Infrared transmitting and receiving circuit

Abstract

The utility model belongs to the technical field of infrared, and relates to an infrared transmitting and receiving circuit which comprises an infrared transmitting module, an infrared receiving module, a current-limiting resistor R0 and a filter capacitor C1 which are electrically connected, and the infrared receiving module is provided with a power supply control module, a CMOS image sensor, a photodiode, an ADC, an LED driving module, an I2C communication module and a digital processing unit DSP. The infrared transmitting module is used for transmitting an infrared signal, the infrared receiving module is used for receiving and decoding the infrared signal to realize a remote control or data transmission function, and the current-limiting resistor is used for limiting the magnitude of current and preventing components from being damaged. The device is simple in structure, low in cost, high in anti-interference capability, wide in sensing range and high in sensitivity, and can be freely adjusted according to the brightness of ambient light; the sensing device can be widely applied to intelligent multifunctional sensing faucets, sensing sanitary appliances, sensing hand dryer garbage cans, soap dispensers, air dryers, urinals and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of infrared, and more specifically, to an infrared transmitting and receiving circuit. Background Art

[0002] An infrared transmitting and receiving circuit refers to a circuit system that uses infrared rays as a communication medium to achieve information transmission and reception. This system mainly consists of two core parts: an infrared transmitter and an infrared receiver, which together form the basis of infrared communication.

[0003] The main function of the infrared transmitting and receiving circuit is to achieve wireless communication between devices. The infrared transmitter emits infrared light signals at a specific frequency, and these signals carry the information to be transmitted. The infrared receiver is responsible for receiving these infrared light signals, converting them into electrical signals, and then performing decoding processing. In this way, the infrared transmitting and receiving circuit can achieve information transmission between devices without physical connection.

[0004] The application scenarios of the infrared transmitting and receiving circuit are very extensive. First of all, in the field of remote controls, the infrared transmitting and receiving circuit is indispensable. The TV remote controls, air conditioner remote controls, etc. that we use daily all adopt infrared communication technology. Users can generate corresponding infrared signals by pressing the buttons on the remote control, and then control the operations of devices such as TVs and air conditioners. Secondly, in the automated control system, the infrared transmitting and receiving circuit also plays an important role. For example, in a vehicle speed measurement system, an infrared sensor can accurately measure the vehicle speed by sending and receiving infrared signals. In addition, the infrared transmitting and receiving circuit is also widely used in anti-theft devices, infrared switches and other fields.

[0005] The existing infrared transmitting and receiving circuit has a complex structure, high cost, and weak anti-interference ability. Summary of the Utility Model

[0006] In view of the above defects of the prior art, the utility model provides an infrared transmitting and receiving circuit, including:

[0007] An infrared emission module, an infrared reception module, a current-limiting resistor R0, and a filtering capacitor C1 are electrically connected. The infrared reception module is provided with a power control module, a CMOS image sensor, a photodiode, an ADC, an LED driving module, an I2C communication module, and a digital processing unit DSP. The infrared emission module is used to emit infrared signals. The infrared reception module receives and decodes the infrared signals to implement remote control or data transmission functions. The current-limiting resistor is used to limit the magnitude of the current to prevent component damage. The filtering capacitor is used to filter out clutter interference and improve the signal quality. The photodiode is used to receive the infrared signals and convert them into electrical signals. The I2C communication module is used to transmit the data collected by the CMOS image sensor and the photodiode to the digital processing unit DSP, and is also used to send the control instructions received from the digital processing unit DSP to the LED driving module.

[0008] Preferably, the infrared emission module includes an infrared light-emitting diode and a driving circuit.

[0009] Preferably, the infrared reception module further includes a preamplifier, a filtering circuit, a demodulation circuit, and an output circuit. The preamplifier is used to amplify the electrical signals. The filtering circuit is used to filter out clutter interference. The demodulation circuit is used to restore the modulated signals to the original signals. The output circuit then outputs the demodulated signals to the controller for processing.

[0010] Preferably, the power control module includes a power detection circuit, a voltage regulation circuit, and a current protection circuit.

[0011] Preferably, the LED driving module includes: an LED driver, a current limiter, a temperature detection circuit, and a protection circuit.

