Medical Bluetooth earplug intercom system

Abstract

The utility model provides a medical Bluetooth earplug intercom system, and belongs to the technical field of electronic equipment. The medical Bluetooth earplug intercom system comprises an audio acquisition module, a comparison module, a first switch, a first audio amplification module, an audio output module, a Bluetooth communication module, a second audio amplification module and a signal decoding module. The output end of the audio acquisition module is connected with the first input end of the comparison module. The second input end of the comparison module is used for receiving reference voltage, and the output end is connected with the control end of the first switch. The first end of the first switch is connected with the audio acquisition module, and the second end is connected to the audio output module through the first audio amplification module. The output end of the Bluetooth communication module is connected with the signal decoding module, and the signal decoding module is connected to the audio output module through the second audio amplification module. According to the invention, the ear of a wearer can be protected from being hurt by strong noise, and meanwhile, the wearer can still keep the perception capability of environment sound and carry out normal communication or communication.

Description

Technical Field

[0001] This disclosure relates to the field of electronic equipment technology, and more particularly to a medical Bluetooth earpiece intercom system. Background Technology

[0002] In environments such as blasting sites, shooting ranges, and grenade dropping sites, the instantaneously generated high-intensity noise and shockwaves pose a significant threat to people's ears, easily causing blast-induced hearing loss. Traditional hearing protection devices, such as ordinary earplugs or earmuffs, passively reduce noise through physical blocking. However, wearing traditional earplugs weakens the wearer's ability to perceive sounds in the surrounding environment, severely hindering communication and instruction among wearers. This fails to meet the wearer's practical needs for environmental sound perception and normal communication while protecting their ears from intense noise damage. Utility Model Content

[0003] This disclosure provides a medical Bluetooth earpiece intercom system to ensure that the wearer can maintain the ability to perceive ambient sounds and conduct normal communication while protecting their ears from strong noise damage.

[0004] This disclosure provides a medical Bluetooth earpiece intercom system, including: an audio acquisition module, a comparison module, a first switch, a first audio amplification module, an audio output module, a Bluetooth communication module, a second audio amplification module, and a signal decoding module;

[0005] The audio acquisition module is configured to acquire ambient audio signals. The output terminal of the audio acquisition module is connected to the first input terminal of the comparison module. The second input terminal of the comparison module is used to receive a reference voltage Vref. The output terminal of the comparison module is connected to the control terminal of the first switch. The first terminal of the first switch is connected to the audio acquisition module, and the second terminal of the first switch is connected to the first input terminal of the audio output module through the first audio amplification module.

[0006] The Bluetooth communication module is configured to receive audio signals from the intercom system. The output of the Bluetooth communication module is connected to the input of the signal decoding module. The output of the signal decoding module is connected to the second input of the audio output module through the second audio amplification module.

[0007] The audio output module is configured to output audio signals.

[0008] In one exemplary embodiment of this disclosure, the first audio amplification module includes:

[0009] Preamplifier circuit, peak detection circuit, gain adjustment circuit and threshold detection circuit;

[0010] The preamplifier circuit is connected to the second terminal of the first switch, the peak detection circuit, and the gain adjustment circuit, respectively.

[0011] The threshold detection circuit is connected to the peak detection circuit and the gain adjustment circuit, respectively.

[0012] The gain adjustment circuit is connected to the first input terminal of the audio output module.

[0013] In one exemplary embodiment of this disclosure, the preamplifier circuit includes:

[0014] Non-inverting amplifier circuit;

[0015] The in-phase amplifier circuit is connected to the second terminal of the first switch, the peak detection circuit, and the gain adjustment circuit, respectively.

[0016] In one exemplary embodiment of this disclosure, the preamplifier circuit includes:

[0017] Bandpass filter circuit;

[0018] The bandpass filter circuit is connected to the second terminal of the first switch and the in-phase amplifier circuit, respectively.

[0019] The in-phase amplifier circuit is connected to the peak detection circuit and the gain adjustment circuit, respectively.

[0020] In one exemplary embodiment of this disclosure, the peak detection circuit includes:

[0021] Diode D1, resistor R6, capacitor C3, and operational amplifier U1B;

[0022] The first terminal of diode D1 is connected to the preamplifier circuit, and the second terminal of diode D1 is connected to the first terminal of resistor R6 and the first terminal of capacitor C3 respectively. The second terminal of resistor R6 is used for grounding, and the second terminal of capacitor C3 is connected to the second terminal of resistor R6.

