A multi-channel WDRC hearing aid and circuit therefor

Abstract

The utility model relates to the field of hearing aid. The utility model discloses a kind of multi-channel WDRC hearing aid and its circuit, multi-channel WDRC hearing aid circuit includes: main control module, touch module, microphone module, charge management module, battery protection module, LDO module, lithium battery and LED module, main control module includes main control chip U3, battery protection module includes charge and discharge positive electrode pin BAT+ and charge and discharge negative electrode pin BAT-, the positive and negative pole of lithium battery is respectively electrically connected the charge and discharge positive electrode pin BAT+ and charge and discharge negative electrode pin BAT- of battery protection module, charge management module, lithium battery, LDO module, touch module and LED module are all electrically connected in charge and discharge positive electrode pin BAT+, main control chip U3 and microphone module are all connected in LDO module, touch module, microphone module and LDO module are all electrically connected in main control chip U3. The utility model can touch control volume size, can flexibly configure gain size, with lithium battery, it is convenient to carry and charge, so as to adapt to different hearing loss crowd.

Description

Technical Field

[0001] This utility model relates to the field of hearing aids, and in particular to a multi-channel WDRC hearing aid and its circuit. Background Technology

[0002] A hearing aid is a small amplifier that amplifies sounds that are otherwise inaudible, allowing the residual hearing of the hearing-impaired person to transmit the sound to the auditory center of the brain, thus enabling them to perceive the sound. It mainly consists of five parts: a sound inlet, amplifier, earpiece, power supply, and volume control. Hearing aids are classified according to their conduction method into air conduction hearing aids and bone conduction hearing aids; and according to their usage method into body-worn, eyeglass-style, hair clip-on, behind-the-ear, in-the-ear, in-the-canal, and fully-in-the-canal hearing aids.

[0003] Buttons, wheels, or touch controls for hearing aids are often located on the hearing aid itself. Due to the small size of hearing aids, these buttons, wheels, or touch controls are also relatively small. Since most hearing aid users are elderly, their physical limitations make it difficult for them to accurately control these buttons, wheels, or touch controls. If an elderly person accidentally touches a button or wheel, causing the volume to amplify, the excessively loud output sound can damage their hearing.

[0004] The world today is moving towards digitalization, intelligence, programmable technology, and high-tech fields. Therefore, this invention addresses the needs of the times by proposing a conveniently rechargeable multi-channel WDRC hearing aid and its circuitry. It allows for touch control of the hearing aid's volume, flexible configuration of volume gain, and adjustment of the maximum output limit to prevent excessive sound from damaging the hearing of the elderly. It also features a built-in lithium battery for easy portability and charging. Utility Model Content

[0005] The purpose of this invention is to provide a multi-channel WDRC hearing aid circuit to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model adopts the following technical solution: a multi-channel WDRC hearing aid circuit, comprising: a main control module, a touch module, a microphone module, a charging management module, a battery protection module, an LDO module, a lithium battery, and an LED module. The main control module includes a main control chip U3. The battery protection module includes a charging / discharging positive terminal pin BAT+ and a charging / discharging negative terminal pin BAT-. The positive and negative terminals of the lithium battery are electrically connected to the charging / discharging positive terminal pin BAT+ and the charging / discharging negative terminal pin BAT- of the battery protection module, respectively. The charging management module, lithium battery, LDO module, touch module, and LED module are all electrically connected to the charging / discharging positive terminal pin BAT+. The main control chip U3 and the microphone module are both connected to the LDO module. The touch module, microphone module, and LDO module are all electrically connected to the main control chip U3.

