1 shown is connected to the reset pin 15 via the second diode D2, for outputting a second reset pulse signal at the end of a cycle;

[0067] The power supply pin VDD (i.e. Figure 3 Pin 16 of IC1 shown is used to connect to the power supply;

[0068] The ground pin VSS (i.e. Figure 3 Pin 13 of IC1 shown is used to connect to ground.

[0069] With the second reset pulse signal mentioned above, the first chip IC1 can start the next cycle and perform the next round of switching between each microphone.

[0070] Additionally, as an example, in a preferred embodiment of this application, the first chip IC1 is further provided with a fifteenth capacitor C15. One end of the fifteenth capacitor C15 is connected to the power supply pin VDD of the first chip IC1, and the other end is grounded. It is used to filter AC signals in the circuit, prevent them from entering the power supply circuit, protect the power supply, and bypass AC signals.

[0071] Additionally, as an example, in a preferred embodiment of this application, the second chip IC2 is further provided with a power supply pin VDD and a ground pin GND;

[0072] The power supply pin VDD (i.e. Figure 3 Pin 14 of IC2 shown is used to connect to the power supply;

[0073] The ground pin GND (i.e. Figure 3 Pin 7 of IC2 shown is used to connect to ground.

[0074] Additionally, as an example, in a preferred embodiment of this application, the automatic switching circuit 101 may further include: a voltage regulator IC7, a first bypass capacitor (e.g., Figure 3The capacitor C19 shown) and multiple second bypass capacitors (e.g., Figure 3 The capacitors C14 and C9 shown are shown in the diagram.

[0075] The first terminal of the voltage regulator IC7 is connected to the power supply pin VDD of the first chip IC1 and the power supply pin VDD of the second chip IC2, and the second terminal is connected to the power supply (not shown in the figure), which is used to convert the voltage of the power supply into the operating voltage required by the first chip IC1 and the second chip IC2.

[0076] One end of the first bypass capacitor is connected to the power supply (not shown in the figure), and the other end is grounded; it is used to filter AC signals in the circuit.

[0077] One end of the second bypass capacitor is connected to the first end of the voltage regulator IC7, and the other end is grounded; it is used to filter AC signals in the circuit.

[0078] The voltage regulator IC7 described above can convert the power supply voltage (e.g., 11.1 volts) into the operating voltage required by the first chip IC1 and the second chip IC2 (e.g., 5 volts); while the first bypass capacitor and the second bypass capacitor can filter the AC signal in the circuit, prevent it from entering the power supply circuit, protect the power supply, and bypass the AC signal.

[0079] Additionally, as an example, such as Figure 4 As shown, in a preferred embodiment of this application, the automatic gain preamplifier circuit 102 may include: a third chip IC3, a fourth chip IC4, a fifth chip IC5, and a voltage divider circuit;

[0080] The first input terminal of the third chip IC3 is connected to the output terminal of the automatic conversion circuit 101; the output terminal of the third chip IC3 is connected to one input terminal of the fourth chip IC4.

[0081] The first output terminal of the fourth chip IC4 is connected to one input terminal of the fifth chip IC5; the second output terminal of the fourth chip IC4 is connected to the acoustic amplifier circuit 103.

[0082] The output terminal of the fifth chip IC5 is connected to the second input terminal of the third chip IC3;

[0083] The third chip IC3 is used to transmit the audio signal received from the first input terminal to the fourth chip IC4, calculate the product of the signals received from the first input terminal and the second input terminal, and output the product as a gain value to the fourth chip IC4.

[0084] The fourth chip IC4 is used to amplify the received audio signal in the first stage according to the received gain value; when the intensity of the amplified signal is within a preset intensity range, the amplified signal is output to the acoustic path amplifier circuit 103; when the intensity of the amplified signal is not within the preset intensity range, the amplified signal is rectified and output to the fifth chip IC5.

[0085] The voltage divider circuit includes: a first adjustable voltage divider resistor R. k-1 Second adjustable voltage divider resistor R k-2 The first adjustable voltage divider resistor R k-1 The first terminal is connected to the power supply, and the second terminal is connected to the second adjustable voltage divider resistor R. k-2 The first terminal is connected to the fifth chip IC5; the second adjustable voltage divider resistor R k-2 The second terminal is grounded;

[0086] The fifth chip IC5 is used to perform low-pass filtering on the received signal, determine the corresponding amplification factor according to the voltage output of the voltage divider circuit, and perform a second-stage amplification on the low-pass filtered signal according to the determined amplification factor before outputting it to the third chip IC3.

[0087] In the specific embodiments described above in this application, the third chip IC3 in the automatic gain preamplifier circuit 102 can receive the audio signal output by the automatic conversion circuit 101 through the first input terminal (which may be called the audio signal input terminal), and receive the amplified signal output by the fifth chip IC5 through the second input terminal (which may be called the reference signal input terminal). Therefore, it can calculate the product of the signals received from the first input terminal and the second input terminal, and output the product as a gain value to the fourth chip IC4. The fourth chip IC4 can then amplify the received audio signal according to the received gain value. If the intensity of the amplified signal is within a preset intensity range, the amplified signal can be directly output to the acoustic path amplifier circuit 103. If the amplified signal is within a preset intensity range, the amplified signal can be directly output to the acoustic path amplifier circuit 103. When the strength of the amplified signal is not within the preset strength range, the amplified signal can be rectified and output to the fifth chip IC5. The fifth chip IC5 first performs low-pass filtering on the received signal, and then determines the corresponding amplification factor according to the voltage output by the voltage divider circuit (which can be called the automatic gain control voltage UREF). Subsequently, the low-pass filtered signal is amplified in the second stage according to the amplification factor, and then output to the second input terminal of the third chip IC3, thus starting the next closed loop until the strength of the audio signal is within the preset strength range. Then, the fourth chip IC4 outputs the audio signal to the sound path amplifier circuit 103, so that the strength of the audio signal received by the sound path amplifier circuit 103 is within the preset strength range.