[0023] The second end of the resistor R6 is connected to the non-inverting input of the operational amplifier U1B, the inverting input of the operational amplifier U1B is connected to the output of the operational amplifier U1B, and the output of the operational amplifier U1B is connected to the threshold detection circuit.

[0024] In one exemplary embodiment of this disclosure, the threshold detection circuit includes:

[0025] Comparator U2A and comparator U2B;

[0026] The non-inverting input of comparator U2A and the non-inverting input of comparator U2B are both connected to the peak detection circuit.

[0027] The inverting input of comparator U2A is used to receive the reference voltage REF2, and the inverting input of comparator U2B is used to receive the reference voltage REF1.

[0028] The output terminals of comparator U2A and comparator U2B are respectively connected to the two control terminals of the gain adjustment circuit.

[0029] In one exemplary embodiment of this disclosure, the gain adjustment circuit includes:

[0030] Resistors R8, R9, R10, multiplex analog switch, operational amplifier U3A and operational amplifier U3B;

[0031] The first terminals of resistors R8, R9, and R10 are all connected to the preamplifier circuit.

[0032] The second end of resistor R8 is connected to the first end of the multiplex analog switch, the second end of resistor R9 is connected to the second end of the multiplex analog switch, and the second end of resistor R10 is connected to the third end of the multiplex analog switch.

[0033] The first control terminal of the multiplexer is connected to the output terminal of the comparator U2A, and the second control terminal of the multiplexer is connected to the output terminal of the comparator U2B.

[0034] The output terminal of the multi-channel analog switch is connected to the inverting input terminal of the operational amplifier U3A;

[0035] The non-inverting input terminal of the operational amplifier U3A is grounded, and the output terminal of the operational amplifier U3A is fed back to the inverting input terminal of the operational amplifier U3A through resistor R11.

[0036] The output terminal of operational amplifier U3A is connected to the inverting input terminal of operational amplifier U3B. The non-inverting input terminal of operational amplifier U3B is grounded. The output terminal of operational amplifier U3B is fed back to the inverting input terminal of operational amplifier U3B through resistor R15. The output terminal of operational amplifier U3B is the output terminal of the gain adjustment circuit.

[0037] In one exemplary embodiment of this disclosure, a medical Bluetooth earpiece intercom system further includes:

[0038] Indicator light module;

[0039] The indicator module is connected to the comparison module; the indicator module is configured to indicate the on / off state of the first switch.

[0040] The beneficial effects of the medical Bluetooth earpiece intercom system provided in this disclosure are as follows:

[0041] On the one hand, considering that wearing earplugs with strong sound insulation will reduce the user's ability to perceive ambient sounds, this embodiment of the present disclosure integrates an audio acquisition module to effectively capture ambient sounds and transmit them to the wearer; at the same time, this embodiment of the present disclosure also uses a Bluetooth communication module to realize a clear voice intercom function, thereby ensuring that the wearer can still maintain the ability to perceive ambient sounds and communicate normally while protecting their ears from damage, thus improving safety and meeting the user's actual needs.

[0042] On the other hand, by using the comparison module in conjunction with the first switch, when the collected audio signal is higher than the safety threshold, the comparison module controls the first switch to open, effectively isolating noise exceeding the safety threshold and avoiding occupational injuries such as blast-induced hearing loss, thus providing reliable hearing protection for the wearer; when the collected audio signal is lower than the safety threshold, the comparison module controls the first switch to close, enabling real-time acquisition and processing of environmental audio signals to meet the user's needs for environmental sound perception. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a schematic diagram of the structure of a medical Bluetooth earpiece intercom system provided in an embodiment of this disclosure;

[0045] Figure 2 This is a schematic diagram of the structure of the first audio amplification module provided in an embodiment of this disclosure;

[0046] Figure 3 This is the circuit of the first audio amplification module provided in the embodiments of this disclosure. Detailed Implementation

[0047] To enable those skilled in the art to better understand this solution, the technical solutions in the embodiments of this solution will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this solution, not all of them. Based on the embodiments of this solution, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this solution.