[0007] Preferably, the charging management module includes a charging management chip U1, a light-emitting diode LED1, resistors R5 and R10, a capacitor C4, a positive charging port CH+, and a negative charging port CH-. The positive charging port CH+ and the negative charging port CH- are respectively connected to the VIN pin and GND pin of the charging management chip U1. The two ends of the capacitor C4 are respectively connected to the VIN pin and GND pin of the charging management chip U1. The two ends of the resistor R10 are respectively connected to the GND pin and PROG pin of the charging management chip U1. The two ends of the resistor R5 are respectively connected to the VIN pin of the charging management chip U1 and the positive terminal of the light-emitting diode LED1. The negative terminal of the light-emitting diode LED1 is connected to the CHGB pin of the charging management chip U1. The BAT pin of the charging management chip U1 is connected to the positive charging / discharging pin BAT+.

[0008] Preferably, the battery protection module further includes a battery protection chip U2, a resistor R8, and a capacitor C7. The resistor R8 is electrically connected between the positive charging / discharging pin BAT+ and the VDD pin of the battery protection chip U2. The negative charging / discharging pin BAT- is electrically connected to the ED pin of the battery protection chip U2. The two ends of the capacitor C7 are respectively connected to the VDD pin and the ED pin of the battery protection chip U2.

[0009] Preferably, the LDO module includes a voltage regulator chip U4, a Hall effect chip U5, capacitors C16 and C17. The VIN pin of the voltage regulator chip U4 and the VDD pin of the Hall effect chip U5 are both electrically connected to the positive charging / discharging pin BAT+. The OUT pin of the Hall effect chip U5 is electrically connected to the enable pin EN of the voltage regulator chip U4. The two ends of the capacitor C16 are respectively connected to the VOUT pin and the GND pin of the voltage regulator chip U4. The two ends of the capacitor C17 are respectively connected to the VOUT pin and the GND pin of the voltage regulator chip U4.

[0010] Preferably, the main control module further includes capacitors C3, C5, C11, and C13. The VDD_IO and AVDD pins of the main control chip U3 are both electrically connected to the VOUT pin of the voltage regulator chip U4. Capacitor C3 is connected between the AVDD and AGND pins of the main control chip U3. Capacitor C5 is connected between the VDD_ANA and AGND pins of the main control chip U3. Capacitor C11 is connected between the DVDD pin of the main control chip U3 and ground. Capacitor C13 is connected between the VDD_CORE and DGND pins of the main control chip U3.

[0011] Preferably, the microphone module includes a MEMS microphone chip, capacitor C19, and capacitor C20. The two ends of capacitor C19 are respectively connected to the OUT pin of the MEMS microphone chip and the MIC0 pin of the main control chip U3. The VDD pin of the MEMS microphone chip is electrically connected to the VOUT pin of the voltage regulator chip U4. One end of capacitor C20 is connected between the VDD pin of the MEMS microphone chip and the VOUT pin of the voltage regulator chip U4. The other end of capacitor C20 and the GND pin of the MEMS microphone chip are both electrically connected to the AGND pin of the main control chip U3.

[0012] Preferably, the touch module includes a touch chip U6, capacitors C1 and C2. The OUT pin of the touch chip U6 is electrically connected to the V_CHK2 pin of the main control chip U3. The charging / discharging positive pin BAT+ is electrically connected to the VDD pin of the touch chip U6. One end of each of the capacitors C1 and C2 is grounded. The other end of the capacitor C2 is connected between the charging / discharging positive pin BAT+ and the VDD pin of the touch chip U6. The other end of the capacitor C1 is connected to the touch input terminal of the touch chip U6.

[0013] Preferably, the LED module includes a transistor Q1, a resistor R3, a resistor R4, and a light-emitting diode LED2. The resistor R3 is connected between the charging / discharging positive pin BAT+ and the positive terminal of the light-emitting diode LED2. The negative terminal of the light-emitting diode LED2 is electrically connected to the collector of the transistor Q1. The resistor R4 is connected between the base of the transistor Q1 and the GPIO4 pin of the main control chip U3. The emitter of the transistor Q1 is grounded.

[0014] Preferably, the main control module further includes a UART serial communication port and a resistor R9. The resistor R9 is connected between the VOUT pin of the voltage regulator chip U4 and the GPIO0 pin of the main control chip U3. The GPIO2 pin of the main control chip U3 and the input terminal of the UART serial communication port are both electrically connected between the resistor R9 and the GPIO0 pin of the main control chip U3.