[0088] In the technical solution of this application, the above-mentioned preset intensity range can be set in advance according to the needs of the actual application scenario.

[0089] For example, as an example, in a preferred embodiment of this application, the preset intensity range can be 25 dB, with a fluctuation of no more than 2.5 dB, that is, the preset audio signal intensity range can be [22.5, 27.5] dB.

[0090] Of course, the above-mentioned preset range of audio signal intensity can also be other suitable values, such as [20, 30] decibels, etc., which will not be listed here.

[0091] Therefore, through the automatic gain preamplifier circuit 102 described above, the intensity of the output audio signal can be limited to a preset intensity range, for example, about 25 dB. This can enhance the audio signal with a lower intensity in the original audio signal and weaken the audio signal with a higher intensity in the original audio signal, so that the intensity of the audio signal received by the acoustic path amplifier circuit 103 is within the preset intensity range.

[0092] Additionally, as an example, in a preferred embodiment of this application, the third chip IC3 may be an analog multiplier.

[0093] Additionally, as an example, such as Figure 5 As shown, in a preferred embodiment of this application, the fourth chip IC4 may include: a first-stage amplifier circuit and a precision rectifier circuit;

[0094] One input terminal of the first-stage amplifier circuit is connected to the output terminal of the third chip IC3; the output terminal of the first-stage amplifier circuit is connected to one input terminal of the precision rectifier circuit and the input terminal of the acoustic path amplifier circuit 103, respectively.

[0095] The output terminal of the precision rectifier circuit is connected to the input terminal of the fifth chip IC5;

[0096] The first-stage amplifier circuit is used to amplify the received audio signal according to the received gain value; when the intensity of the amplified signal is within a preset intensity range, the amplified signal is output to the acoustic path amplifier circuit 103; when the intensity of the amplified signal is not within the preset intensity range, the amplified signal is output to the precision rectifier circuit.

[0097] The precision rectifier circuit is used to rectify the received signal and output the rectified signal to the fifth chip IC5.

[0098] In the technical solution of this application, the signal output by the third chip IC3 can be amplified by the first stage amplifier circuit in the fourth chip IC4 (for example, the first stage gain can be preset to 10 to 25 dB). If the intensity of the signal amplified by the first stage amplifier circuit is within the preset intensity range, the amplified signal can be directly output to the acoustic path amplifier circuit 103. If the intensity of the amplified signal is not within the preset intensity range, the amplified signal can be output to the precision rectifier circuit. After rectification by the precision rectifier circuit, the full-wave pulsating signal of the audio can be obtained and output to the fifth chip IC5.

[0099] Additionally, as an example, such as Figure 6 As shown, in a preferred embodiment of this application, the fifth chip IC5 may include: a first-order active filter circuit and a second-stage amplifier circuit;

[0100] One input terminal of the first-order active filter circuit is connected to the first output terminal of the fourth chip IC4, and the output terminal of the first-order active filter circuit is connected to the first input terminal of the second-stage amplifier circuit.

[0101] The second input terminal of the second-stage amplifier circuit is connected to the output terminal of the voltage divider circuit; the output terminal of the second-stage amplifier circuit is connected to the second input terminal of the third chip IC3.

[0102] The first-order active filter circuit is used to perform low-pass filtering on the received signal and output the low-pass filtered signal to the second-stage amplifier circuit.

[0103] The second-stage amplifier circuit is used to determine the corresponding amplification factor based on the voltage output of the voltage divider circuit, and then amplify the low-pass filtered signal according to the determined amplification factor before outputting it to the third chip IC3.

[0104] In the technical solution of this application, the full-wave pulsating audio signal output by the fourth chip IC4 can be filtered by the first-order active filter circuit to make the pulsation amplitude of the signal tend to a stable average DC level; then it is amplified by the second-stage amplifier circuit (for example, the second-stage gain can be preset to about 10 dB) to obtain the amplified signal, which is then output to the third chip IC3 to meet the operating conditions of the third chip IC3. The first-stage amplifier circuit in the fourth chip IC4 and the second-stage amplifier circuit in the fifth chip IC5 are adjusted according to the gain of the audio signal required in the actual application. Therefore, the fourth chip IC4 and the fifth chip IC5 can form a closed-loop automatic gain amplifier circuit.

[0105] Furthermore, the automatic gain control voltage UREF output from the voltage divider circuit can be input into the second-stage amplifier circuit through the second input terminal of the second-stage amplifier circuit, and the automatic gain control voltage UREF is determined by the first adjustable voltage divider resistor R. k-1 Second adjustable voltage divider resistor R k-2 The signal is obtained by voltage division from the main power supply. Therefore, the second-stage amplifier circuit can determine the corresponding amplification factor based on the automatic gain control voltage UREF output by the voltage divider circuit. Then, based on this amplification factor, the low-pass filtered signal is amplified in the second stage and output to the second input terminal of the third chip IC3 as a reference signal for the third chip IC3, thus starting the next closed-loop cycle. When the intensity of the audio signal is within the preset intensity range, the fourth chip IC4 outputs the audio signal to the sound path amplifier circuit 103, so that the intensity of the audio signal received by the sound path amplifier circuit 103 is within the preset intensity range.