[0048] The term "comprising" and any other variations thereof in the specification, claims, and accompanying drawings of this invention mean "including but not limited to," and are intended to cover a non-exclusive inclusion, not limited to the examples listed herein. Furthermore, the terms "first" and "second," etc., are used to distinguish different objects, not to describe a specific order.

[0049] The implementation of this disclosure will be described in detail below with reference to the specific accompanying drawings:

[0050] Figure 1 This is a schematic diagram of a medical Bluetooth earpiece intercom system provided in an embodiment of this disclosure. (Refer to...) Figure 1 The medical Bluetooth earpiece intercom system includes: an audio acquisition module, a comparison module, a first switch, a first audio amplification module, an audio output module, a Bluetooth communication module, a second audio amplification module, and a signal decoding module.

[0051] The audio acquisition module is configured to acquire ambient audio signals. The output terminal of the audio acquisition module is connected to the first input terminal of the comparison module. The second input terminal of the comparison module is used to receive a reference voltage Vref. The output terminal of the comparison module is connected to the control terminal of the first switch. The first terminal of the first switch is connected to the audio acquisition module, and the second terminal of the first switch is connected to the first input terminal of the audio output module through the first audio amplification module.

[0052] The Bluetooth communication module is configured to receive audio signals from the intercom system. The output of the Bluetooth communication module is connected to the input of the signal decoding module. The output of the signal decoding module is connected to the second input of the audio output module through the second audio amplification module.

[0053] The audio output module is configured to output audio signals.

[0054] In this embodiment, the audio acquisition module may include a microphone positioned on the outside of the earpiece, near the entrance to the ear canal, with its surface covered by a waterproof and dustproof filter. For example, the audio acquisition module may employ a high-sensitivity MEMS microphone array, using multi-microphone beamforming technology to directionally acquire ambient sound waves and suppress lateral noise interference. The dynamic range covers 20-140dB, ensuring complete capture from whispers to gunshots.

[0055] The comparison module may include a comparator that compares the audio signal output from the audio acquisition module with a reference voltage Vref. Based on the comparison result, the comparator outputs a control signal to control the switching state of the first switch. For example, the comparator's reference voltage Vref represents the safe intensity threshold of ambient audio and is generated by a digital-to-analog converter. For instance, the reference voltage Vref could be an equivalent electrical signal of a 140dB sound pressure level. When the comparator's input signal exceeds Vref, the comparator outputs a high level to drive the first switch open, ensuring that the audio transmission path is cut off before a strong audio shock wave arrives. When the comparator's input signal does not exceed Vref, the comparator outputs a low level to keep the first switch closed, opening the audio transmission path so that the wearer can clearly perceive ambient sounds.

[0056] The first switch can be a transistor or a relay, etc. When the first switch is closed, the audio acquisition module transmits the acquired ambient audio to the first audio amplification module for audio signal processing, and then the audio output module plays it to the earphone wearer. When the first switch is open, the transmission channel of the ambient audio is disconnected, isolating external sounds.

[0057] The first and second audio amplification modules have the same circuit structure, but they process audio signals from different sources. The audio output module may include a speaker that converts the processed audio signal into sound and plays it to the wearer. The Bluetooth communication module is configured to enable wireless communication between the earbuds and other Bluetooth devices, transmitting voice signals. The signal decoding module may include a decoder that decodes the encoded digital audio signal received by the Bluetooth communication module to restore the original audio signal.

[0058] For example, the microphone of the audio acquisition module collects sound signals from the surrounding environment and outputs them to the comparison module. The comparison module compares the audio signal output by the audio acquisition module with a reference voltage Vref, and outputs a control signal to a first switch based on the comparison result. The first switch controls the connection between the audio acquisition module and the first audio amplification module according to the control signal output by the comparison module. When the audio signal is higher than a safety threshold, the switch is open. When the audio signal is lower than the safety threshold, the switch is closed.

[0059] When the first switch is closed, the ambient audio signal acquired by the audio acquisition module is transmitted to the first audio amplification module for amplification. The Bluetooth communication module establishes a connection with other Bluetooth devices to achieve wireless transmission of voice signals. The audio signal received by the Bluetooth communication module is transmitted to the signal decoding module, which decodes the received encoded audio signal, restores the original audio signal, and transmits it to the second audio amplification module for amplification. The amplified audio signal is then transmitted to the audio output module and played back to the wearer through a speaker.

