Infrared detection circuit, method, device and apparatus

Abstract

This application relates to an infrared detection circuit, method, apparatus, and device. When an infrared signal is received by an infrared receiver, power is supplied to ground through the infrared receiver and a sampling resistor. A corresponding voltage signal is detected at the sampling resistor and coupled to an inverting integrator circuit for integration, yielding a signal of the magnitude of a first voltage signal. This signal is then transmitted to a hysteresis comparator circuit for comparison, ultimately outputting a square wave signal of the magnitude of a second voltage signal to the processor, which identifies the signal. The processor determines the frequency of the output square wave signal based on the first and second voltage signals and then determines the infrared signal intensity based on the frequency, thus achieving infrared signal intensity detection. During operation, this scheme can convert infrared signals of different intensities into square wave signals of corresponding frequencies, thereby enabling the processor to detect infrared signal intensity based on the frequency of the received square wave signal.

Description

Technical Field

[0001] This application relates to the field of infrared detection technology, and in particular to an infrared detection circuit, method, apparatus and equipment. Background Technology

[0002] With the development of science and technology, infrared technology is increasingly being used in fields such as security monitoring, automotive night vision systems, medical devices, communications, and home electronics, bringing great convenience to people's daily lives.

[0003] Traditional infrared detection methods directly receive infrared signals through an infrared receiver tube and trigger an infrared operation upon sensing the signal. However, this method can only distinguish the presence of an infrared signal, but cannot identify the strength of the signal. Summary of the Invention

[0004] Therefore, it is necessary to address the problem that traditional infrared detection methods cannot identify the strength of infrared signals by providing an infrared detection circuit, method, device, and equipment that can convert infrared signals of different intensities into square wave signals of corresponding frequencies, thereby enabling the detection of infrared signal strength at the processor based on the frequency of the output square wave signal of the received square wave signal.

[0005] An infrared detection circuit includes: an infrared receiver, a sampling resistor, an inverting integrator circuit, a hysteresis comparator circuit, and a processor. A first terminal of the infrared receiver is connected to a power supply, and a second terminal of the infrared receiver is connected to a first terminal of the sampling resistor, the second terminal of the sampling resistor being grounded. A first terminal of the inverting integrator circuit is connected to both the second terminal of the infrared receiver and the first terminal of the sampling resistor, and a second terminal of the inverting integrator circuit is also connected to the second terminal of the sampling resistor. A third terminal of the inverting integrator circuit is connected to both the first terminal of the hysteresis comparator circuit and the second terminal of the hysteresis comparator circuit. The processor is used to obtain the frequency of an output square wave signal based on a first voltage signal output from the third terminal of the inverting integrator circuit and a second voltage signal output from the third terminal of the hysteresis comparator circuit, and to determine the intensity of an infrared signal based on the frequency of the output square wave signal.

[0006] In one embodiment, the sampling resistor is an adjustable resistor.

[0007] In one embodiment, the infrared detection circuit further includes a first capacitor, and the first terminal of the inverting integrator circuit is connected to the second terminal of the infrared receiver tube and the first terminal of the sampling resistor through the first capacitor.

[0008] In one embodiment, the inverting integrator circuit includes a first operational amplifier, a first resistor, a second resistor, and a second capacitor. The first input terminal of the first operational amplifier is connected to the first terminal of the first resistor and the first terminal of the second capacitor. The second terminal of the first resistor is connected to the second terminal of the infrared receiver and the first terminal of the sampling resistor. The second terminal of the second capacitor is connected to the output terminal of the first operational amplifier and the first terminal of the hysteresis comparator circuit. The second input terminal of the first operational amplifier is connected to the first terminal of the second resistor, and the second terminal of the second resistor is connected to the second terminal of the sampling resistor.

[0009] In one embodiment, the hysteresis comparator circuit includes a second operational amplifier, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor. The first input terminal of the second operational amplifier is connected to the first terminal of the third resistor and the first terminal of the fourth resistor. The second terminal of the third resistor is connected to the third terminal of the inverting integrator circuit. The second terminal of the fourth resistor is connected to the output terminal of the operational amplifier circuit and the first terminal of the fifth resistor. The second terminal of the fifth resistor is connected to the processor. The second input terminal of the second operational amplifier is connected to the first terminal of the sixth resistor. The second terminal of the sixth resistor is connected to the second terminal of the inverting integrator circuit.

[0010] In one embodiment, the infrared detection circuit further includes a protection circuit, wherein a first terminal of the protection circuit is connected to the processor and a third terminal of the hysteresis comparator circuit, and a second terminal of the protection circuit is connected to a second terminal of the hysteresis comparator circuit.

[0011] In one embodiment, the protection circuit includes a first Zener diode and a second Zener diode, the anode of the first Zener diode is connected to the anode of the second Zener diode, the cathode of the first Zener diode is connected to the processor and the third terminal of the hysteresis comparator circuit, and the cathode of the second Zener diode is connected to the second terminal of the hysteresis comparator circuit.

[0012] In one embodiment, the infrared detection circuit further includes a voltage regulating device, the input of which is connected to the fourth terminal of the inverting integrator circuit and the third terminal of the hysteresis comparator circuit, and the output of which is connected to the processor.

[0013] An infrared detection method based on any one of the infrared detection circuits described above includes: acquiring a first voltage signal output from the third terminal of the inverting integrator circuit and a second voltage signal output from the third terminal of the hysteresis comparator circuit; obtaining the frequency of an output square wave signal based on the first voltage signal and the second voltage signal; and determining the intensity of an infrared signal based on the frequency of the output square wave signal.