[0106] Additionally, as an example, such as Figure 7 As shown, in a preferred embodiment of this application, the acoustic path amplifier circuit 103 may include: M multi-order active bandpass filters, an acoustic path configurator, a multiplier stage configuration circuit, and each acoustic path multiplier stage amplifier circuit;

[0107] The M multi-stage active bandpass filters are used to perform low-pass filtering and high-pass filtering on the received audio signal respectively, divide the received audio signal into M audio signals according to frequency band, and output the filtered audio signal to the audio path configurator.

[0108] The sound path configurator is used to output the received audio signals of each sound path to the multiplier configuration circuit, record the frequency band information of the audio signals of each sound path, and output the recorded frequency band information to the microcontroller 104.

[0109] The multiplier stage configuration circuit is used to determine the amplification factor corresponding to the audio signal of each received sound path according to the received amplification instruction, and output the corresponding amplification factor to the multiplier stage amplification circuit respectively.

[0110] The multiplier stage amplifier circuit is used to amplify the received audio signals of each audio path according to the amplification factor corresponding to each audio path, and transmit the amplified audio signals of each audio path to the volume adjustment and power amplification circuit 105.

[0111] In the technical solution of this application, the number of the above-mentioned acoustic path and multi-order active bandpass filter, i.e., the value of M, can be preset according to the needs of the actual application scenario.

[0112] For example, as an example, in a preferred embodiment of this application, the value of M can be 4, 8, 16, 24, 30, 32, 48, 56, 60, 64, 90, 100, 120, 128, 200, or 1000, or other suitable values, which will not be listed here. Generally, the larger the value of M, the more sound paths there are, and the better the sound effect.

[0113] In the specific embodiments described above in this application, if it is necessary to divide the received audio signal into M sound paths according to frequency bands, M multi-order active bandpass filters can be set so that each sound path corresponds to a multi-order active bandpass filter. Each multi-order active bandpass filter can perform low-pass filtering and high-pass filtering on the audio signal of its corresponding sound path to suppress the corresponding high-frequency and low-frequency signals, allowing only audio signals within a preset frequency range to pass through, thereby removing the corresponding noise and interference to provide a clearer audio signal.

[0114] Furthermore, each multi-stage active bandpass filter is connected to a multiplier stage configuration circuit via a path configurator. This path configurator records the frequency band information of the audio signals from each path and outputs all recorded frequency band information to the microcontroller 104. The microcontroller 104, based on the frequency band information of the audio signals from each path, outputs corresponding amplification commands to the multiplier stage configuration circuit, carrying the amplification factor information corresponding to each path to be amplified. Therefore, the multiplier stage configuration circuit can determine the amplification factor corresponding to the audio signals of each path to be amplified based on the received amplification commands and outputs the corresponding amplification factor to the multiplier stage amplifier circuit. Thus, the multiplier stage amplifier circuit can amplify the audio signals of each path to be amplified according to the amplification factor corresponding to each path and transmit the amplified audio signals of each path to the volume adjustment and power amplification circuit 105.

[0115] In addition, in the technical solution of this application, the frequency range (or frequency width) of the above M sound paths can be set according to the needs of the actual application scenario, so that the frequency width of each sound path is the same or different.

[0116] For example, as an example, in a preferred embodiment of this application, 100 sound paths (i.e., M is 100) can be set in the frequency range of 1Hz to 20000Hz, and the frequency width of each sound path is 200Hz; or 200 sound paths (i.e., M is 200) can be set in the frequency range of 1Hz to 20000Hz, and the frequency width of each sound path is 100Hz; ..., and so on.

[0117] For example, as an example, in a preferred embodiment of this application, 16 sound paths (i.e., M is 16) can be set in the frequency range of 50Hz to 8000Hz, and the frequency range of each sound path can be as follows:

[0118] The frequency range of the first acoustic path is 50Hz to 300Hz, with a center frequency of 175Hz.

[0119] The frequency range of the second acoustic path is 301Hz to 500Hz, with a center frequency of 400Hz.

[0120] The frequency range of the third acoustic path is 501Hz to 700Hz, with a center frequency of 600Hz.

[0121] The frequency range of the fourth acoustic path is 701Hz to 800Hz, with a center frequency of 750Hz.

[0122] The frequency range of the fifth acoustic path is 801Hz to 900Hz, with a center frequency of 850Hz.

[0123] The frequency range of the sixth acoustic path is 901Hz to 1000Hz, with a center frequency of 950Hz.

[0124] The frequency range of the 7th acoustic path is 1001Hz to 1200Hz, with a center frequency of 1100Hz.

[0125] The frequency range of the 8th acoustic path is 1201Hz to 1400Hz, with a center frequency of 1300Hz.

[0126] The frequency range of the 9th acoustic path is 1401Hz to 1600Hz, with a center frequency of 1500Hz.

[0127] The frequency range of the 10th acoustic path is 1601Hz to 2000Hz, with a center frequency of 1800Hz.

[0128] The frequency range of the 11th acoustic path is 2001Hz to 2500Hz, with a center frequency of 2250Hz.