[0015] This utility model also provides a multi-channel WDRC hearing aid, which includes a first shell, a hollow tube, and a second shell connected in sequence. The hollow tube is bent into a U-shape. The first shell contains a circuit board and a lithium battery. The circuit board contains the multi-channel WDRC hearing aid circuit as described above. The second shell contains a speaker. The hollow tube contains a positive wire and a negative wire. The two ends of the positive wire are electrically connected to the positive terminal of the speaker and the SDMP pin of the main control chip U3, respectively. The two ends of the negative wire are electrically connected to the negative terminal of the speaker and the SDMN pin of the main control chip U3, respectively.

[0016] The beneficial effects of this utility model are as follows: This utility model provides a programmable multi-channel WDRC frequency domain hearing aid (up to 16 channels), which can control the volume by touch, can flexibly configure the gain, has a built-in lithium battery, is easy to carry and charge, so as to adapt to people with different hearing loss. Attached Figure Description

[0017] The accompanying drawings further illustrate the present invention, but the embodiments in the drawings do not constitute any limitation on the present invention.

[0018] Figure 1 A schematic diagram of a multi-channel WDRC hearing aid circuit provided in an embodiment of this utility model; Figure 2 A circuit diagram of a charging management module provided in an embodiment of this utility model; Figure 3 A circuit diagram of a battery protection module provided in an embodiment of this utility model; Figure 4 A circuit diagram of the main control module provided in one embodiment of this utility model; Figure 5 A circuit diagram of an LDO module provided in an embodiment of this utility model; Figure 6 A circuit diagram of a touch module provided in an embodiment of this utility model; Figure 7 A circuit diagram of a microphone module provided in an embodiment of the present invention; Figure 8 A circuit diagram of an LED module provided in an embodiment of this utility model; Figure 9 This is a schematic diagram of the structure of a multi-channel WDRC hearing aid provided in an embodiment of the present invention; In the diagram, the markings are: 11: First outer casing; 12: Second outer casing; 13: Hollow tube; 14: Speaker; 15: Circuit board; 16: Lithium battery. Detailed Implementation

[0019] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.

[0020] It should be noted that, in this utility model, unless otherwise stated, when an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element present at the same time.

[0021] like Figures 1 to 8As shown in the figure, an embodiment of this utility model provides a multi-channel WDRC (Wide Dynamic Range Compression) hearing aid circuit, including: a main control module, a touch module, a microphone module, a charging management module, a battery protection module, an LDO module, a lithium battery, and an LED module. The main control module includes a main control chip U3. The battery protection module includes a charging / discharging positive terminal pin BAT+ and a charging / discharging negative terminal pin BAT-. The positive and negative terminals of the lithium battery are electrically connected to the charging / discharging positive terminal pin BAT+ and the charging / discharging negative terminal pin BAT- of the battery protection module, respectively. The charging management module, lithium battery, LDO module, touch module, and LED module are all electrically connected to the charging / discharging positive terminal pin BAT+. The main control chip U3 and the microphone module are both connected to the LDO module. The touch module, microphone module, and LDO module are all electrically connected to the main control chip U3. The charging management module powers on the charging compartment and provides charging current and voltage to the battery protection module. The battery protection module protects and controls the charging and discharging of the lithium battery. The lithium battery provides 4.2V. The LDO module converts the 4.2V from the lithium battery to 1.8V and supplies it to other loads. The LED module indicates battery level; it turns off when the battery is low. The microphone module receives ambient sound signals from the user and converts them into electrical signals. The touch module senses touch signals from the user and converts them into electrical signals. The main control module receives and processes the electrical signals from the microphone and touch modules. The microphone signal is amplified by the main control module and output to the speaker. The touch module's output signal controls the amplification factor of the hearing aid, adjusting the volume after amplification. The main control module adjusts the amplification factor based on the number of touches detected by the touch module per unit time.