[0014] In one embodiment, determining the infrared signal intensity based on the frequency of the output square wave signal includes: determining whether an infrared triggering condition is met based on the frequency of the output square wave signal; if the infrared triggering condition is met, then analyzing the infrared signal intensity based on the frequency of the output square wave signal.

[0015] In one embodiment, determining whether the infrared triggering condition is met based on the frequency of the output square wave signal includes: detecting whether the frequency of the output square wave signal is greater than or equal to a preset frequency threshold; if the frequency of the output square wave signal is greater than or equal to the preset frequency threshold, then the infrared triggering condition is considered to be met.

[0016] In one embodiment, the step of obtaining the infrared signal intensity based on the frequency of the output square wave signal if the infrared triggering condition is met includes: if the infrared triggering condition is met, obtaining the infrared signal intensity by matching the frequency of the output square wave signal and a preset frequency-infrared signal intensity correspondence.

[0017] An infrared detection device based on any one of the infrared detection circuits described above includes: a signal acquisition module for acquiring a first voltage signal output from the third terminal of the inverting integrator circuit and a second voltage signal output from the third terminal of the hysteresis comparator circuit; a frequency analysis module for obtaining the frequency of an output square wave signal based on the first voltage signal and the second voltage signal; and an intensity analysis module for determining the intensity of an infrared signal based on the frequency of the output square wave signal.

[0018] An infrared detection device includes the infrared detection circuit described in any one of the above claims, wherein the processor executes the steps of the infrared detection method described in any one of the above claims.

[0019] In the aforementioned infrared detection circuit, method, apparatus, and device, when an infrared signal is received by an infrared receiver, the power supply is connected to ground through the infrared receiver and a sampling resistor. A corresponding voltage signal is detected at the sampling resistor and coupled to an inverting integrator circuit for integration, yielding a signal of the magnitude of a first voltage signal. This signal is then transmitted to a hysteresis comparator circuit for comparison, ultimately outputting a square wave signal of the magnitude of a second voltage signal to the processor, which is then recognized by the processor. The processor determines the frequency of the output square wave signal based on the first and second voltage signals and determines the infrared signal intensity based on the frequency, thus achieving infrared signal intensity detection. During operation, this scheme can convert infrared signals of different intensities into square wave signals of corresponding frequencies, thereby enabling the processor to detect infrared signal intensity based on the frequency of the received square wave signal. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the infrared detection circuit structure in one embodiment of this application;

[0022] Figure 2 This is a schematic diagram of the infrared detection circuit structure in another embodiment of this application;

[0023] Figure 3 This is a schematic diagram of the infrared detection circuit structure in another embodiment of this application;

[0024] Figure 4 This is a schematic diagram of the infrared detection circuit structure in another embodiment of this application;

[0025] Figure 5 This is a schematic diagram of the infrared detection circuit structure in another embodiment of this application;

[0026] Figure 6 This is a schematic diagram of the infrared detection method in one embodiment of this application;

[0027] Figure 7 This is a schematic diagram of the infrared detection method in another embodiment of this application;

[0028] Figure 8 This is a schematic diagram of the infrared detection method in another embodiment of this application;

[0029] Figure 9 This is a schematic diagram of the infrared detection method in another embodiment of this application;

[0030] Figure 10 This is a schematic diagram of the voltage waveform received by the processor in one embodiment of this application;

[0031] Figure 11 This is a schematic diagram of the voltage waveform received by the processor in another embodiment of this application;

[0032] Figure 12 This is a schematic diagram of the infrared detection device in one embodiment of this application. Detailed Implementation

[0033] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0034] Please see Figure 1 An infrared detection circuit includes: an infrared receiver tube Tg, a sampling resistor R, an inverting integrator circuit 110, a hysteresis comparator circuit 120, and a processor 130. The first terminal of the infrared receiver tube Tg is connected to a power supply, and the second terminal of the infrared receiver tube Tg is connected to the first terminal of the sampling resistor R, with the second terminal of the sampling resistor R grounded. The first terminal of the inverting integrator circuit 110 is connected to the second terminal of the infrared receiver tube Tg and the first terminal of the sampling resistor R, and the second terminal of the inverting integrator circuit 110 is connected to the second terminal of the sampling resistor R. The third terminal of the inverting integrator circuit 110 is connected to the first terminal of the hysteresis comparator circuit 120, and the second terminal of the hysteresis comparator circuit 120 is connected to the second terminal of the inverting integrator circuit 110. The processor 130 is connected to the third terminal of the hysteresis comparator circuit 120 and the third terminal of the inverting integrator circuit 110 (not shown). The processor 130 is used to obtain the frequency of an output square wave signal based on the first voltage signal output by the inverting integrator circuit 110 and the second voltage signal output by the hysteresis comparator circuit 120, and to determine the intensity of the infrared signal based on the frequency of the output square wave signal.

[0035] Specifically, the infrared receiver Tg is a switching device that receives infrared signals and converts them into electrical signals. The inverting integrator circuit 110 and the hysteresis comparator circuit 120 together constitute the operational circuit. After the infrared receiver Tg receives the infrared signal, the power supply voltage flows to ground through the infrared switch and the sampling resistor R. The voltage is detected at the sampling resistor R and coupled to the inverting integrator circuit 110. The inverting integrator circuit 110 performs integration processing and finally outputs a voltage signal of the magnitude of the first voltage signal to the hysteresis comparator circuit 120.

[0036] After receiving a voltage signal of the magnitude of the first voltage signal, the hysteresis comparator circuit 120 performs a corresponding comparison operation and outputs a square wave signal to the processor 130. The processor 130 identifies the square wave signal, performs corresponding calculations, and obtains the frequency of the output square wave signal. Finally, the processor 130 determines the intensity of the detected infrared signal based on the calculated frequency of the output square wave signal.