[0060] On the one hand, when users wear earplugs with strong sound insulation, their ability to perceive ambient sounds is reduced. This embodiment, by integrating an advanced audio acquisition and processing module, can effectively capture and amplify ambient sounds and transmit them to the wearer. Simultaneously, this embodiment also utilizes a Bluetooth communication module to achieve clear voice communication, thereby ensuring that the wearer can maintain their ability to perceive ambient sounds and communicate normally while protecting their ears from harm, improving safety and meeting the user's actual needs.

[0061] On the other hand, by using the comparison module in conjunction with the first switch, high-intensity noise can be identified and the audio processing and transmission path can be cut off. When the acquired audio signal is higher than the safety threshold, the comparison module controls the first switch to open, effectively isolating noise exceeding the safety threshold and avoiding occupational injuries such as blast-induced hearing loss, thus providing reliable hearing protection for the wearer. When the acquired audio signal is lower than the safety threshold, the comparison module controls the first switch to close, allowing for real-time acquisition and processing of environmental audio signals to meet the user's needs for environmental sound perception.

[0062] like Figure 2 As shown, in one embodiment of this disclosure, the first audio amplification module includes:

[0063] The circuit includes a preamplifier circuit, a peak detection circuit, a gain adjustment circuit, and a threshold detection circuit.

[0064] The preamplifier circuit is connected to the second terminal of the first switch, the peak detection circuit, and the gain adjustment circuit, respectively.

[0065] The threshold detection circuit is connected to both the peak detection circuit and the gain adjustment circuit.

[0066] The gain adjustment circuit is connected to the first input terminal of the audio output module.

[0067] In this embodiment, the preamplifier circuit includes:

[0068] Non-inverting amplifier circuit.

[0069] The in-phase amplifier circuit is connected to the second terminal of the first switch, the peak detection circuit, and the gain adjustment circuit, respectively.

[0070] In this embodiment, the preamplifier circuit includes:

[0071] Bandpass filter circuit.

[0072] The bandpass filter circuit is connected to the second terminal of the first switch and the in-phase amplifier circuit, respectively.

[0073] The in-phase amplifier circuit is connected to the peak detection circuit and the gain adjustment circuit, respectively.

[0074] like Figure 3 As shown, in this embodiment, the non-inverting amplifier circuit includes an operational amplifier U1A, a resistor R4, and a resistor R5, and the bandpass filter circuit includes a resistor R1, a capacitor C1, a capacitor C2, and a resistor R2.

[0075] The first end of resistor R1 is connected to the second end of the first switch, and the second end of resistor R1 is connected to the first end of capacitor C1 and the first end of capacitor C2 respectively.

[0076] The second terminal of capacitor C1 is connected to the first terminal of resistor R2, and the second terminal of capacitor C2 is connected to the second terminal of resistor R2. The first terminal of resistor R2 is used for grounding.

[0077] The second end of resistor R2 is connected to the non-inverting input of op-amp U1A. The inverting input of op-amp U1A is grounded through resistor R4. The inverting input of op-amp U1A is connected to the output of op-amp U1A through resistor R5.

[0078] In this embodiment, the preamplifier circuit can initially amplify the input audio signal. The bandpass filter circuit filters out audio signals within a specific frequency range, removing unnecessary interference signals. The in-phase amplifier circuit amplifies the filtered signal, enhancing its strength. The peak detection circuit is configured to detect the peak value of the preamplifier circuit's output signal. By monitoring the peak value, the intensity changes of the audio signal can be understood, providing a basis for subsequent gain adjustment.

[0079] For example, the audio signal is input from the second terminal of the first switch and first passes through a bandpass filter circuit. Resistor R1, capacitor C1, and capacitor C2 form a frequency selection network, allowing signals within a specific frequency range to pass through, while signals of other frequencies are attenuated. The filtered signal enters the non-inverting amplifier circuit, where operational amplifier U1A operates in non-inverting mode. The ratio of resistors R4 and R5 determines the amplification factor, thus amplifying the output signal proportionally.