[0012] Preferably, the filtering circuit includes: a capacitor C1 and a resistor R1 connected in series.

[0013] Preferably, the demodulation circuit includes: a transistor M1, a resistor R2, and a capacitor C2 connected in series.

[0014] Preferably, the power detection circuit includes: a voltage detection circuit and a first comparison circuit.

[0015] Preferably, the voltage regulation circuit includes: a reference voltage source, an error amplifier, and a power adjustment transistor.

[0016] Preferably, the current protection circuit includes: a current detection circuit and a second comparison circuit.

[0017] Implementing the infrared transmission and reception circuit of the present utility model has the following beneficial effects: By providing an infrared emission module, an infrared reception module, a current-limiting resistor R0, and a filtering capacitor C1 that are electrically connected, the infrared reception module is provided with a power control module, a CMOS image sensor, a photodiode, an ADC, an LED driving module, an I2C communication module, and a digital processing unit DSP; it has a simple structure, low cost, strong anti-interference ability, can be freely adjusted according to the brightness of the ambient light, and has a wide sensing range and high sensitivity; it can be widely applied to intelligent multi-functional induction faucets, induction sanitary wares, induction hand dryers, trash cans, soap dispensers, air dryers, urinals, and can be extended to applications in medical treatment, street lamps, corridors, balconies, kitchens, bathrooms, warehouses, elevator entrances, children's rooms, hotel corridors, and utility rooms, etc., where automatic opening and closing are required. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following-described drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings. The present utility model will be further described below in conjunction with the drawings and embodiments. In the drawings:

[0019] Figure 1 is a schematic diagram of the composition of the infrared transmission and reception circuit of the present utility model;

[0020] Figure 2 is a schematic diagram of the light-transmitting and light-blocking safety distance of the CMOS image sensor in the infrared transmission and reception circuit of the present utility model;

[0021] Figure 3 is a schematic diagram of the connection of the infrared emission module in the infrared transmission and reception circuit of the present utility model;

[0022] Figure 4 is a schematic diagram of the connection of the infrared reception module in the infrared transmission and reception circuit of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0024] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present utility model, then such directional indications are only used to explain the relative positional relationship, movement conditions, etc. between components in a certain specific posture (as shown in the drawings). If this specific posture changes, then the directional indications will also change accordingly.

[0025] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present utility model, then such descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present utility model.

[0026] Please refer to Figure 1 , which is a schematic diagram of the composition of the infrared transmission and reception circuit of the present utility model. As Figure 1 shown, in the infrared transmission and reception circuit provided in the first embodiment of the present utility model, it at least includes an infrared emission module, an infrared reception module, a current-limiting resistor R0, and a filter capacitor C1 that are electrically connected. The infrared reception module is provided with a power control module, a CMOS image sensor, a photodiode, an ADC, an LED driving module, an I2C communication module, and a digital processing unit DSP. The infrared emission module is used to emit infrared signals, and the infrared reception module receives and decodes the infrared signals to achieve remote control or data transmission functions. The current-limiting resistor is used to limit the current magnitude to prevent component damage; the filter capacitor is used to filter out clutter interference and improve the signal quality. The photodiode is used to receive infrared signals and convert them into electrical signals. The I2C communication module is used to transmit the data collected by the CMOS image sensor and the photodiode to the digital processing unit DSP, and is also used to send the control instructions received from the digital processing unit DSP to the LED driving module.

[0027] Specifically, when implemented, the current-limiting resistor R0 is connected in series in the circuit of the infrared emission module to limit the current magnitude of the infrared light-emitting diode and prevent it from being damaged due to excessive current. The resistance value of the current-limiting resistor R0 can be calculated according to the rated current of the infrared light-emitting diode and the power supply voltage.

[0028] The filtering capacitor C1 is a component used to filter out the clutter interference in the circuit. In the infrared transmitting and receiving circuit, the filtering capacitor C1 is connected in parallel to the output terminal of the power supply circuit to reduce the AC pulsation ripple coefficient of the power supply circuit output and improve the smoothness of the DC output. The capacitance of the filtering capacitor C1 is selected according to the output current of the power supply circuit and the load resistance.