[0129] The frequency range of the 12th acoustic path is 2501Hz to 3000Hz, with a center frequency of 2750Hz.

[0130] The frequency range of the 13th acoustic path is 3001Hz to 4000Hz, with a center frequency of 3500Hz.

[0131] The frequency range of the 14th acoustic path is 4001Hz to 5000Hz, with a center frequency of 4500Hz.

[0132] The frequency range of the 15th acoustic path is 5001Hz to 6500Hz, with a center frequency of 5750Hz.

[0133] The frequency range of the 16th acoustic path is 6501Hz to 8000Hz, with a center frequency of 7250Hz.

[0134] Furthermore, in the technical solution of this application, the width of the frequency range (i.e., frequency width or frequency density) can be referred to as the weight. For example, if the frequency range width of a sound path is X Hz, then the weight of that sound path can be X / 100. For instance, if the frequency range width of a sound path is 100 Hz, then the weight of that sound path can be 1; if the frequency range width of a sound path is 150 Hz, then the weight of that sound path can be 1.5; if the frequency range width of a sound path is 200 Hz, then the weight of that sound path can be 2; and so on.

[0135] Therefore, within the frequency range of 50Hz to 8000Hz, the aforementioned 16 sound paths each have their own frequency range and thus their own weights. For example, the weight of the first sound path is 2.5; the weights of the second, third, seventh, eighth, and ninth sound paths are 2; the weights of the fourth, fifth, and sixth sound paths are 1; the weight of the tenth sound path is 4; the weights of the eleventh and twelfth sound paths are 5; the weights of the thirteenth and fourteenth sound paths are 10; and the weights of the fifteenth and sixteenth sound paths are 15.

[0136] Generally, the higher the weight, the smaller the average gain error. The narrower the frequency bandwidth of the sound path, the higher the accuracy of the frequency compensation of the corresponding multi-order active bandpass filter. The audio signals around the center frequency in the sound path can be compensated as they should be, while the audio signals outside the upper and lower cutoff frequencies are amplified less. There are fewer audio signals in the sound path that do not need to be amplified, thus resulting in lower noise in the processed audio signal and better sound quality and timbre.

[0137] Within the aforementioned frequency range of 50Hz to 1600Hz, nine acoustic paths (corresponding to nine multi-order active bandpass filters) were configured, using an alternating weighting of 2.5, 2, 1, and 2. This configuration was chosen because, generally, the vocal range of Chinese men is between 82Hz and 700Hz, while that of women is between 82Hz and 1200Hz, and the vocal range of certain individuals can reach 1600Hz. Therefore, the 50Hz to 1600Hz frequency range can be designated as the key area for audio signals, with different frequency bandwidths assigned to each acoustic path for varying sound quality and timbre enhancement. This makes the 16-path hearing aid more suitable for Chinese hearing-impaired patients. Furthermore, some data suggests that foreigners have a slightly higher vocal range, reaching around 2000Hz; therefore, audio signals around 2000Hz can be processed in the overtone harmonic domain.

[0138] Therefore, in the above specific embodiment, 16 sound paths are set in the frequency range of 50Hz to 8000Hz, and 7 weighted frequency widths are used to suit various types of hearing-impaired patients or users.

[0139] In addition, in the technical solution of this application, the width (i.e., weight) of the frequency range of each sound path can be flexibly set according to the needs of the actual application scenario.

[0140] For example, as an example, in a preferred embodiment of this application, the width of the frequency range of any one or more sound paths can be set to 50Hz, then the weight of the sound path is 0.5; the width of the frequency range of any one or more sound paths can be set to 20Hz, then the weight of the sound path is 0.2; and so on, and will not be listed here one by one.

[0141] In the technical solution of this application, the number of sound paths and the frequency width of each sound path can be flexibly set according to the needs of the actual application scenario or the needs of each user. Therefore, the specific embodiments described above are only examples. In actual use, multiple sound paths can be set as needed, and the frequency width of each sound path can be set separately, which will not be listed here.

[0142] Furthermore, as an example, in one specific embodiment of this application, the address information of an acoustic path can also be set according to the center frequency of the acoustic path.

[0143] For example, the center frequency of a sound path can be set as the address information of that sound path; or, one or more characters can be added after or before the center frequency of a sound path as the address information of that sound path for address storage and retrieval.

[0144] Additionally, as an example, in a preferred embodiment of this application, the multi-order active bandpass filter can be a second-order, fourth-order, sixth-order, or eighth-order active bandpass filter, or other suitable multi-order active bandpass filters, which will not be listed here. Generally, the higher the order of the active bandpass filter, the faster the sound attenuates at the boundary of the passband, the narrower the boundary, the more obvious the frequency filtering effect, and the clearer the audio signal obtained after filtering.

[0145] Additionally, as an example, such as Figure 8 As shown, in a preferred embodiment of this application, when the multi-order active bandpass filter is a second-order active bandpass filter, the second-order active bandpass filter may include: a second-order active low-pass amplifier circuit and a second-order active high-pass amplifier circuit.

[0146] The second-order active low-pass amplifier circuit is used to perform low-pass filtering on the received audio signal and output the filtered signal to the second-order active high-pass amplifier circuit.

[0147] The second-order active high-pass amplifier circuit is used to perform high-pass filtering on the received audio signal and output the filtered audio signal to the multiplier stage configuration circuit.