[0080] In this embodiment, the gain adjustment circuit is configured to dynamically adjust the amplification factor of the audio signal based on the output of the threshold detection circuit. When the audio signal intensity changes, adjusting the gain through the gain adjustment circuit can stabilize the signal intensity output to the audio output module within a suitable range. The threshold detection circuit is configured to compare the signal output by the peak detection circuit with a preset threshold, and output a control signal to the gain adjustment circuit based on the comparison result.

[0081] For example, the threshold detection circuit compares the input peak signal with a reference voltage. When the peak signal is higher than the reference voltage, it outputs a high level. When the peak signal is lower than the reference voltage, it outputs a low level. These high and low level signals serve as control signals to control the gain adjustment circuit to adjust the gain.

[0082] For example, when staff wear the medical Bluetooth earpiece intercom system of this embodiment, the audio signal strength is low under normal conditions. The preamplifier circuit filters and amplifies the collected ambient sounds, enabling the signal to be processed by subsequent circuits. The peak detection circuit detects the peak value of the signal, the threshold detection circuit determines that the signal is below a preset threshold, and the gain adjustment circuit increases the amplification factor, allowing staff to clearly hear ambient sounds, such as light footsteps and equipment operation sounds, facilitating their perception of the environment.

[0083] In this embodiment, the preamplifier circuit's bandpass filtering and in-phase proportional amplification can filter signals and enhance their intensity, thereby improving audio quality. Peak detection, threshold detection, and gain adjustment circuits work together to dynamically adjust the amplification factor based on audio intensity. Under normal conditions, this allows staff to clearly perceive ambient sounds, meeting communication and environmental awareness needs while effectively isolating loud external noise and protecting hearing.

[0084] like Figure 3 As shown, in one embodiment of this disclosure, the peak detection circuit includes:

[0085] Diode D1, resistor R6, capacitor C3, and operational amplifier U1B.

[0086] The first terminal of diode D1 is connected to the preamplifier circuit. The second terminal of diode D1 is connected to the first terminal of resistor R6 and the first terminal of capacitor C3. The second terminal of resistor R6 is used for grounding, and the second terminal of capacitor C3 is connected to the second terminal of resistor R6.

[0087] The second end of resistor R6 is connected to the non-inverting input of op-amp U1B, the inverting input of op-amp U1B is connected to the output of op-amp U1B, and the output of op-amp U1B is connected to the threshold detection circuit.

[0088] In this embodiment, the peak detection circuit can detect the peak value of the audio signal output by the preamplifier circuit, convert the peak signal into a relatively stable voltage value and output it to the threshold detection circuit, so that the gain can be adjusted according to the signal peak intensity, thereby ensuring that the audio signal output is within a suitable range, protecting the user's hearing and providing a clear audio experience.

[0089] For example, when an audio signal is output from the preamplifier circuit and input to the peak detection circuit, the signal first passes through diode D1. If the input signal voltage is higher than the voltage on capacitor C3, diode D1 conducts, and current flows through diode D1 to charge capacitor C3. The voltage on capacitor C3 gradually increases until it approaches the peak value of the input signal.

[0090] When the input signal voltage is lower than the voltage across capacitor C3, diode D1 is cut off, and capacitor C3 slowly discharges through resistor R6. Due to the presence of resistor R6, capacitor C3 discharges slowly, maintaining a voltage close to the signal peak for a certain period of time.

[0091] The voltage across capacitor C3 is connected to the non-inverting input of operational amplifier U1B, and the inverting input of operational amplifier U1B is connected to its output, forming a voltage follower structure. The voltage follower features high input impedance and low output impedance, enabling it to output the voltage across capacitor C3 to the threshold detection circuit without attenuation, ensuring accurate transmission of the peak signal.

[0092] The peak detection circuit in this embodiment can accurately detect the peak value of the audio signal output by the preamplifier circuit and convert it into a stable voltage output to the threshold detection circuit. When the audio signal intensity changes, subsequent gain adjustment can ensure that the audio output is within a suitable range, enhancing the user experience.

[0093] like Figure 3 As shown, in one embodiment of this disclosure, the threshold detection circuit includes:

[0094] Comparator U2A and comparator U2B.

[0095] The non-inverting input of comparator U2A and the non-inverting input of comparator U2B are both connected to the peak detection circuit.

[0096] The inverting input of comparator U2A is used to receive the reference voltage REF2, and the inverting input of comparator U2B is used to receive the reference voltage REF1.