[0022] like Figure 2As shown, the charging management module includes a charging management chip U1, a light-emitting diode (LED) LED1, resistors R5 and R10, a capacitor C4, a positive charging port CH+, and a negative charging port CH-. The positive charging port CH+ and the negative charging port CH- are connected to the VIN and GND pins of the charging management chip U1, respectively. The two ends of capacitor C4 are connected to the VIN and GND pins of the charging management chip U1, respectively. The two ends of resistor R10 are connected to the GND and PROG pins of the charging management chip U1, respectively. The two ends of resistor R5 are connected to the VIN pin of the charging management chip U1 and the positive terminal of the LED1, respectively. The negative terminal of the LED1 is connected to the CHGB pin of the charging management chip U1. The BAT pin of the charging management chip U1 is connected to the positive charging / discharging pin BAT+. The charging management chip U1 is an HP4059 model. Both the positive charging port CH+ and the negative charging port CH- are copper pillars or copper sheets. The positive charging port CH+ and the negative charging port CH- are electrically connected to copper pins inside the charging compartment. The charging management chip U1 controls the charging current and voltage to a safe level, thereby achieving constant current and constant voltage charging. LED1 indicates whether the hearing aid is charging.

[0023] In one embodiment, such as Figure 2 As shown, the charging management module also includes a bidirectional breakdown diode ESD1. One end of the bidirectional breakdown diode ESD1 is connected between the VIN pin of the charging management chip U1 and the positive charging port CH+, and the other end of the bidirectional breakdown diode ESD1 is grounded. The bidirectional breakdown diode provides ESD protection, surge protection, and prevents excessive current and voltage.

[0024] like Figure 3 As shown, the battery protection module also includes a battery protection chip U2, a resistor R8, and a capacitor C7. The resistor R8 is electrically connected between the positive charging / discharging pin BAT+ and the VDD pin of the battery protection chip U2. The negative charging / discharging pin BAT- is electrically connected to the ED pin of the battery protection chip U2. The two ends of the capacitor C7 are connected to the VDD pin and the ED pin of the battery protection chip U2, respectively. The battery protection chip U2 is a CM2124 lithium battery protection IC. The battery protection chip U2 monitors and protects the lithium battery, preventing overcharging, over-discharging, and short circuits, ensuring battery safety and stability.

[0025] like Figure 5As shown, the LDO module includes a voltage regulator chip U4, a Hall effect chip U5, capacitors C16 and C17. The VIN pin of the voltage regulator chip U4 and the VDD pin of the Hall effect chip U5 are both electrically connected to the positive charging / discharging pin BAT+. The OUT pin of the Hall effect chip U5 is electrically connected to the enable pin EN of the voltage regulator chip U4. The two ends of capacitor C16 are connected to the VOUT pin and GND pin of the voltage regulator chip U4, respectively. The two ends of capacitor C17 are also connected to the VOUT pin and GND pin of the voltage regulator chip U4, respectively. The voltage regulator chip U4 is a model RT9073-1.8V LDO voltage regulator chip. The Hall effect chip U5 is a model AS1510 Hall effect switch. When the Hall effect switch senses the magnetic field generated by the permanent magnet inside the charging case, it controls the voltage regulator chip U4 to cut off the power, thus automatically powering off the hearing aid.

[0026] like Figure 4 As shown, the main control module also includes capacitors C3, C5, C11, and C13. The VDD_IO and AVDD pins of the main control chip U3 are both electrically connected to the VOUT pin of the voltage regulator chip U4. Capacitor C3 is connected between the AVDD and AGND pins of the main control chip U3. Capacitor C5 is connected between the VDD_ANA and AGND pins of the main control chip U3. Capacitor C11 is connected between the DVDD pin and ground of the main control chip U3. Capacitor C13 is connected between the VDD_CORE and DGND pins of the main control chip U3. Filtering is achieved by connecting capacitors C3 and C5 to the analog ground of the main control chip U3.