[0148] The aforementioned second-order active low-pass amplifier circuit can perform low-pass filtering on the audio signal of its corresponding acoustic path, suppressing the corresponding high-frequency signals (the cutoff frequency of this second-order active low-pass amplifier circuit can be used as the upper cutoff frequency of the second-order active band-pass filter). Then, a second-order active high-pass amplifier circuit is used to perform high-pass filtering on the audio signal of its corresponding acoustic path, suppressing the corresponding low-frequency signals (the cutoff frequency of this second-order active high-pass amplifier circuit can be used as the lower cutoff frequency of the second-order active band-pass filter). Thus, only audio signals within a preset frequency range can pass through (the frequency range included by the upper and lower cutoff frequencies is the frequency range of the second-order active band-pass filter), thereby removing corresponding noise and interference and providing a clearer audio signal.

[0149] Additionally, as an example, in a preferred embodiment of this application, the multi-order active bandpass filter may include multiple second-order active bandpass filters.

[0150] For example, in one specific embodiment of this application, a fourth-order active bandpass filter may include two cascaded second-order active bandpass filters; a sixth-order active bandpass filter may include three cascaded second-order active bandpass filters; an eighth-order active bandpass filter may include four cascaded second-order active bandpass filters; and so on, without further listing.

[0151] Additionally, as an example, such as Figure 7 As shown, in a preferred embodiment of this application, the multiplier configuration circuit may include: a first eight-bit timer IC8-1, a second eight-bit counter IC8-2, and K multiplier resistors (e.g., R30-1 to R30-16);

[0152] The K multiplier resistors are connected in parallel; the first end of each multiplier resistor is connected to the output of the acoustic path configurator and an input of each acoustic path multiplier stage amplifier circuit, and the second end is connected to the first eight-bit timer IC8-1 and the second eight-bit counter IC8-2, respectively.

[0153] The first eight-bit timer IC8-1 and the second eight-bit counter IC8-2 are both eight-bit counters controlled by four-input binary pins;

[0154] The first eight-bit timer IC8-1 and the second eight-bit counter IC8-2 are connected in series to form a sixteen-bit counter (with series output);

[0155] The four input terminals of the first eight-bit timer IC8-1 and the second eight-bit counter IC8-2 (for example, the four parallel input terminals D0, D1, D2, D3, etc. shown in the figure) are connected one-to-one and respectively connected to the microcontroller 104 to form parallel input terminals.

[0156] In the technical solution of this application, the number of the above-mentioned multiple resistors, i.e., the value of K, can be preset according to the needs of the actual application scenario.

[0157] For example, as an example, in a preferred embodiment of this application, the value of K can be 4, 8, 16, 24, 48 or 56, or other suitable values, which will not be listed here.

[0158] In the specific embodiments described above in this application, the first 8-bit timer IC8-1 and the second 8-bit counter IC8-2 are connected in series to form a 16-bit counter with series output. The four input terminals of the first 8-bit timer IC8-1 and the second 8-bit counter IC8-2 can be used as four parallel input terminals of the 16-bit counter and connected to the microcontroller 104 respectively. Therefore, the microcontroller 104 can send amplification instructions to the two 8-bit counters through the above four parallel input terminals. The amplification instructions can carry address information (e.g., center frequency information of each audio path) and the serial number of the corresponding multiplier resistor, thereby controlling the two 8-bit counters to turn on the corresponding multiplier resistor according to the address information in the amplification instructions (e.g., the corresponding multiplier resistor can be grounded with a low level), so that only one multiplier resistor is turned on at the same time period, while the other multiplier resistors are in a non-conducting state. Therefore, when the corresponding multiplier resistor is turned on, it is equivalent to setting the corresponding amplification factor for the audio signal of the corresponding sound path; thus, the multiplier stage amplifier circuit can amplify the audio signal of each sound path by the corresponding multiplier according to the amplification factor corresponding to each sound path.

[0159] Additionally, as an example, in a preferred embodiment of this application, the microcontroller 104 can also be used to output clock pulse signals (e.g., output clock pulse signals to clock pin 14 of the first chip IC1) and reset pulse signals (e.g., output first reset pulse signals to clock pin 14 of the first chip IC1) to the automatic switching circuit 101.

[0160] Additionally, as an example, in a preferred embodiment of this application, the microcontroller 104 can output amplification instructions to the acoustic amplifier circuit 103 (e.g., output amplification instructions to the multiplier stage configuration circuit in the acoustic amplifier circuit 103) based on a preset configuration file (e.g., a sound path configuration library file) and the frequency band information of the audio signals of each sound path.

[0161] The configuration file includes the correspondence between each audio path and various amplification factors (e.g., the correspondence between each audio path and various multiplier resistors, or the correspondence between the frequency band information of the audio signal of each audio path and the serial number of each multiplier resistor, etc.).

[0162] Using the aforementioned preset configuration file, the microcontroller 104 can output an amplification command to the acoustic amplifier circuit 103, which carries information about the amplification factor corresponding to each acoustic path.

[0163] Furthermore, according to the pure-tone audiometry curves of deaf patients, a user's hearing generally declines as the audio frequency increases, and auditory ability is inversely proportional to the increase in audio frequency. Therefore, in the technical solution of this application, the aforementioned configuration file can be pre-set according to the needs of the actual application scenario.

[0164] For example, as an example, in a preferred embodiment of this application, the configuration file may be: a sound path configuration library generated based on the user's pure tone hearing threshold detection curve.