[0029] The CMOS image sensor is a device used to convert optical signals into electrical signals. In the infrared receiving module, the CMOS image sensor can be used to capture infrared optical signals and convert them into digital signals. The CMOS image sensor has characteristics such as high sensitivity, low power consumption, and fast response.

[0030] Figure 2 It is a schematic diagram of the light-transmitting and light-blocking safety distance of the CMOS image sensor in the infrared transmitting and receiving circuit of the present utility model. As Figure 2 shown, in the light-transmitting and light-blocking safety distance of the CMOS image sensor, d1 is the safety interval between the infrared emitting chip and the infrared receiving chip, which can be 3mm - 7mm, preferably 5mm in this embodiment, d2 is the width of the sensor, which can be 4mm - 8mm, preferably 6mm, and d3 is the length of the CMOS image sensor, which can be 7mm - 11mm, preferably 9mm.

[0031] The photodiode is one of the core components in the infrared receiving module, used to receive infrared optical signals and convert them into weak electrical signals. The photodiode has characteristics such as fast response speed, high sensitivity, and good stability.

[0032] The ADC is used to convert the weak electrical signal output by the photodiode into a digital signal for subsequent digital processing. The conversion accuracy and speed of the ADC have an important impact on the performance of the infrared receiving module.

[0033] The LED driving module is used to drive the infrared light-emitting diode in the infrared transmitting module. It adjusts the current and voltage of the infrared light-emitting diode according to the instructions of the controller to ensure its normal operation and emit infrared optical signals that meet the requirements.

[0034] The DSP is the core processing unit in the infrared receiving module, used to decode, analyze, and process the digital signal output by the ADC. The DSP has powerful computing capabilities and a flexible programming interface, and can be customized and developed according to actual needs. The role of the DSP is to convert the received infrared signal into instructions or data that can be recognized by the controller, realizing functions such as remote control or data transmission.

[0035] The I2C communication module is responsible for realizing data communication between the components inside the infrared receiving module and between the infrared receiving module and external devices.

[0036] The I2C communication module adopts a master-slave structure, which includes one master device and one or more slave devices. The master device is responsible for controlling the communication process, while the slave devices passively accept the control of the master device and perform data transmission and reception. The working principle of the I2C communication module mainly includes the following steps:

[0037] Start signal: The master device first sends a start signal to indicate the start of communication. This start signal is the state where the SDA line changes from high level to low level while the SCL line remains high level.

[0038] Device address and read / write bit: The master device then sends the address of the slave device and the read / write bit. The address is used to specify the slave device to communicate with, and the read / write bit indicates whether the subsequent data transmission is a read operation or a write operation.

[0039] Slave device response: After receiving the address, the specified slave device will compare its own address with the received address. If they are the same, the slave device will send an acknowledgment signal (ACK) to indicate readiness for data transmission. If they are different, the slave device will remain silent.

[0040] Data transmission: The master device and the slave device perform data transmission through the SDA line and the SCL line. During data transmission, the SCL line is used to transmit the clock signal, and the SDA line is used to transmit the data signal. The data is transmitted bit by bit under the synchronization of the clock signal.

[0041] Stop signal: When the data transmission is completed, the master device will send a stop signal to indicate the end of communication. This stop signal is the state where the SDA line changes from low level to high level while the SCL line also changes to high level.

[0042] The I2C communication module mainly plays the following roles in the infrared receiving circuit:

[0043] Data transmission: The I2C communication module realizes two-way data transmission through the serial data line (SDA) and the serial clock line (SCL). It can transmit the data collected by sensors such as CMOS image sensors and photodiodes to the digital processing unit DSP, and at the same time, DSP can also send control instructions to the LED driving module through the I2C communication module.

[0044] Device control: The I2C communication module supports a multi-master system, can establish connections between the master device and the slave devices, and realizes the control of the slave devices. In the infrared receiving circuit, the master device (such as DSP) can send control instructions to the slave device (such as the LED driving module) through the I2C communication module to adjust parameters such as the brightness and blinking frequency of the LED.

[0045] System Expansion: The I2C communication module has high scalability and can be easily connected to multiple slave devices to expand the functions of the system. In the infrared receiving circuit, multiple sensors can be connected through the I2C communication module to improve the detection and data processing capabilities of the system.