[0037] It should be noted that the specific type of infrared receiver Tg is not unique. In a more detailed embodiment, the infrared receiver Tg is an infrared transistor. The first end of the infrared transistor is connected to the power supply, the second end is connected to the first end of the first resistor R1, and the control end is used to receive infrared signals.

[0038] It is understood that the type of processor 130 is not unique; any processor 130 capable of receiving square wave signals is acceptable. For example, in a more detailed embodiment, the processor 130 is a microcontroller. In this embodiment, after processing by the inverting integrator circuit 110 and the hysteresis comparator circuit 120, the infrared signal is converted into a square wave signal that the microcontroller can recognize and receive. This allows the microcontroller to perform infrared detection operations, thereby improving the reliability of infrared detection.

[0039] Further, in one embodiment, the processor analyzes and calculates the frequency of the output square wave signal based on the first voltage signal, the second voltage signal, and a preset frequency calculation model. The preset frequency calculation model represents the correspondence between the first voltage signal, the second voltage signal, and the frequency of the output square wave signal. Depending on the acquired first or second voltage signal, the final calculated frequency of the square wave signal will also differ. After infrared signals of different intensities are received by the infrared receiver Tg, the voltage at the sampling resistor R will also differ, resulting in differences in the first voltage signal ultimately coupled to the inverting integrator 110 for integration calculation and output, and the second voltage signal output by the hysteresis comparator 120 after comparison calculation based on the first voltage signal. Therefore, the processor 130 can determine the corresponding infrared signal intensity based on the actually calculated frequency of the output square wave signal.

[0040] During actual operation, the processor 130 needs to detect and acquire the first voltage signal from the inverting integrator circuit 110 and the second voltage signal from the hysteresis comparator circuit 120 in real time. The specific acquisition method is not unique. In one embodiment, the processor 130 can integrate a voltage detection function internally. Simply connecting the third terminals of the inverting integrator circuit 110 and the hysteresis comparator circuit 120 to the processor 130 respectively enables the detection of the first and second voltage signals. In another embodiment, voltage detection devices can be set at the output terminals of the inverting integrator circuit 110 and the hysteresis comparator circuit 120 respectively, transmitting the detected first and second voltage signals to the processor 130.

[0041] After obtaining the infrared signal strength, the processor 130 can further combine the infrared signal strength to achieve distance detection, etc. There are no specific limitations; it can be selected according to actual needs.

[0042] In the aforementioned infrared detection circuit, when the infrared signal is received by the infrared receiver Tg, the power supply is connected to ground through the infrared receiver Tg and the sampling resistor R. A corresponding voltage signal is detected at the sampling resistor R and coupled to the inverting integrator circuit 110 for integration, obtaining a signal of the magnitude of the first voltage signal. This signal is then transmitted to the hysteresis comparator circuit 120 for comparison, ultimately outputting a square wave signal of the magnitude of the second voltage signal to the processor 130, which is then recognized by the processor 130. The processor 130 determines the frequency of the output square wave signal based on the first and second voltage signals and determines the infrared signal intensity based on the output square wave signal frequency, thus achieving infrared signal intensity detection. During operation, this scheme can convert infrared signals of different intensities into square wave signals of corresponding frequencies, thereby enabling the processor 130 to detect the infrared signal intensity based on the frequency of the received square wave signal.

[0043] In one embodiment, the sampling resistor R is an adjustable resistor.

[0044] Specifically, the actual value of the sampling resistor R affects the detection accuracy and distance of the infrared detection circuit. Different resistance values ​​of the sampling resistor R result in different currents flowing through it, ultimately leading to different signal strengths. A smaller resistance value results in a weaker signal, while a larger resistance value results in a stronger signal. Therefore, in this embodiment, the sampling resistor R can be set as an adjustable resistor. In practical applications, adjusting the actual resistance value of the sampling resistor R can change the detection accuracy and distance of the infrared detection circuit, effectively improving its application range and operational reliability.

[0045] Please see Figure 2 In one embodiment, the infrared detection circuit further includes a first capacitor C1, and the first terminal of the inverting integrator circuit 110 is connected to the second terminal of the infrared receiver tube Tg and the first terminal of the sampling resistor R through the first capacitor C1.

[0046] Specifically, the selection of the first capacitor C1 is related to the transmission frequency of the infrared signal received by the infrared receiving tube Tg. In the technical solution of this application, an operational amplifier is used to receive the infrared signal. The operational amplifier has a high-impedance input, meaning it can identify small signals. In this embodiment, a first capacitor C1 is also provided between the first terminal of the inverting integrator circuit 110 and the first terminal of the sampling resistor R. The first capacitor C1 isolates the interference of ambient light, allowing the true infrared pulse to pass through, while isolating DC components such as the power supply. Through this solution, it can be ensured that the signal coupled to the inverting integrator circuit 110 does not contain DC components such as the isolated power supply, further improving the accuracy of infrared detection.

[0047] It should be noted that the specific type of the inverting integrator circuit 110 is not unique; for a more detailed embodiment, please refer to [link / reference needed]. Figure 3 The inverting integrator circuit 110 includes a first operational amplifier OP1, a first resistor R1, a second resistor R2, and a second capacitor C2. The first input terminal of the first operational amplifier OP1 is connected to the first terminal of the first resistor R1 and the first terminal of the second capacitor C2. The second terminal of the first resistor R1 is connected to the second terminal of the infrared receiver Tg and the first terminal of the sampling resistor R. The second terminal of the second capacitor C2 is connected to the output terminal of the first operational amplifier OP1 and the first terminal of the hysteresis comparator circuit 120. The second input terminal of the first operational amplifier OP1 is connected to the first terminal of the second resistor R2, and the second terminal of the second resistor R2 is connected to the second terminal of the sampling resistor R.