[0165] For example, as an example, in a preferred embodiment of this application, the required amplification factor (i.e., compensation factor) of the audio signal of each sound path can be calculated based on the user's pure tone hearing threshold detection curve during the fitting process, and a corresponding sound path configuration library can be generated based on the correspondence between the audio signal of each sound path and the amplification factor.

[0166] Therefore, in the technical solution of this application, a corresponding configuration file (equivalent to a configuration file customized for the user) can be generated according to the actual user of the hearing aid device, and the corresponding amplification command can be output to the multiplier configuration circuit according to the above configuration file. Thus, according to the actual user's specific hearing condition, the audio signal of the corresponding sound path can be amplified by a corresponding multiplier, the audio range suitable for the user can be adjusted accordingly, selective amplification and noise suppression can be performed, and the power of the amplified sound can be compensated according to different frequencies based on the user's pure tone hearing threshold detection curve, so that the sound in the sound path is compensated to the preset intensity range of the hearing threshold (e.g., 25dB, with a fluctuation of no more than 2.5dB), thereby enabling the actual user to hear a clearer sound signal through the hearing aid device.

[0167] For example, suppose that according to a user's pure-tone hearing threshold test curve, if the user's right ear requires 30 dB of sound pressure level (hereinafter referred to as SPL) to hear a 125 Hz sound, and 40 dB of SPL to hear a 250 Hz sound, then if the 125 Hz sound is amplified with the same 40 dB compensation power, the 125 Hz sound is amplified by 10 dB more, making it uncomfortable for the user to hear. Conversely, if the 250 Hz sound is amplified by 30 dB more than the 125 Hz sound, it is amplified by 10 dB less, making it difficult for the user to clearly hear the 250 Hz speech signal.

[0168] Furthermore, in the technical solution of this application, the configuration file in the microcontroller 104 can be modified or updated in real time according to the needs of the actual application scenario or the actual use effect, so that it can be easily upgraded and updated to achieve a better hearing compensation effect.

[0169] For example, as an example, in a preferred embodiment of this application, a sound path configuration library for the left ear and a sound path configuration library for the right ear can be generated based on the pure tone hearing threshold detection curve of the user's left ear and the pure tone hearing threshold detection curve of the right ear, respectively.

[0170] In practical applications, the hearing curves of the left and right ears of hearing-impaired patients may not be the same. Therefore, in the technical solution of this application, two independent sound path configuration libraries for the left and right ears can be used to compensate for sound separately, thus enabling individualized customization for specific users and effectively improving the stereo effect of sound to achieve higher sound resolution.

[0171] Additionally, as an example, in a preferred embodiment of this application, the configuration file can be located in the microcontroller 104 or in an external storage device (e.g., a memory card or other storage device).

[0172] Therefore, in the above specific embodiments of this application, the microcontroller 104 can read the correspondence between each acoustic path or frequency band and each multiplier resistor from the configuration file, and output amplification instructions to the acoustic path amplifier circuit 103 according to the correspondence.

[0173] For example, as an example, in a preferred embodiment of this application, the microcontroller 104 can start loading the memory card and read the serial number of the multiplier resistor corresponding to the frequency band information (e.g., the center frequency information of each audio path) of the audio signal of each audio path from the configuration file of the memory card. Then, it carries the corresponding address information (e.g., the center frequency information of each audio path) and the serial number of the corresponding multiplier resistor in the amplification instruction and sends them to the audio path amplification circuit 103, thereby controlling the two eight-bit counters to turn on the multiplier resistors with the corresponding serial numbers according to the address information in the amplification instruction.

[0174] Additionally, as an example, in a preferred embodiment of this application, the microcontroller 104 can also be used to control volume adjustment.

[0175] For example, as an example, in a preferred embodiment of this application, one end of the microcontroller 104 is connected to the volume up button and the volume down button respectively, and the other end is connected to the volume adjustment and power amplification circuit 105.

[0176] Therefore, when the volume up button is pressed, the microcontroller 104 receives a volume up signal and sends a volume up command to the volume adjustment and power amplification circuit 105 based on this signal; conversely, when the volume down button is pressed, the microcontroller 104 receives a volume down signal and sends a volume down command to the volume adjustment and power amplification circuit 105 based on this signal. The volume adjustment and power amplification circuit 105 can then increase or decrease the volume according to the received volume up or volume down command.

[0177] Additionally, as an example, in a preferred embodiment of this application, the microcontroller 104 can be connected to an external device (e.g., an external computer) via a serial port to obtain and update the program and configuration file in the microcontroller 104, thereby enabling the program update function after changes in hearing curves or product upgrades.

[0178] In summary, in the technical solution of this application, since the automatic switching circuit in the hearing aid is connected to N microphones in time periods and transmits the audio signals received by each microphone when connected to the automatic switching circuit to the automatic gain preamplifier circuit, N microphones can be used cyclically in different time periods to switch between different sound paths. This minimizes the repeated positive feedback of sound waves entering from the microphone, passing through the automatic gain preamplifier circuit, sound path amplification circuit, volume adjustment and power amplification circuit, and then reflecting back to the microphone. This results in the electronic amplification circuit lacking the necessary conditions for generating "circuit feedback," namely, the phase condition and oscillation amplitude—the two basic elements for generating feedback sound. Consequently, the sound waves in the electronic amplification circuit no longer possess [the necessary characteristics]. The system is equipped with self-excitation conditions, which can effectively suppress feedback. In addition, since the audio signal can be processed by an automatic gain preamplifier circuit, the intensity of the processed audio signal is within a preset intensity range (for example, about 25 dB). Then, the audio signal is divided into multiple audio paths according to frequency bands by a sound path amplification circuit. According to the amplification instructions sent by the microcontroller, the audio signal of each audio path is amplified by different amplification factors. Therefore, the audio signal within the user's hearing frequency range can be effectively amplified in a targeted manner, while other noise signals are effectively suppressed. This makes it easier for the user to hear the sound content in the audio signal clearly, and can also effectively improve the sound quality of the audio signal, thereby enhancing the user experience.