[0046] The infrared emission module includes an infrared light-emitting diode and a driving circuit. The infrared light-emitting diode is a semiconductor device that can convert electrical energy into infrared light energy. The wavelength of the infrared light it emits is usually between 0.76 and 1.5 μm, belonging to the category of invisible light. The driving circuit is used to provide stable current and voltage to ensure the normal operation of the infrared light-emitting diode. The function of the infrared emission module is to convert an electrical signal into an infrared light signal and send it out. When the driving circuit receives an instruction from the controller, it will drive the infrared light-emitting diode to emit infrared light of the corresponding frequency. When the infrared light propagates in the air and encounters an obstacle, it will be reflected or scattered, thus realizing remote communication.

[0047] Figure 2 It is a schematic connection diagram of the infrared emission module in the infrared sending and receiving circuit of the present utility model. As Figure 2 shown, pin 1 of the infrared emission chip U1 is respectively connected to one end of the filtering capacitor C1 and one end of the resistor R1. The other end of the filtering capacitor C1 is grounded. The other end of the resistor R1 is connected to the positive electrode of the infrared light-emitting diode D1. The negative electrode of the infrared light-emitting diode D1 is connected to pin 6 of the infrared emission chip U1.

[0048] Figure 4 It is a schematic connection diagram of the infrared receiving module in the infrared sending and receiving circuit of the present utility model. The infrared receiving module further includes a preamplifier, a filtering circuit, a demodulation circuit, and an output circuit. The preamplifier is used to amplify the electrical signal; the filtering circuit is used to filter out clutter interference; the demodulation circuit is used to restore the modulated signal to the original signal; and the output circuit outputs the demodulated signal to the controller for processing.

[0049] The function of the infrared receiving module is to receive an infrared light signal and convert it into an electrical signal. When the infrared light signal irradiates on the photodiode, a weak current signal will be generated. After being processed by the preamplifier and the filtering circuit, the signal is restored to the original signal by the demodulation circuit. Finally, the output circuit outputs the demodulated signal to the controller for processing to realize functions such as remote control or data transmission.

[0050] The power control module includes a power detection circuit, a voltage regulation circuit, and a current protection circuit. These three parts cooperate with each other to jointly realize the monitoring, regulation, and protection of the power supply.

[0051] The power supply detection circuit is mainly responsible for real-time monitoring of the power supply, and detecting whether parameters such as the power supply voltage and current are normal. The power supply detection circuit includes: a voltage detection circuit and a first comparison circuit. The voltage detection circuit converts the power supply voltage into a voltage signal suitable for processing by the comparison circuit through a voltage-dividing resistor; the first comparison circuit compares the detected voltage and current signals with a preset threshold value to determine whether the power supply state is normal.

[0052] The voltage adjustment circuit is responsible for making necessary adjustments to the power supply voltage according to the results of the power supply detection circuit. The voltage adjustment circuit includes: a reference voltage source, an error amplifier, and a power adjustment transistor. The reference voltage source provides a stable reference voltage; the error amplifier compares the detected power supply voltage with the reference voltage to generate an error signal; the power adjustment transistor adjusts the output voltage according to the error signal to make it stable near the preset value. Through the action of the voltage adjustment circuit, it can be ensured that the infrared transmission and reception circuit can still work normally when the power supply voltage fluctuates.

[0053] The current protection circuit is mainly responsible for limiting and protecting the current in the circuit to prevent damage to circuit components due to excessive current. The current protection circuit includes: a current detection circuit and a second comparison circuit. The current detection circuit detects the magnitude of the current in the circuit and converts the current signal into a voltage signal; the second comparison circuit compares the detected current signal with a preset threshold value to determine whether the current exceeds the limit. In specific implementation, if the current exceeds the limit, a current drive circuit can also be set up, and the current drive circuit cuts off the power supply in the power supply control module to protect the circuit components from damage.