[0048] Specifically, the output voltage of the inverting integrator circuit 110 is integrally related to the input voltage. The basic operational relationship of the inverting integrator circuit 110, which is composed of an operational amplifier, is as follows: when the input of the inverting integrator circuit 110 is a constant DC voltage, the output voltage changes linearly with time, and its rising and falling slopes change with the changes of the first resistor R1, the second resistor R2, the second capacitor C2, and the input voltage.

[0049] In this embodiment, the inverting integrator circuit 110 is built based on the first operational amplifier OP1. The second terminal of the first resistor R1 serves as the first terminal of the inverting integrator circuit 110, the second terminal of the second resistor R2 serves as the second terminal of the inverting integrator circuit 110, and the output terminal of the first operational amplifier OP1 serves as the third terminal of the inverting integrator circuit 110, thus realizing related signal processing functions. Further, in a more detailed embodiment, the first input terminal of the first operational amplifier OP1 is the inverting input terminal, and the second input terminal of the first operational amplifier OP1 is the non-inverting input terminal.

[0050] Please refer to the following: Figure 3 In one embodiment, the hysteresis comparator circuit 120 includes a second operational amplifier OP2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6. The first input terminal of the second operational amplifier OP2 is connected to the first terminal of the third resistor R3 and the first terminal of the fourth resistor R4. The second terminal of the third resistor R3 is connected to the third terminal of the inverting integrator circuit 110. The second terminal of the fourth resistor R4 is connected to the output terminal of the operational amplifier circuit and the first terminal of the fifth resistor R5. The second terminal of the fifth resistor R5 is connected to the processor 130 (not shown). The second input terminal of the second operational amplifier OP2 is connected to the first terminal of the sixth resistor R6. The second terminal of the sixth resistor R6 is connected to the second terminal of the inverting integrator circuit 110.

[0051] Specifically, the hysteresis comparator circuit 120, also known as a Schmitt trigger or hysteresis comparator, is characterized by having two unequal thresholds when the input signal gradually increases or decreases, exhibiting a hysteresis curve in its transmission characteristics. In this embodiment, the second terminal of the third resistor R3 is used as the first terminal of the hysteresis comparator circuit 120, the second terminal of the sixth resistor R6 is used as the second terminal of the hysteresis comparator circuit 120, and the second terminal of the fifth resistor R5 is used as the third terminal of the hysteresis comparator circuit 120.

[0052] In a more detailed embodiment, the inverting integrator circuit 110 includes a first operational amplifier OP1, a first resistor R1, a second resistor R2, and a second capacitor C2, and the hysteresis comparator circuit 120 includes a second operational amplifier OP2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6. Accordingly, in this embodiment, the second terminal of the third resistor R3 is connected to the second terminal of the second capacitor C2 and the output terminal of the first operational amplifier OP1; the second terminal of the sixth resistor R6 is connected to the second terminal of the second resistor R2.

[0053] In this embodiment, the high threshold of the hysteresis comparator circuit 120 is U. TH1 The low threshold is U TH2 The rectangular wave peak value of the voltage Uout output by the hysteresis comparator circuit 120 is ±Uz (i.e., the second voltage signal), and the output of the inverting integrator circuit 110 is a sawtooth wave. Their basic relationship is U... TH2 =-R3Uz / R4;U TH1 =R3Uz / R4; where R3 is the resistance of the third resistor R3, and R4 is the resistance of the fourth resistor R4. The forward operating period T1 of the hysteresis comparator circuit 120 is = 2R3R1C2Uz / (R4Ui), while the retrace operating period T2 is much smaller than the forward operating period T1. Therefore, the frequency of the output square wave signal can be approximated as: f = 1 / T = 1 / T1 = R4Ui / (2R3R1C2Uz); where R3 is the resistance of the third resistor R3, R4 is the resistance of the fourth resistor R4, R1 is the resistance of the first resistor R1, C2 is the capacitance of the second capacitor C2, Ui is the first voltage signal output by the inverting integrator circuit 110, and Uz is the second voltage signal of the hysteresis comparator circuit 120.

[0054] Based on the above structure, in a more detailed embodiment, the preset frequency calculation model can be set as: f = R4Ui / (2R3R1C2Uz). In the preset frequency calculation model, all resistor and capacitor values ​​are fixed parameters and can be stored in the processor 130 in a preset format. Therefore, in actual operation, the processor 130 only needs to substitute the acquired first voltage signal and second voltage signal into the preset frequency calculation model to quickly calculate the corresponding output square wave signal frequency.

[0055] Please see Figure 4 In one embodiment, the infrared detection circuit further includes a protection circuit 140, the first end of which is connected to the processor 130 (not shown) and the third end of the hysteresis comparison circuit 120, and the second end of which is connected to the second end of the hysteresis comparison circuit 120.

[0056] Specifically, in this embodiment, a protection circuit 140 is provided between the hysteresis comparator circuit 120 and the processor 130 to protect the processor 130 and ensure its safe operation.

[0057] It should be noted that the specific type of protection circuit 140 is not unique; please refer to a more detailed embodiment for further details. Figure 4 The protection circuit 140 includes a first Zener diode D2 and a second Zener diode D3. The anode of the first Zener diode D2 is connected to the anode of the second Zener diode D3. The cathode of the first Zener diode D2 is connected to the processor 130 and the third terminal of the hysteresis comparator circuit 120. The cathode of the second Zener diode D3 is connected to the second terminal of the hysteresis comparator circuit 120.