[0027] like Figure 7 As shown, the microphone module includes a MEMS microphone chip, capacitor C19, and capacitor C20. The two ends of capacitor C19 are connected to the OUT pin of the MEMS microphone chip and the MIC0 pin of the main control chip U3, respectively. The VDD pin of the MEMS microphone chip is electrically connected to the VOUT pin of the voltage regulator chip U4. One end of capacitor C20 is connected between the VDD pin of the MEMS microphone chip and the VOUT pin of the voltage regulator chip U4. The other end of capacitor C20 and the GND pin of the MEMS microphone chip are both electrically connected to the AGND pin of the main control chip U3. The MEMS microphone chip is a ZTS6216 model. A small MEMS microphone chip is used to collect sound signals and convert them into electrical signals for transmission to the main control chip U3, achieving back-end sound input.

[0028] like Figure 6As shown, the touch module includes a touch chip U6, capacitors C1 and C2. The OUT pin of the touch chip U6 is electrically connected to the V_CHK2 pin of the main control chip U3, and the charging / discharging positive pin BAT+ is electrically connected to the VDD pin of the touch chip U6. One end of each capacitor C1 and C2 is grounded, and the other end of capacitor C2 is connected between the charging / discharging positive pin BAT+ and the VDD pin of the touch chip U6. The other end of capacitor C1 is connected to the touch input terminal of the touch chip U6. The touch chip U6 is configured as a VM8211C touch sensor. The touch chip U6 senses the touch signal from a human hand and transmits the touch signal to the main control chip U3. The user controls the volume by touching the touch chip U6.

[0029] like Figure 8 As shown, the LED module includes a transistor Q1, resistors R3 and R4, and a light-emitting diode LED2. Resistor R3 is connected between the positive charging / discharging pin BAT+ and the positive terminal of LED2. The negative terminal of LED2 is electrically connected to the collector of transistor Q1. Resistor R4 is connected between the base of transistor Q1 and the GPIO4 pin of the main control chip U3. The emitter of transistor Q1 is grounded. Transistor Q1 is an NPN transistor. When the battery power is sufficient for normal use, the battery provides a high-level signal, causing transistor Q1 to saturate and conduct, lighting LED2. When the battery power is insufficient for normal use, the battery provides a low-level signal, causing transistor Q1 to cut off, and LED2 to turn off.

[0030] like Figure 4 As shown, the main control module also includes a UART serial communication port and a resistor R9. Resistor R9 is connected between the VOUT pin of the voltage regulator chip U4 and the GPIO0 pin of the main control chip U3. The GPIO2 pin of the main control chip U3 and the input terminal of the UART serial communication port are both electrically connected between resistor R9 and the GPIO0 pin of the main control chip U3. The host computer and the main control chip U3 communicate via the UART serial communication protocol. The host computer can programmatically adjust the parameters of the quiet compression zone, the loud compression zone, the gain parameter, and the compression ratio to make the loud amplification ratio smaller and the quiet amplification ratio larger. Additionally, the maximum output limiting function of the hearing aid can be adjusted via the host computer to prevent excessive output sound from damaging hearing. Different electroacoustic parameters can be adjusted through software without changing the hardware to suit people with different hearing losses, improving R&D and production efficiency and reducing production costs.

[0031] In one embodiment, such as Figure 4As shown, the main control module also includes capacitor C15, which is connected between the EN pin and the RESET pin of the main control chip U3. This enables the main control chip U3 to automatically restart.

[0032] In one embodiment, such as Figure 4 As shown, the main control module further includes capacitors C8, C9, C10, and C12. Capacitor C8 is connected between the VBN_LN pin and the DGND pin of the main control chip U3; capacitor C9 is connected between the VREF_LN pin and the DGND pin of the main control chip U3; capacitor C10 is connected between the ANA0 pin and the DGND pin of the main control chip U3; and capacitor C12 is connected between the AVB pin and the DGND pin of the main control chip U3. Capacitors C8, C9, C10, and C12 are all connected to the digital ground line of the main control chip.