[0054] The LED drive module includes: an LED driver, a current limiter, a temperature detection circuit, and a protection circuit. The LED driver is the core component of the LED drive module, and it is responsible for converting the voltage and current provided by the power supply control module into the voltage and current suitable for the infrared LED to work. The LED driver usually adopts a constant current drive method to ensure that the infrared LED has a stable luminous intensity and lifespan under different working conditions. The current limiter is used to limit the current flowing through the infrared LED to prevent it from being damaged due to overcurrent. The current limiter usually uses a resistor or a current source to implement, and its resistance value or output current is selected according to the working parameters of the infrared LED and the output ability of the LED driver. The temperature detection circuit is used to monitor the working temperature of the infrared LED in real time. When the temperature of the infrared LED is too high, the temperature detection circuit sends a signal to the LED driver to make it reduce the output voltage and current, so as to avoid damage to the infrared LED due to overheating. The protection circuit is used to protect the LED drive module and the infrared LED from damage under abnormal conditions. In specific implementation, the protection circuit can include overvoltage protection, overcurrent protection, overheat protection, and short-circuit protection, etc. When an abnormal situation occurs, the protection circuit immediately cuts off the power supply or reduces the output voltage and current to ensure the safety of the LED drive module and the infrared LED.

[0055] The LED driving module plays a crucial role in the infrared transmitting and receiving circuit. It mainly has the following functions:

[0056] Provide stable power supply: The LED driving module provides a stable power supply voltage for the infrared LED through the power control module, ensuring that it emits light stably within the normal operating voltage range.

[0057] Precisely control the current: The LED driver adopts a constant current driving method to ensure that the infrared LED has a stable luminous intensity and lifespan under different operating conditions.

[0058] Real-time monitor the temperature: The temperature detection circuit monitors the operating temperature of the infrared LED in real time to prevent it from being damaged due to overheating.

[0059] Provide protection function: The protection circuit cuts off the power supply or reduces the output voltage and current in case of abnormalities, protecting the LED driving module and the infrared LED from damage.

[0060] The filter circuit includes: a capacitor C1 and a resistor R1 connected in series.

[0061] The functions of the filter circuit in the infrared receiving module are mainly reflected in the following aspects:

[0062] Filter out interference signals: Infrared signals are prone to various interferences during transmission, such as electromagnetic interference, thermal noise, etc. The filter circuit can effectively filter out these interference signals and improve the signal quality.

[0063] Retain useful signals: The filter circuit can selectively retain the useful signal components according to the characteristics of the infrared signal, ensuring that the subsequent circuit can correctly process these signals.

[0064] Improve system performance: By optimizing the design of the filter circuit, the performance of the infrared receiving module can be improved, such as improving the receiving sensitivity, reducing the bit error rate, etc.

[0065] In the infrared receiving module, the filter circuit usually adopts a band-pass filter. The band-pass filter allows signals within a certain frequency range to pass through while suppressing signals of other frequencies. This is because infrared signals usually have a certain frequency range, such as between 30 kHz and 60 kHz. The band-pass filter can selectively pass signals within this range while filtering out interference signals of other frequencies.

[0066] Specifically, when the infrared signal enters the filtering circuit, it is first amplified by the preamplifier. Then, these signals enter the band-pass filter. In the filter, high-frequency and low-frequency interference signals are suppressed, while the useful infrared signals are retained and passed through. Finally, the filtered signals enter the demodulation circuit for demodulation processing to restore the original signal at the transmitting end.

[0067] During specific implementation, the demodulation circuit may include: a transistor M1, a resistor R2, and a capacitor C2 connected in series. The demodulation circuit is a process of restoring the modulated signal to the original signal. In the infrared receiving module, the demodulation circuit is mainly responsible for demodulating the received infrared signal and restoring it to the original signal waveform at the transmitting end.

[0068] The working principle of the present utility model is as follows: The power supply is connected to the 6th pin of the integrated infrared receiving tube U2 through the current-limiting resistor R0 and the infrared transmitting tube U1. The power supply is connected to the 1st pin of the infrared receiving tube U2 through the filtering capacitor C1 to provide a stable working power supply. The 2nd pin of the infrared receiving tube U2 is for the internal detection of the 38KHZ carrier pulse and can be externally connected with an LED indicator for indicating the circuit operation. The 3rd and 4th pins of the infrared receiving tube U2 are SCL and SDA respectively, which are I2C communication interfaces. The external MCU can read the proximity sensing ADC data through the I2C interface. The receiving chip can be set to support the interrupt function, eliminating the need for polling to read the sensor data, thereby improving the application efficiency. Through I2C communication, the I2C interface can be connected to a group of registers to control the infrared transmitting module and the infrared receiving module, or output data, so as to calculate the difference between the non-exposed image value and the average value of the exposed images, and judge the proximity sensing state according to the difference. When a hand or an object approaches the sensing area directly above the sensor, the indicator light turns on, and when the hand or the object leaves the sensing area directly above the sensor, the sensing state indicator light turns off.