[0058] Specifically, a Zener diode, also known as a Zener diode, utilizes the reverse breakdown state of a PN junction, where the current can vary over a wide range while the voltage remains essentially constant, thus achieving voltage regulation. This embodiment uses two Zener diodes connected in reverse series to protect the processor 130, offering advantages such as simple structure and ease of implementation.

[0059] Furthermore, in one embodiment, please refer to [reference needed]. Figure 4 The infrared detection circuit also includes a first diode D1, wherein the anode of the first diode D1 is connected to the first terminal of the second capacitor and the first input terminal of the first operational amplifier OP1, and the cathode of the first diode D1 is connected to the second terminal of the fifth resistor R5 and the cathode of the first Zener diode D2. In this embodiment, the first diode D1 provides a discharge path for the infrared detection circuit, further improving the operational reliability of the infrared detection circuit.

[0060] Please see Figure 5 In one embodiment, the infrared detection circuit further includes a voltage regulator 150, the input of which is connected to the third terminal of the hysteresis comparator circuit 120, and the output of which is connected to the processor 130.

[0061] Specifically, in the technical solution of this application, the infrared signal is received by the infrared receiving tube Tg, and after integration and comparison processing by the operational amplifier circuit, the resulting voltage value is generally large, while the operating voltage of the processor 130 is generally small. Therefore, in actual operation, the second voltage signal output by the hysteresis comparator circuit 120 is often higher than the operating voltage of the processor 130. In order to ensure that the processor 130 can receive a suitable voltage to perform the relevant infrared detection operations, this embodiment also provides a voltage regulating device 150 at the front end of the processor 130 to adjust the voltage output by the hysteresis comparator circuit 120.

[0062] For example, in a more detailed embodiment, the processor 130 is a microcontroller, which generally operates on a 3.3V or 5V system. Using the infrared detection circuit of this application, the output signal reaches 16V at the infrared receiver tube Tg, which exceeds the microcontroller's operating voltage. At this time, other proportional voltage reduction methods such as resistor voltage division can be used to proportionally reduce the voltage flowing into the microcontroller to a range that the microcontroller can recognize. For example, a 4x voltage reduction can be used to proportionally reduce 16V to 4V, or 12V can be proportionally reduced to 3V to ensure that the microcontroller can safely detect.

[0063] It is understood that in other embodiments, the voltage regulating device 150 may also be of other types, as long as the voltage ultimately transmitted to the processor 130 meets the operating voltage requirements of the processor 130. For example, optocouplers, switching transistors, etc., may also be used to achieve the voltage reduction function.

[0064] Please see Figure 6 An infrared detection method based on any one of the above infrared detection circuits includes steps 602, 604 and 606.

[0065] Step 602: Obtain the first voltage signal output from the third terminal of the inverting integrator circuit and the second voltage signal output from the third terminal of the hysteresis comparator circuit; Step 604: Obtain the frequency of the output square wave signal based on the first voltage signal and the second voltage signal; Step 606: Determine the infrared signal intensity based on the frequency of the output square wave signal.

[0066] Specifically, the infrared receiver is a switching device that receives infrared signals and converts them into electrical signals. The inverting integrator circuit and the hysteresis comparator circuit together constitute the operational circuit. After the infrared receiver receives the infrared signal, the power supply voltage flows to ground through the infrared switch and the sampling resistor. It is detected at the sampling resistor and coupled to the inverting integrator circuit, where it is integrated and finally outputs a voltage signal of the magnitude of the first voltage signal to the hysteresis comparator circuit.

[0067] After receiving a voltage signal of the magnitude of the first voltage signal, the hysteresis comparator circuit performs a comparison operation and outputs a square wave signal to the processor. The processor identifies the square wave signal and performs calculations based on a preset frequency calculation model to obtain the frequency of the output square wave signal. Finally, the processor determines the intensity of the detected infrared signal based on the calculated frequency of the output square wave signal.

[0068] It should be noted that the specific type of infrared receiver tube is not unique. In a more detailed embodiment, the infrared receiver tube is an infrared transistor. The first end of the infrared transistor is connected to the power supply, the second end is connected to the first end of the first resistor, and the control end is used to receive infrared signals.

[0069] It is understood that the type of processor is not unique; any processor capable of receiving square wave signals will suffice. For example, in a more detailed embodiment, the processor is a microcontroller. In this embodiment, the infrared signal is converted into a square wave signal that the microcontroller can recognize and receive after processing by an inverting integrator circuit and a hysteresis comparator circuit. This allows the microcontroller to perform infrared detection operations, thereby improving the reliability of infrared detection.

[0070] Further, in one embodiment, the processor analyzes and calculates the frequency of the output square wave signal based on the first voltage signal, the second voltage signal, and a preset frequency calculation model. The preset frequency calculation model represents the correspondence between the first voltage signal, the second voltage signal, and the frequency of the output square wave signal. Depending on the acquired first or second voltage signal, the final calculated frequency of the square wave signal will also differ. After infrared signals of different intensities are received by the infrared receiver, the voltage at the sampling resistor will also differ, resulting in differences in the first voltage signal ultimately coupled to the inverting integrator circuit for integration calculation and output, and the second voltage signal output by the hysteresis comparator circuit after comparison calculation based on the first voltage signal. Therefore, the processor can determine the corresponding infrared signal intensity based on the actually calculated frequency of the output square wave signal.