[0179] Furthermore, the aforementioned hearing aid device in this application can also be customized for individual users, thereby effectively improving the stereo effect of sound and achieving higher sound resolution.

[0180] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the scope of protection of the present utility model.

Claims

1. An assistive hearing device, characterized in that, The hearing aid includes: an automatic switching circuit, an automatic gain preamplifier circuit, an acoustic path amplifier circuit, a microcontroller, a volume adjustment and power amplification circuit, and N microphones; where N is an integer greater than or equal to N. The automatic switching circuit is used to connect N microphones to the automatic gain preamplifier circuit in time periods, and transmit the audio signals received by each microphone during its connected time period to the automatic gain preamplifier circuit. The automatic gain preamplifier circuit is used to process the received audio signal so that the intensity of the processed audio signal is within a preset intensity range, and to transmit the processed audio signal to the acoustic path amplifier circuit. The microcontroller is used to send amplification instructions to the acoustic path amplification circuit, and the amplification instructions include amplification factor information corresponding to multiple acoustic paths; The sound path amplification circuit is used to divide the received audio signal into multiple sound paths according to the frequency band; according to the received amplification command, the audio signal of each sound path is amplified respectively, and the amplified audio signal of each sound path is transmitted to the volume adjustment and power amplification circuit. The volume adjustment and power amplification circuit is used to adjust the volume of the received audio signal according to the received adjustment command, and output the adjusted audio signal.

2. The hearing aid device according to claim 1, characterized in that, The automatic switching circuit includes: a first chip and a second chip; The first chip is used to send switch control signals corresponding to N microphones to the second chip according to the received clock pulse signal; The N microphones are respectively connected to the second chip; The second chip is used to turn the corresponding microphone on or off according to the received switch control signal, connect the N microphones to the automatic gain preamplifier circuit in time periods, and transmit the audio signals received by each microphone during its connected time period to the automatic gain preamplifier circuit.

3. The hearing aid device according to claim 2, characterized in that: The first chip is also used to receive a first reset pulse signal and a second reset pulse signal; to perform a global reset according to the first reset pulse signal; and to perform a cyclic reset according to the second reset pulse signal.

4. The hearing aid device according to claim 3, characterized in that, When 3 microphones are set: The first chip has a clock pin, a reset pin, and four analog switch pins. The second chip has 4 control pins, 4 microphone pins, and 4 output pins; wherein the 4 analog switch pins, 4 control pins, 4 microphone pins, and 4 output pins correspond one-to-one. Two of the three microphones are connected at one end to one microphone pin on the second chip, and the other microphone is connected at one end to two microphone pins on the second chip. The clock pin of the first chip is used to receive clock pulse signals; The reset pin of the first chip is used to receive a first reset pulse signal and a second reset pulse signal; The four analog switch pins on the first chip are connected one-to-one with the four control pins on the second chip, and are used to send switch control signals to the corresponding control pins of the second chip according to the clock pulse signal. The four control pins on the second chip are used to send the received switch control signals to the corresponding microphone pins. The four microphone pins on the second chip are connected one-to-one with the four output pins, which are used to turn the connected microphone on or off according to the received switch control signal, and to transmit the audio signal received by the connected microphone during the time period when it is turned on to the corresponding output pin. The four output pins on the second chip are all connected to the microphone signal bus, and the received audio signal is transmitted to the automatic gain preamplifier circuit through the microphone signal bus and the third coupling capacitor.

5. The hearing aid device according to claim 1 or 2, characterized in that, The automatic gain preamplifier circuit includes: a third chip, a fourth chip, a fifth chip, and a voltage divider circuit; The first input terminal of the third chip is connected to the output terminal of the automatic conversion circuit; the output terminal of the third chip is connected to one input terminal of the fourth chip. The first output terminal of the fourth chip is connected to one input terminal of the fifth chip; the second output terminal of the fourth chip is connected to the acoustic amplifier circuit. The output terminal of the fifth chip is connected to the second input terminal of the third chip; The third chip is used to transmit the audio signal received from the first input terminal to the fourth chip, calculate the product of the signals received from the first input terminal and the second input terminal, and output the product as a gain value to the fourth chip. The fourth chip is used to amplify the received audio signal in the first stage according to the received gain value; when the intensity of the amplified signal is within a preset intensity range, the amplified signal is output to the acoustic path amplifier circuit; when the intensity of the amplified signal is not within the preset intensity range, the amplified signal is rectified and output to the fifth chip. The voltage divider circuit includes: a first adjustable voltage divider resistor and a second adjustable voltage divider resistor; the first end of the first adjustable voltage divider resistor is connected to the power supply, and the second end is connected to the first end of the second adjustable voltage divider resistor and the fifth chip; the second end of the second adjustable voltage divider resistor is grounded. The fifth chip is used to perform low-pass filtering on the received signal, determine the corresponding amplification factor according to the voltage output of the voltage divider circuit, and perform a second-stage amplification on the low-pass filtered signal according to the determined amplification factor before outputting it to the third chip.