[0033] In one embodiment, the main control module further includes a voltage divider resistor. One end of the voltage divider resistor is connected between the base of transistor Q1 and resistor R4, and the other end of the voltage divider resistor is connected between the emitter of transistor Q1 and ground. By dividing the voltage through the voltage divider resistor, it is ensured that when the light-emitting diode LED2 is at a low level, transistor Q1 has not reached its turn-on voltage.

[0034] like Figure 9 As shown, this utility model also provides a multi-channel WDRC hearing aid, which includes a first outer shell 11, a hollow tube 13, and a second outer shell 12 connected in sequence. The hollow tube 13 is bent into a U-shape. The first outer shell 11 houses a circuit board 15 and a lithium battery 16. The circuit board 15 has a multi-channel WDRC hearing aid circuit as described in the above embodiment. The second outer shell 12 houses a speaker 14. The hollow tube has a positive wire and a negative wire. The two ends of the positive wire are electrically connected to the positive terminal of the speaker 14 and the SDMP pin of the main control chip U3, respectively. The two ends of the negative wire are electrically connected to the negative terminal of the speaker 14 and the SDMN pin of the main control chip U3, respectively. The hollow tube 13 is used to clip onto the user's ear, with the second outer shell 12 facing the ear canal and the first outer shell 11 located behind the ear. The multi-channel WDRC hearing aid circuit inside the first outer shell 11 collects sound signals, amplifies them, and transmits them to the speaker 14 inside the first outer shell 11. The lithium battery 16 is a 1040A button cell lithium battery.

[0035] The technical features of the embodiments described above can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this utility model, and these should all be considered to be within the scope of this specification.

Claims

1. A multi-channel WDRC hearing aid circuit, characterized in that: include: The system includes a main control module, a touch module, a microphone module, a charging management module, a battery protection module, an LDO module, a lithium battery, and an LED module. The main control module includes a main control chip U3. The battery protection module includes a positive charging / discharging pin BAT+ and a negative charging / discharging pin BAT-. The positive and negative terminals of the lithium battery are electrically connected to the positive charging / discharging pin BAT+ and the negative charging / discharging pin BAT- of the battery protection module, respectively. The charging management module, lithium battery, LDO module, touch module, and LED module are all electrically connected to the positive charging / discharging pin BAT+. The main control chip U3 and the microphone module are both connected to the LDO module. The touch module, microphone module, and LDO module are all electrically connected to the main control chip U3.

2. The multi-channel WDRC hearing aid circuit according to claim 1, characterized in that: The charging management module includes a charging management chip U1, a light-emitting diode (LED1), resistors R5 and R10, a capacitor C4, a positive charging port CH+, and a negative charging port CH-. The positive charging port CH+ and the negative charging port CH- are connected to the VIN pin and GND pin of the charging management chip U1, respectively. The two ends of the capacitor C4 are connected to the VIN pin and GND pin of the charging management chip U1, respectively. The two ends of the resistor R10 are connected to the GND pin and PROG pin of the charging management chip U1, respectively. The two ends of the resistor R5 are connected to the VIN pin of the charging management chip U1 and the positive terminal of the LED1, respectively. The negative terminal of the LED1 is connected to the CHGB pin of the charging management chip U1. The BAT pin of the charging management chip U1 is connected to the positive charging / discharging pin BAT+.

3. The multi-channel WDRC hearing aid circuit according to claim 1, characterized in that: The battery protection module also includes a battery protection chip U2, a resistor R8, and a capacitor C7. The resistor R8 is electrically connected between the positive charging / discharging pin BAT+ and the VDD pin of the battery protection chip U2. The negative charging / discharging pin BAT- is electrically connected to the ED pin of the battery protection chip U2. The two ends of the capacitor C7 are respectively connected to the VDD pin and the ED pin of the battery protection chip U2.