[0071] During actual operation, the processor needs to detect and acquire the first voltage signal from the inverting integrator circuit and the second voltage signal from the hysteresis comparator circuit in real time. The specific method for acquiring these signals is not unique. In one embodiment, the processor can integrate voltage detection functionality internally; simply connecting the third terminals of the inverting integrator circuit and the hysteresis comparator circuit to the processor allows for the detection of both the first and second voltage signals. In another embodiment, voltage detection devices can be placed at the output terminals of the inverting integrator circuit and the hysteresis comparator circuit, respectively, to transmit the detected first and second voltage signals to the processor.

[0072] In the aforementioned infrared detection method, when the infrared signal is received by the infrared receiver, the power supply is connected to ground through the infrared receiver and the sampling resistor. A corresponding voltage signal is detected at the sampling resistor and coupled to an inverting integrator circuit for integration, yielding a first voltage signal. This first voltage signal is then transmitted to a hysteresis comparator circuit for comparison, ultimately outputting a square wave signal of the second voltage signal magnitude to the processor, which then identifies it. The processor determines the frequency of the output square wave signal based on the first and second voltage signals and uses this frequency to determine the infrared signal intensity, thus achieving infrared signal intensity detection. During operation, this scheme can convert infrared signals of different intensities into square wave signals of corresponding frequencies, allowing the processor to detect infrared signal intensity based on the frequency of the received square wave signal.

[0073] It should be noted that the specific form of the preset frequency calculation model is not unique and will vary depending on the actual circuit structure of the inverting integrator circuit and the hysteresis comparator circuit. For example, in a more detailed embodiment, the inverting integrator circuit includes a first operational amplifier, a first resistor, a second resistor, a second capacitor, and a diode, and the hysteresis comparator circuit includes a second operational amplifier, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor. Correspondingly, the preset frequency calculation model is f = R4Ui / (2R3R1C2Uz), where R3 is the resistance value of the third resistor, R4 is the resistance value of the fourth resistor, R1 is the resistance value of the first resistor, C2 is the capacitance value of the second capacitor, Ui is the first voltage signal output by the inverting integrator circuit, and Uz is the second voltage signal of the hysteresis comparator circuit.

[0074] Please see Figure 7 In one embodiment, step 606 includes steps 702 and 704.

[0075] Step 702: Determine whether the infrared triggering condition is met based on the frequency of the output square wave signal; Step 704: If the infrared triggering condition is met, analyze the infrared signal intensity based on the frequency of the output square wave signal.

[0076] Specifically, the processor calculates the output square wave signal frequency based on the first and second voltage signals. It then checks whether the infrared triggering conditions are met based on the output square wave signal frequency. Only if the infrared triggering conditions are met will the infrared signal intensity analysis operation be further performed; otherwise, there is no need to perform infrared signal intensity analysis. This embodiment of the scheme can further improve the reliability of infrared detection.

[0077] It should be noted that the method for detecting whether the infrared triggering conditions are met is not unique. For a more detailed embodiment, please refer to [link / reference needed]. Figure 8 Step 702 includes step 802.

[0078] Step 802: Detect whether the frequency of the output square wave signal is greater than or equal to the preset frequency threshold.

[0079] Specifically, if the frequency of the output square wave signal is greater than or equal to a preset frequency threshold, the infrared triggering condition is considered met. The processor pre-stores the preset frequency threshold corresponding to this infrared detection circuit. During actual detection, after analyzing and calculating the frequency of the output square wave signal, the preset frequency threshold and the output square wave signal frequency are compared and analyzed. When the frequency of the output square wave signal is greater than or equal to the preset frequency threshold, the infrared triggering condition is considered met, meaning the received infrared signal is a valid trigger. Conversely, when the frequency of the output square wave signal is less than the preset frequency threshold, the detected infrared signal is considered not to meet the triggering condition, meaning it is an invalid trigger.

[0080] It is understandable that the preset frequency threshold is not unique. Depending on the actual use case and the different triggering precision of infrared detection, different settings can be made. There is no specific limitation.

[0081] Please see Figure 9 In one embodiment, step 704 includes step 902.

[0082] Step 902: If the infrared triggering condition is met, the infrared signal strength is obtained by matching the output square wave signal frequency and the preset frequency-infrared signal strength correspondence.

[0083] Specifically, please refer to the following: Figure 10 In one embodiment, when the infrared signal received by the infrared receiver is weak, the corresponding output square wave signal frequency is 33kHz. Please refer to [link to relevant documentation]. Figure 11 When the received infrared signal is strong, the output square wave signal frequency is 55kHz. Multiple tests revealed that in this embodiment's infrared detection circuit, the output square wave signal frequency changes proportionally to the received infrared signal intensity; the stronger the received infrared signal, the higher the corresponding output square wave signal frequency. Therefore, a correspondence between frequency and infrared signal intensity can be established through actual measurement and stored in the processor. During actual infrared intensity analysis, simply substituting the calculated output square wave signal frequency into the preset frequency-infrared signal intensity correspondence directly yields the corresponding infrared signal intensity.

[0084] To facilitate understanding of the technical solution of this application, the following detailed embodiments will be used to explain and illustrate this application.

[0085] The specific circuit structure of the infrared detection circuit is as follows: Figure 4As shown (processor diagram not shown), when an infrared signal is detected, the power supply VCC flows back to ground through the infrared receiver Tg and the sampling resistor R. At this time, a signal is acquired at the sampling resistor R. This signal, after the DC component of the power supply is filtered out by the first capacitor C1, is coupled to the inverting integrator circuit 110. After integration by the inverting integrator circuit 110, a signal Ui of the magnitude of the first voltage signal is output to the hysteresis comparator circuit 120. After comparison and calculation at the hysteresis comparator circuit 120, a square wave signal of the magnitude of the second voltage signal (±Uz) is finally output to the processor. The processor calculates the frequency of the output square wave signal based on the first voltage signal, the second voltage signal, and the preset frequency calculation model f = R4Ui / (2R3R1C2Uz). Then, it determines whether the frequency of the output square wave signal is greater than or equal to a preset frequency threshold. If it is greater than or equal to the preset frequency threshold, it is considered a valid infrared trigger. The processor will then further match the infrared signal intensity according to the preset frequency-infrared signal intensity correspondence to complete the infrared detection.