6. The hearing aid device according to claim 5, characterized in that, The fourth chip includes: a first-stage amplifier circuit and a precision rectifier circuit; One input terminal of the first-stage amplifier circuit is connected to the output terminal of the third chip; the output terminal of the first-stage amplifier circuit is connected to one input terminal of the precision rectifier circuit and the input terminal of the acoustic path amplifier circuit, respectively. The output terminal of the precision rectifier circuit is connected to the input terminal of the fifth chip; The first-stage amplifier circuit is used to amplify the received audio signal according to the received gain value; when the intensity of the amplified signal is within a preset intensity range, the amplified signal is output to the acoustic path amplifier circuit; when the intensity of the amplified signal is not within the preset intensity range, the amplified signal is output to the precision rectifier circuit. The precision rectifier circuit is used to rectify the received signal and output the rectified signal to the fifth chip.

7. The hearing aid device according to claim 5, characterized in that, The fifth chip includes: a first-order active filter circuit and a second-stage amplifier circuit; One input terminal of the first-order active filter circuit is connected to the first output terminal of the fourth chip, and the output terminal of the first-order active filter circuit is connected to the first input terminal of the second-stage amplifier circuit. The second input terminal of the second-stage amplifier circuit is connected to the output terminal of the voltage divider circuit; the output terminal of the second-stage amplifier circuit is connected to the second input terminal of the third chip. The first-order active filter circuit is used to perform low-pass filtering on the received signal and output the low-pass filtered signal to the second-stage amplifier circuit. The second-stage amplifier circuit is used to determine the corresponding amplification factor based on the voltage output by the voltage divider circuit, and then amplify the low-pass filtered signal according to the determined amplification factor before outputting it to the third chip.

8. The hearing aid device according to claim 1, characterized in that, The acoustic path amplifier circuit includes: M multi-order active bandpass filters, an acoustic path configurator, a multiplier stage configuration circuit, and each acoustic path multiplier stage amplifier circuit; The M multi-stage active bandpass filters are used to perform low-pass filtering and high-pass filtering on the received audio signal respectively, divide the received audio signal into M audio signals according to frequency band, and output the filtered audio signal to the audio path configurator. The sound path configurator is used to output the received audio signals from each sound path to the multiplier configuration circuit, record the frequency band information of the audio signals from each sound path, and output the recorded frequency band information to the microcontroller. The multiplier stage configuration circuit is used to determine the amplification factor corresponding to the audio signal of each received sound path according to the received amplification instruction, and output the corresponding amplification factor to the multiplier stage amplification circuit respectively. The multiplier stage amplifier circuit is used to amplify the received audio signals of each audio path according to the amplification factor corresponding to each audio path, and transmit the amplified audio signals of each audio path to the volume adjustment and power amplification circuit.

9. The hearing aid device according to claim 8, characterized in that: Set the frequency range of the M sound paths so that the frequency width of each sound path is the same or different.

10. The hearing aid device according to claim 8, characterized in that: The multi-order active bandpass filter is a second-order active bandpass filter, a fourth-order active bandpass filter, a sixth-order active bandpass filter, or an eighth-order active bandpass filter. The second-order active bandpass filter includes: a second-order active low-pass amplifier circuit and a second-order active high-pass amplifier circuit. The second-order active low-pass amplifier circuit is used to perform low-pass filtering on the received audio signal and output the filtered signal to the second-order active high-pass amplifier circuit. The second-order active high-pass amplifier circuit is used to perform high-pass filtering on the received audio signal and output the filtered audio signal to the multiplier stage configuration circuit.

11. The hearing aid device according to claim 8, characterized in that, The multiplier-level configuration circuit includes: a first eight-bit timer, a second eight-bit counter, and K multiplier resistors; The K multiplier resistors are connected in parallel; the first end of each multiplier resistor is connected to the output of the acoustic path configurator and an input of each acoustic path multiplier stage amplifier circuit, and the second end is connected to the first eight-bit timer and the second eight-bit counter, respectively. Both the first eight-bit timer and the second eight-bit counter are eight-bit counters controlled by four-input binary. The first eight-bit timer and the second eight-bit counter are connected in series to form a sixteen-bit counter; The four input terminals of the first eight-bit timer and the second eight-bit counter are connected one-to-one and respectively connected to the microcontroller to form parallel input terminals.

12. The hearing aid device according to claim 1, characterized in that: The microcontroller outputs amplification commands to the sound path amplifier circuit according to the preset configuration file and the frequency band information of the audio signals of each sound path; the configuration file includes the correspondence between each sound path and various amplification factors.

13. The hearing aid device according to claim 12, characterized in that, The configuration file is as follows: A sound path configuration library generated based on the user's pure tone hearing threshold detection curve.

14. The hearing aid device according to claim 13, characterized in that: Based on the pure tone hearing threshold test curves of the user's left and right ears, a sound path configuration library for the left ear and a sound path configuration library for the right ear are generated respectively.

15. The hearing aid device according to claim 1, characterized in that: The microcontroller is also used to control volume adjustment; One end of the microcontroller is connected to the volume up button and the volume down button, respectively, and the other end is connected to the volume adjustment and power amplification circuit.

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