[0097] The output terminals of comparator U2A and comparator U2B are respectively connected to the two control terminals of the gain adjustment circuit.

[0098] In this embodiment, the threshold detection circuit can compare the signal output by the peak detection circuit with a preset reference voltage, and output a control signal to the gain adjustment circuit based on the comparison result, thereby realizing dynamic adjustment of the audio signal gain.

[0099] In this embodiment, the non-inverting inputs of comparators U2A and U2B are both connected to a peak detection circuit to receive the peak signal. The inverting input of comparator U2A receives a reference voltage REF2, and the inverting input of comparator U2B receives a reference voltage REF1. When the peak signal is higher than REF2, both comparators U2A and U2B output a high level. When the peak signal is lower than REF2 but higher than REF1, comparator U2A outputs a low level, and comparator U2B outputs a high level. When the peak signal is lower than REF1, both comparators U2B and U2A output a low level. These high and low level signals serve as control signals, which are passed to the gain adjustment circuit to adjust the amplification factor of the audio signal.

[0100] For example, when the signal output by the peak detection circuit is weak, below REF1, the comparator U2B outputs a low level, and the gain adjustment circuit increases the amplification factor, allowing the wearer to clearly hear faint ambient sounds and the other person's quiet conversation. However, in a noisy environment, the peak signal is higher than REF2, the comparator U2A outputs a high level, and the gain adjustment circuit reduces the amplification factor, preventing damage to the ears from strong noise.

[0101] The threshold detection circuit in this embodiment can accurately output control signals based on the different audio signal strengths, enabling the gain adjustment circuit to dynamically adjust the audio amplification factor. This ensures clear sound perception in quiet environments while effectively protecting the user's hearing in noisy environments, thus improving the practicality and safety of the medical Bluetooth earpiece intercom system.

[0102] like Figure 3 As shown, in one embodiment of this disclosure, the gain adjustment circuit includes:

[0103] Resistors R8, R9, R10, multiplex analog switch, op-amp U3A and op-amp U3B.

[0104] The first terminals of resistors R8, R9, and R10 are all connected to the preamplifier circuit.

[0105] The second terminal of resistor R8 is connected to the first terminal of the multiplexer, the second terminal of resistor R9 is connected to the second terminal of the multiplexer, and the second terminal of resistor R10 is connected to the third terminal of the multiplexer.

[0106] The first control terminal of the multiplexer is connected to the output terminal of the comparator U2A, and the second control terminal of the multiplexer is connected to the output terminal of the comparator U2B.

[0107] The output terminal of the multi-channel analog switch is connected to the inverting input terminal of the operational amplifier U3A;

[0108] The non-inverting input terminal of the operational amplifier U3A is grounded, and the output terminal of the operational amplifier U3A is fed back to the inverting input terminal of the operational amplifier U3A through resistor R11.

[0109] The output terminal of operational amplifier U3A is connected to the inverting input terminal of operational amplifier U3B. The non-inverting input terminal of operational amplifier U3B is grounded. The output terminal of operational amplifier U3B is fed back to the inverting input terminal of operational amplifier U3B through resistor R15. The output terminal of operational amplifier U3B is the output terminal of the gain adjustment circuit.

[0110] In this embodiment, the gain adjustment circuit is configured to dynamically adjust the amplification factor of the audio signal based on the control signal output by the threshold detection circuit, ensuring that the signal strength output to the audio output module remains stable within a safe and clear range. By selecting different resistor networks, multi-level gain switching can be achieved, balancing signal enhancement in low-noise environments and signal attenuation in high-noise environments.

[0111] In this embodiment, one end of resistors R8, R9, and R10 is connected to the output of the preamplifier circuit, and the other end is connected to different channels (first, second, and third terminals) of the multiplexer analog switch, respectively. The first and second control terminals of the multiplexer analog switch receive control signals (outputs of U2A and U2B) from the threshold detection circuit, and select different resistor paths based on the combination of high and low input levels. For example:

[0112] When U2A outputs a high level (signal exceeds REF2), select R8 (low gain path).

[0113] When U2A outputs a low level and U2B outputs a high level (the signal is between REF1 and REF2), select R9 (medium gain path).

[0114] When the U2B output is low (signal is below REF1), select R10 (high gain path).