[0086] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0087] Based on the same inventive concept, this application also provides an infrared detection device for implementing the infrared detection method described above. The solution provided by this device is similar to the implementation described in the above method; therefore, the specific limitations in one or more infrared detection device embodiments provided below can be found in the limitations of the infrared detection method described above, and will not be repeated here.

[0088] In one embodiment, such as Figure 12 As shown, an infrared detection device is provided, including a signal acquisition module 122, a frequency analysis module 124, and an intensity analysis module 126.

[0089] The signal acquisition module 122 is used to acquire the first voltage signal output from the third terminal of the inverting integrator circuit and the second voltage signal output from the third terminal of the hysteresis comparator circuit; the frequency analysis module 124 is used to obtain the frequency of the output square wave signal based on the first voltage signal and the second voltage signal; the intensity analysis module 126 is used to determine the intensity of the infrared signal based on the frequency of the output square wave signal.

[0090] In one embodiment, the intensity analysis module 126 is further configured to determine whether the infrared triggering condition is met based on the frequency of the output square wave signal; if the infrared triggering condition is met, the intensity of the infrared signal is obtained by analyzing the frequency of the output square wave signal.

[0091] In one embodiment, the intensity analysis module 126 is further used to detect whether the frequency of the output square wave signal is greater than or equal to a preset frequency threshold.

[0092] In one embodiment, the intensity analysis module 126 is further configured to, if the infrared triggering condition is met, match the infrared signal intensity according to the frequency of the output square wave signal and the preset frequency-infrared signal intensity correspondence.

[0093] Each module in the aforementioned infrared detection device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0094] In the aforementioned infrared detection device, when the infrared signal is received by the infrared receiver, the power supply is connected to ground through the infrared receiver and the sampling resistor. A corresponding voltage signal is detected at the sampling resistor and coupled to an inverting integrator circuit for integration, yielding a first voltage signal. This first voltage signal is then transmitted to a hysteresis comparator circuit for comparison, ultimately outputting a square wave signal of the second voltage signal magnitude to the processor, which then identifies it. The processor determines the frequency of the output square wave signal based on the first and second voltage signals and uses this frequency to determine the infrared signal intensity, thus achieving infrared signal intensity detection. During operation, this scheme can convert infrared signals of different intensities into square wave signals of corresponding frequencies, allowing the processor to detect infrared signal intensity based on the frequency of the received square wave signal.

[0095] An infrared detection device includes an infrared detection circuit according to any one of the above-mentioned methods, and a processor executes the steps of any one of the above-mentioned infrared detection methods.

[0096] Specifically, the specific structure of the infrared detection circuit and the specific steps of the infrared detection method are as shown in the above embodiments. The inverting integrator circuit and the hysteresis comparator circuit together constitute the operational circuit. After the infrared receiver tube receives the infrared signal, the power supply voltage flows to ground through the infrared switch tube and the sampling resistor. It is detected at the sampling resistor and coupled to the inverting integrator circuit. The inverting integrator circuit performs integration processing and finally outputs a voltage signal of the magnitude of the first voltage signal to the hysteresis comparator circuit.

[0097] After receiving a voltage signal of the magnitude of the first voltage signal, the hysteresis comparator circuit performs a comparison operation and outputs a square wave signal to the processor. The processor identifies the square wave signal, performs corresponding calculations, and obtains the frequency of the output square wave signal. Finally, the processor determines the intensity of the detected infrared signal based on the calculated frequency of the output square wave signal.

[0098] During actual operation, the processor needs to detect and acquire the first voltage signal from the inverting integrator circuit and the second voltage signal from the hysteresis comparator circuit in real time. The specific method for acquiring these signals is not unique. In one embodiment, the processor can integrate voltage detection functionality internally; simply connecting the outputs of the inverting integrator circuit and the hysteresis comparator circuit to the processor respectively enables the detection of the first and second voltage signals. In another embodiment, voltage detection devices can be placed at the outputs of the inverting integrator circuit and the hysteresis comparator circuit, respectively, to transmit the detected first and second voltage signals to the processor.

[0099] It should be noted that the specific type of infrared detection device is not unique. For example, in a more detailed embodiment, the infrared detection device may specifically be a home appliance such as an air conditioner, refrigerator, or robot vacuum cleaner with infrared detection function.

[0100] In the aforementioned infrared detection device, when an infrared signal is received by the infrared receiver, the power supply is connected to ground through the infrared receiver and a sampling resistor. A corresponding voltage signal is detected at the sampling resistor and coupled to an inverting integrator circuit for integration, yielding a first voltage signal. This first voltage signal is then transmitted to a hysteresis comparator circuit for comparison, ultimately outputting a square wave signal of a second voltage signal magnitude to the processor, which then identifies it. The processor determines the frequency of the output square wave signal based on the first and second voltage signals and uses this frequency to determine the infrared signal intensity, thus achieving infrared signal intensity detection. During operation, this scheme converts infrared signals of different intensities into square wave signals of corresponding frequencies, allowing the processor to detect infrared signal intensity based on the frequency of the received square wave signal.