4. The multi-channel WDRC hearing aid circuit according to claim 1, characterized in that: The LDO module includes a voltage regulator chip U4, a Hall effect chip U5, capacitors C16 and C17. The VIN pin of the voltage regulator chip U4 and the VDD pin of the Hall effect chip U5 are both electrically connected to the positive charging / discharging pin BAT+. The OUT pin of the Hall effect chip U5 is electrically connected to the enable pin EN of the voltage regulator chip U4. The two ends of the capacitor C16 are connected to the VOUT pin and the GND pin of the voltage regulator chip U4, respectively. The two ends of the capacitor C17 are connected to the VOUT pin and the GND pin of the voltage regulator chip U4, respectively.

5. The multi-channel WDRC hearing aid circuit according to claim 4, characterized in that: The main control module also includes capacitors C3, C5, C11, and C13. The VDD_IO and AVDD pins of the main control chip U3 are both electrically connected to the VOUT pin of the voltage regulator chip U4. Capacitor C3 is connected between the AVDD and AGND pins of the main control chip U3. Capacitor C5 is connected between the VDD_ANA and AGND pins of the main control chip U3. Capacitor C11 is connected between the DVDD pin of the main control chip U3 and ground. Capacitor C13 is connected between the VDD_CORE and DGND pins of the main control chip U3.

6. The multi-channel WDRC hearing aid circuit according to claim 1, characterized in that: The microphone module includes a MEMS microphone chip, capacitor C19, and capacitor C20. The two ends of capacitor C19 are connected to the OUT pin of the MEMS microphone chip and the MIC0 pin of the main control chip U3, respectively. The VDD pin of the MEMS microphone chip is electrically connected to the VOUT pin of the voltage regulator chip U4. One end of capacitor C20 is connected between the VDD pin of the MEMS microphone chip and the VOUT pin of the voltage regulator chip U4. The other end of capacitor C20 and the GND pin of the MEMS microphone chip are both electrically connected to the AGND pin of the main control chip U3.

7. The multi-channel WDRC hearing aid circuit according to claim 1, characterized in that: The touch module includes a touch chip U6, capacitors C1 and C2. The OUT pin of the touch chip U6 is electrically connected to the V_CHK2 pin of the main control chip U3. The charging / discharging positive pin BAT+ is electrically connected to the VDD pin of the touch chip U6. One end of each capacitor C1 and capacitor C2 is grounded. The other end of capacitor C2 is connected between the charging / discharging positive pin BAT+ and the VDD pin of the touch chip U6. The other end of capacitor C1 is connected to the touch input terminal of the touch chip U6.

8. The multi-channel WDRC hearing aid circuit according to claim 5, characterized in that: The LED module includes a transistor Q1, resistors R3 and R4, and a light-emitting diode LED2. Resistor R3 is connected between the positive charging / discharging pin BAT+ and the positive terminal of LED2. The negative terminal of LED2 is electrically connected to the collector of transistor Q1. Resistor R4 is connected between the base of transistor Q1 and the GPIO4 pin of the main control chip U3. The emitter of transistor Q1 is grounded.

9. The multi-channel WDRC hearing aid circuit according to claim 5, characterized in that: The main control module also includes a UART serial communication port and a resistor R9. The resistor R9 is connected between the VOUT pin of the voltage regulator chip U4 and the GPIO0 pin of the main control chip U3. The GPIO2 pin of the main control chip U3 and the input terminal of the UART serial communication port are both electrically connected between the resistor R9 and the GPIO0 pin of the main control chip U3.

10. A multi-channel WDRC hearing aid, characterized in that: The hearing aid includes a first outer shell, a hollow tube, and a second outer shell connected in sequence. The hollow tube is bent into a U-shape. The first outer shell contains a circuit board and a lithium battery. The circuit board contains a multi-channel WDRC hearing aid circuit as described in any one of claims 1 to 9. The second outer shell contains a speaker. The hollow tube contains a positive wire and a negative wire. The two ends of the positive wire are electrically connected to the positive terminal of the speaker and the SDMP pin of the main control chip U3, respectively. The two ends of the negative wire are electrically connected to the negative terminal of the speaker and the SDMN pin of the main control chip U3, respectively.

Images