[0115] The output signal from the multiplexer analog switch enters the inverting input of the operational amplifier U3A, while its non-inverting input is grounded. The output is fed back to the inverting input through resistor R5, forming an inverting proportional amplifier circuit. The amplification factor of the inverting proportional amplifier circuit is determined by the selector resistor of the multiplexer analog switch.

[0116] The output signal of op-amp U3A is input to the inverting input terminal of op-amp U3B. Op-amp U3B forms the second stage of the inverting proportional amplifier circuit, which transmits the output signal of op-amp U3A to the speaker without distortion, avoiding the load effect from affecting the accuracy of gain adjustment.

[0117] For example, consider a medical Bluetooth earpiece intercom system used at a blasting site:

[0118] Low-volume scenario: When the ambient sound is weak, the peak detection circuit output voltage is lower than REF1, U2B outputs a low level, and the multi-channel analog switch selects R10 (high-gain path). At this time, the weak signal output by the preamplifier circuit is amplified by a high factor through R10, allowing the wearer to clearly hear the device prompts or the whispered instructions of a companion.

[0119] In a medium volume scenario: the audio signal is between REF1 and REF2, the U2B output is high, and the analog multi-channel switch is switched to R9 (medium gain path). At this time, maintain moderate amplification to ensure that ambient sounds are distinguishable without being harsh.

[0120] High-volume scenarios: When the peak signal exceeds REF2, U2A outputs a high level, and the multi-channel analog switch selects R8 (low-gain path). At this time, strong noise signals are significantly attenuated to prevent sound waves exceeding the safety threshold from damaging the eardrum, while retaining necessary communication signals.

[0121] Among them, Vref is greater than REF2, and REF2 is greater than REF1.

[0122] This embodiment utilizes a three-stage resistor network and multiple analog switches to achieve multi-level gain adjustment, adapting to a full range of noise environments from low to high, balancing clarity and safety. Combined with a threshold detection circuit and dual-threshold comparison, it ensures the smoothness and stability of gain adjustment. It automatically reduces gain under strong noise conditions to effectively protect hearing. In quiet environments, it increases gain to ensure voice communication and environmental awareness. In summary, this gain adjustment circuit, through its hardware-level fast response and multi-level selection, significantly improves the adaptability of medical Bluetooth earbuds in complex noise environments, providing users with reliable hearing protection and a clear auditory experience.

[0123] In one embodiment of this disclosure, a medical Bluetooth earpiece intercom system further includes:

[0124] Indicator light module.

[0125] The indicator module is connected to the comparator module. The indicator module is configured to indicate the on / off state of the first switch.

[0126] In this embodiment, the indicator module may include LED indicator lights, which are located on the outside of the earbud or on the stem, for visually displaying the status (such as red, green, or yellow LEDs). The LED indicator lights can provide real-time feedback on the on / off status of the first switch through light color or flashing pattern, indicating whether the medical Bluetooth earbud intercom system is in "ambient sound transmission" or "strong noise isolation" mode. This helps the wearer quickly determine whether the system is working properly or whether intervention is needed.

[0127] For example, when a high-intensity blasting sound wave is detected, the comparison module triggers the first switch to open, and the red LED lights up to indicate to the user that "hearing protection mode has been entered." After the blasting sound wave ends and the ambient sound returns to normal, the first switch closes, the green LED lights up, and the user can perceive the environment again.

[0128] This embodiment provides visual feedback, allowing users to confirm whether the medical Bluetooth earpiece intercom system is in a protected state without relying on hearing, especially avoiding misjudgment during sudden loud noise. If the indicator light flashes abnormally or does not illuminate, it may indicate a fault in the comparison module or circuitry, facilitating timely repair. The LED consumes extremely low power, having a negligible impact on the earpiece's overall battery life, making it suitable for extended use.

[0129] The above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit it. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A medical Bluetooth earpiece intercom system, characterized in that, include: The system includes an audio acquisition module, a comparison module, a first switch, a first audio amplification module, an audio output module, a Bluetooth communication module, a second audio amplification module, and a signal decoding module. The audio acquisition module is configured to acquire ambient audio signals. The output terminal of the audio acquisition module is connected to the first input terminal of the comparison module. The second input terminal of the comparison module is used to receive a reference voltage Vref. The output terminal of the comparison module is connected to the control terminal of the first switch. The first terminal of the first switch is connected to the audio acquisition module, and the second terminal of the first switch is connected to the first input terminal of the audio output module through the first audio amplification module. The Bluetooth communication module is configured to receive audio signals from the intercom system. The output of the Bluetooth communication module is connected to the input of the signal decoding module. The output of the signal decoding module is connected to the second input of the audio output module through the second audio amplification module. The audio output module is configured to output audio signals.