[0069] Through the design of the above embodiments of the present utility model, the beneficial effects are as follows: By setting the infrared transmitting module, the infrared receiving module, the current-limiting resistor R0, and the filtering capacitor C1 connected electrically, the infrared receiving module is provided with a power control module, a CMOS image sensor, a photodiode, an ADC, an LED driving module, an I2C communication module, and a digital processing unit DSP; the structure is simple, the cost is low, the anti-interference ability is strong, it can be freely adjusted according to the brightness of the ambient light, and it has a wide sensing range and high sensitivity; it can be widely applied to intelligent multi-functional induction faucets, induction sanitary wares, induction hand dryers, trash cans, soap dispensers, air dryers, urinals, and can be extended to applications in medical treatment, street lights, corridors, balconies, kitchens, bathrooms, warehouses, elevator entrances, children's rooms, hotel corridors, and utility rooms, etc., where automatic opening and closing are required.

[0070] The present utility model is described according to specific embodiments, but those skilled in the art should understand that various changes and equivalent substitutions can be made without departing from the scope of the present utility model. In addition, many modifications can be made to the present utility model to adapt to specific situations of the technology of the present utility model without departing from its protection scope. Therefore, the present utility model is not limited to the specific embodiments disclosed herein, but includes all embodiments falling within the protection scope of the claims.

Claims

1. An infrared transmitting and receiving circuit, characterized in that: include: Through the electrically connected infrared transmitting module, infrared receiving module, current limiting resistor R0 and filter capacitor C1, the infrared receiving module is provided with a power control module, a CMOS image sensor, a photodiode, an ADC, an LED driving module, an I2C communication module and a digital processing unit DSP, the infrared transmitting module is used to transmit infrared signals, the infrared receiving module receives and decodes the infrared signals to realize remote control or data transmission functions, the current limiting resistor is used to limit the current size to prevent components from being damaged; the filter capacitor is used to filter out clutter interference and improve signal quality, the photodiode is used to receive the infrared signal and convert it into an electrical signal, the I2C communication module is used to transmit the data collected by the CMOS image sensor and the photodiode to the digital processing unit DSP, and is also used to send the control instructions received from the digital processing unit DSP to the LED driving module.

2. The infrared transmitting and receiving circuit according to claim 1, characterized in that: The infrared emission module comprises an infrared light emitting diode and a driving circuit.

3. The infrared transmitting and receiving circuit according to claim 1, characterized in that: The infrared receiving module also includes a preamplifier, a filter circuit, a demodulation circuit and an output circuit. The preamplifier is used to amplify the electrical signal; the filter circuit is used to filter out clutter interference; the demodulation circuit is used to restore the modulated signal to the original signal; and the output circuit outputs the demodulated signal to the controller for processing.

4. The infrared transmitting and receiving circuit according to claim 1, characterized in that: The power control module includes a power detection circuit, a voltage adjustment circuit and a current protection circuit.

5. The infrared transmitting and receiving circuit according to claim 1, characterized in that: The LED driving module includes: an LED driver, a current limiter, a temperature detection circuit and a protection circuit.

6. The infrared transmitting and receiving circuit according to claim 3, characterized in that: The filter circuit includes: a capacitor C1 and a resistor R1 connected in series.

7. The infrared transmitting and receiving circuit according to claim 3, characterized in that: The demodulation circuit includes: a transistor M1, a resistor R2 and a capacitor C2 connected in series.

8. The infrared transmitting and receiving circuit according to claim 4, characterized in that: The power detection circuit includes: a voltage detection circuit and a first comparison circuit.

9. The infrared transmitting and receiving circuit according to claim 4, characterized in that: The voltage regulating circuit includes: a reference voltage source, an error amplifier and a power regulating tube.

10. The infrared transmitting and receiving circuit according to claim 4, characterized in that: The current protection circuit includes: a current detection circuit and a second comparison circuit.

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