[0101] The technical features of the above embodiments 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. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0102] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An infrared detection circuit, characterized in that, include: Infrared receiver tube; A sampling resistor is provided, with the first end of the infrared receiving tube connected to a power supply, the second end of the infrared receiving tube connected to the first end of the sampling resistor, and the second end of the sampling resistor grounded. An inverting integrating circuit, wherein the first terminal of the inverting integrating circuit is connected to the second terminal of the infrared receiving tube and the first terminal of the sampling resistor, and the second terminal of the inverting integrating circuit is connected to the second terminal of the sampling resistor; A hysteresis comparator circuit, wherein the third terminal of the inverting integrator circuit is connected to the first terminal of the hysteresis comparator circuit, and the second terminal of the hysteresis comparator circuit is connected to the second terminal of the inverting integrator circuit; A processor, wherein the processor is connected to the third terminal of the inverting integrator circuit and the third terminal of the hysteresis comparator circuit; The processor is used to obtain the frequency of the output square wave signal based on the first voltage signal output from the third terminal of the inverting integrator circuit and the second voltage signal output from the third terminal of the hysteresis comparator circuit, and to determine the intensity of the infrared signal based on the frequency of the output square wave signal.

2. The infrared detection circuit according to claim 1, characterized in that, The sampling resistor is an adjustable resistor.

3. The infrared detection circuit according to claim 1, characterized in that, It also includes a first capacitor, and the first terminal of the inverting integrator circuit is connected to the second terminal of the infrared receiver tube and the first terminal of the sampling resistor through the first capacitor.

4. The infrared detection circuit according to any one of claims 1-3, characterized in that, The inverting integrator circuit includes a first operational amplifier, a first resistor, a second resistor, and a second capacitor. The first input terminal of the first operational amplifier is connected to the first terminal of the first resistor and the first terminal of the second capacitor. The second terminal of the first resistor is connected to the second terminal of the infrared receiver and the first terminal of the sampling resistor. The second terminal of the second capacitor is connected to the output terminal of the first operational amplifier and the first terminal of the hysteresis comparator circuit. The second input terminal of the first operational amplifier is connected to the first terminal of the second resistor, and the second terminal of the second resistor is connected to the second terminal of the sampling resistor.

5. The infrared detection circuit according to any one of claims 1-3, characterized in that, The hysteresis comparator circuit includes a second operational amplifier, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor. The first input terminal of the second operational amplifier is connected to the first terminal of the third resistor and the first terminal of the fourth resistor. The second terminal of the third resistor is connected to the third terminal of the inverting integrator circuit. The second terminal of the fourth resistor is connected to the output terminal of the operational amplifier circuit and the first terminal of the fifth resistor. The second terminal of the fifth resistor is connected to the processor. The second input terminal of the second operational amplifier is connected to the first terminal of the sixth resistor. The second terminal of the sixth resistor is connected to the second terminal of the inverting integrator circuit.

6. The infrared detection circuit according to claim 1, characterized in that, It also includes a protection circuit, the first end of which is connected to the processor and the third end of the hysteresis comparator circuit, and the second end of which is connected to the second end of the hysteresis comparator circuit.

7. The infrared detection circuit according to claim 6, characterized in that, The protection circuit includes a first Zener diode and a second Zener diode. The anode of the first Zener diode is connected to the anode of the second Zener diode. The cathode of the first Zener diode is connected to the processor and the third terminal of the hysteresis comparator circuit. The cathode of the second Zener diode is connected to the second terminal of the hysteresis comparator circuit.

8. The infrared detection circuit according to claim 1, characterized in that, It also includes a voltage regulating device, the input of which is connected to the third terminal of the hysteresis comparator circuit, and the output of which is connected to the processor.

9. An infrared detection method based on the infrared detection circuit according to any one of claims 1-8, characterized in that, include: Obtain the first voltage signal output from the third terminal of the inverting integrator circuit and the second voltage signal output from the third terminal of the hysteresis comparator circuit; The frequency of the output square wave signal is obtained based on the first voltage signal and the second voltage signal; The infrared signal strength is determined based on the frequency of the output square wave signal.

10. The infrared detection method according to claim 9, characterized in that, Determining the infrared signal intensity based on the frequency of the output square wave signal includes: Determine whether the infrared triggering condition is met based on the frequency of the output square wave signal; If the infrared triggering conditions are met, the infrared signal strength is obtained by analyzing the frequency of the output square wave signal.

11. The infrared detection method according to claim 10, characterized in that, The step of determining whether the infrared triggering condition is met based on the frequency of the output square wave signal includes: The frequency of the output square wave signal is detected to be greater than or equal to a preset frequency threshold; if the frequency of the output square wave signal is greater than or equal to the preset frequency threshold, the infrared triggering condition is considered to be met.

12. The infrared detection method according to claim 10, characterized in that, If the infrared triggering condition is met, the infrared signal strength is obtained by analyzing the frequency of the output square wave signal, including: If the infrared triggering conditions are met, the infrared signal strength is obtained by matching the frequency of the output square wave signal and the preset frequency-infrared signal strength correspondence.

13. An infrared detection device based on the infrared detection circuit according to any one of claims 1-8, characterized in that, include: The signal acquisition module is used to acquire the first voltage signal output from the third terminal of the inverting integrator circuit and the second voltage signal output from the third terminal of the hysteresis comparator circuit. The frequency analysis module is used to obtain the frequency of the output square wave signal based on the first voltage signal and the second voltage signal; The intensity analysis module is used to determine the intensity of the infrared signal based on the frequency of the output square wave signal.

14. An infrared detection device, characterized in that, The processor includes the infrared detection circuit according to any one of claims 1-8, and executes the steps of the infrared detection method according to any one of claims 9-12.

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