2. The medical Bluetooth earpiece intercom system as described in claim 1, characterized in that, The first audio amplification module includes: Preamplifier circuit, peak detection circuit, gain adjustment circuit and threshold detection circuit; The preamplifier circuit is connected to the second terminal of the first switch, the peak detection circuit, and the gain adjustment circuit, respectively. The threshold detection circuit is connected to the peak detection circuit and the gain adjustment circuit, respectively. The gain adjustment circuit is connected to the first input terminal of the audio output module.

3. A medical Bluetooth earpiece intercom system as described in claim 2, characterized in that, The preamplifier circuit includes: Non-inverting amplifier circuit; The in-phase amplifier circuit is connected to the second terminal of the first switch, the peak detection circuit, and the gain adjustment circuit, respectively.

4. A medical Bluetooth earpiece intercom system as described in claim 3, characterized in that, The preamplifier circuit includes: Bandpass filter circuit; The bandpass filter circuit is connected to the second terminal of the first switch and the in-phase amplifier circuit, respectively. The in-phase amplifier circuit is connected to the peak detection circuit and the gain adjustment circuit, respectively.

5. A medical Bluetooth earpiece intercom system as described in claim 2, characterized in that, The peak detection circuit includes: Diode D1, resistor R6, capacitor C3, and operational amplifier U1B; The first terminal of diode D1 is connected to the preamplifier circuit, and the second terminal of diode D1 is connected to the first terminal of resistor R6 and the first terminal of capacitor C3 respectively. The second terminal of resistor R6 is used for grounding, and the second terminal of capacitor C3 is connected to the second terminal of resistor R6. The second end of the resistor R6 is connected to the non-inverting input of the operational amplifier U1B, the inverting input of the operational amplifier U1B is connected to the output of the operational amplifier U1B, and the output of the operational amplifier U1B is connected to the threshold detection circuit.

6. A medical Bluetooth earpiece intercom system as described in claim 2, characterized in that, The threshold detection circuit includes: Comparator U2A and comparator U2B; The non-inverting input of comparator U2A and the non-inverting input of comparator U2B are both connected to the peak detection circuit. The inverting input of comparator U2A is used to receive the reference voltage REF2, and the inverting input of comparator U2B is used to receive the reference voltage REF1. The output terminals of comparator U2A and comparator U2B are respectively connected to the two control terminals of the gain adjustment circuit.

7. A medical Bluetooth earpiece intercom system as described in claim 6, characterized in that, The gain adjustment circuit includes: Resistors R8, R9, R10, multiplex analog switch, operational amplifier U3A and operational amplifier U3B; The first terminals of resistors R8, R9, and R10 are all connected to the preamplifier circuit. The second end of resistor R8 is connected to the first end of the multiplex analog switch, the second end of resistor R9 is connected to the second end of the multiplex analog switch, and the second end of resistor R10 is connected to the third end of the multiplex analog switch. The first control terminal of the multiplexer is connected to the output terminal of the comparator U2A, and the second control terminal of the multiplexer is connected to the output terminal of the comparator U2B. The output terminal of the multi-channel analog switch is connected to the inverting input terminal of the operational amplifier U3A; The non-inverting input terminal of the operational amplifier U3A is grounded, and the output terminal of the operational amplifier U3A is fed back to the inverting input terminal of the operational amplifier U3A through resistor R11. The output terminal of operational amplifier U3A is connected to the inverting input terminal of operational amplifier U3B. The non-inverting input terminal of operational amplifier U3B is grounded. The output terminal of operational amplifier U3B is fed back to the inverting input terminal of operational amplifier U3B through resistor R15. The output terminal of operational amplifier U3B is the output terminal of the gain adjustment circuit.

8. A medical Bluetooth earpiece intercom system as described in claim 1, characterized in that, Also includes: Indicator light module; The indicator module is connected to the comparison module; the indicator module is configured to indicate the on / off state of the first switch.

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