Proximity light detection circuit and proximity light sensor

Abstract

The application provides a proximity light detection circuit and a proximity light sensor. The proximity light detection circuit comprises a proximity light detection module and a controller module. The proximity light detection module comprises a time-of-flight signal processing chip, a photodiode and a light-emitting diode connected to the time-of-flight signal processing chip. In the proximity light detection circuit, the use of the time-of-flight signal processing chip reduces the analog circuit components in the circuit, the overall structure of the circuit is simpler, and the circuit consistency is extremely high, so that the circuit is more suitable for batch production and use.

Description

Technical Field

[0001] This application relates to the field of object proximity detection, and in particular to a proximity light detection circuit and a proximity light sensor. Background Technology

[0002] Currently, proximity sensors are widely used in various smart device technologies to detect the distance between objects and devices, thereby enabling intelligent adjustment and control functions. Known proximity sensors for detecting the distance between objects and devices typically consist of a sensor chip circuit that internally includes components such as light-emitting diodes (LEDs), photodiodes (PDs), operational amplifiers, MOSFETs, and ADC chips. The LED emits light, which is reflected by the object being measured. The closer an object gets, the stronger the reflected light becomes, allowing the sensor chip circuit to determine the proximity of the object based on the intensity of the reflected light received by the PD.

[0003] However, the sensor chip circuit has a large number of analog circuit components, the circuit structure is relatively complex, the circuit consistency is poor, and there are obvious limitations in mass production and use. Summary of the Invention

[0004] To address the existing technical problems, this application provides a proximity light detection circuit and proximity light sensor with a simple structure, fewer analog circuit components, high circuit consistency, and suitability for mass production.

[0005] In a first aspect, embodiments of this application provide a proximity light detection circuit, including:

[0006] The proximity light detection module includes a time-of-flight signal processing chip, a photodiode connected to the time-of-flight signal processing chip, and a light-emitting diode;

[0007] The controller module is connected to the proximity light detection module.

[0008] In a second aspect, a proximity light sensor is provided, including the proximity light detection circuit described in any embodiment of this application.

[0009] The proximity light detection circuit provided in the above embodiment is designed to be divided into a proximity light detection module and a controller module. The proximity light detection module, by using a time-of-flight signal processing chip in conjunction with a photodiode and an LED, can modulate the current to drive the LED to emit light, thereby adaptively reducing the interference of ambient light. It can also convert the light signal received by the photodiode into a current signal and send it to the controller module. The controller module further processes the signal to obtain an accurate current signal value, thereby achieving a more precise distance measurement. In this proximity light detection circuit, the use of a time-of-flight signal processing chip reduces the number of analog circuit components, resulting in a simpler overall circuit structure and extremely high circuit consistency, making it more suitable for mass production.

[0010] The proximity light sensor provided in the above embodiments belongs to the same concept as the corresponding proximity light detection circuit embodiments, and thus has the same technical effect as the corresponding proximity light detection circuit embodiments, which will not be repeated here. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of a proximity light detection circuit in one embodiment.

[0012] Figure 2 This is a circuit diagram of a proximity light detection circuit in one embodiment.

[0013] Figure 3 This is a schematic diagram of a proximity light sensor in one embodiment. Detailed Implementation

[0014] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0015] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0016] In the following description, the phrase "some embodiments" refers to a subset of all possible embodiments. It should be noted that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0017] In the following description, the terms "first, second, and third" are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, and third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0018] Please see Figure 1 The proximity light detection circuit provided in one embodiment of this application includes: a proximity light detection module 10, including a time-of-flight signal processing chip U1, a photodiode D1 and a light-emitting diode D2 connected to the time-of-flight signal processing chip U1; and a controller module 20 connected to the proximity light detection module 10.

[0019] The controller module 20 includes an MCU controller U2. The proximity light detection module 10 and the controller module 20 can be two relatively independent packaged chip modules. The time-of-flight signal processing chip U1 is a dedicated integrated circuit used to measure the flight time of light or signal between transmission and reception. In this embodiment, the time-of-flight signal processing chip U1 works in conjunction with photodiode D1 and light-emitting diode D2. The time-of-flight signal processing chip U1 controls the emission of light from light-emitting diode D2 and processes the reflected light signal received by photodiode D1 to achieve the proximity light detection function.

[0020] The controller module 20 is connected to the proximity light detection module 10 and can be used to control the working state of the proximity light detection module 10, as well as to receive and process the detection results. By dividing the proximity light detection module 10 and the controller module 20 into two relatively independent packaged chip modules, different types of proximity light detection modules 10 can be formed using light-emitting diodes D2 and photodiodes D1 with different wavelength ranges. The controller module 20 can be combined with different types of proximity light detection modules 10 to meet the application requirements of replacing light-emitting diodes D2 and photodiodes D1 with different wavelength ranges and sizes in different application scenarios.

[0021] In the above embodiments, the proximity light detection circuit is designed to be divided into a proximity light detection module 10 and a controller module 20. The proximity light detection module 10, by using a time-of-flight signal processing chip U1 in conjunction with a photodiode D1 and an LED D2, can modulate the current to drive the LED D2 to emit light, thereby adaptively reducing the interference of ambient light. It can also convert the light signal received by the photodiode D1 into a current signal and send it to the controller module 20. The controller module 20 further processes the signal to obtain an accurate current signal value, thereby achieving a more precise distance measurement. In this proximity light detection circuit, the use of the time-of-flight signal processing chip U1 reduces the use of analog circuit components in the circuit, making the overall circuit structure simpler and the circuit consistency extremely high, thus making it more suitable for mass production.

[0022] In some embodiments, please refer to Figure 2 The controller module 20 communicates via I 2 It connects to the proximity light detection module 10 via C communication. 2The C-mode communication uses a data cable to achieve communication between the controller module 20 and the proximity light detection module 10, resulting in a more stable and reliable communication method. Optionally, the controller module 20 and the proximity light detection module 10 are each formed as a packaged module, and each has a connector interface for line insertion. Utilizing the connector interface, the controller module 20 and the proximity light detection module 10 can be more easily connected or disconnected by plugging and unplugging the lines, facilitating replacement. In a specific example, the controller module 20 is connected to the data line pins, clock line pins, interrupt signal pins, and start detection pins of the time-of-flight signal processing chip U1 via lines to achieve precise control and data interaction with the proximity light detection module 10.

[0023] Optionally, the time-of-flight signal processing chip U1 includes a built-in digital-to-analog converter (DAC). An LED D2 emits light, and a photodiode D1 receives the light signal reflected back from the target based on the light emitted by the LED D2. The DAC converts the light signal into a current signal and sends it to the controller module 20. The built-in DAC in the time-of-flight signal processing chip U1 can control the light intensity of the LED D2, flexibly adjusting its power according to different detection requirements and environmental conditions to improve detection accuracy and reliability. When the LED D2 emits light, and the light shines on the target and is reflected back, the photodiode D1 receives the reflected light signal. The time-of-flight signal processing chip U1 converts the received light signal into a current signal and sends it to the controller module 20 for subsequent analysis and judgment.

[0024] Optionally, LED D2 is connected to the control output pin EIR of the time-of-flight signal processing chip U1. The proximity detection module 10 also includes a filter circuit 11 connected to the power supply pin of the time-of-flight signal processing chip U1. The power supply pin includes a power supply pin and a power ground pin. The filter circuit 11 includes filter capacitors C1 and C2 connected to the power supply pin, a first filter bead FB1, and a second filter bead FB4 connected to the power ground pin. LED D2 and filter capacitors C1 and C2 are connected to form a first electrical junction 110, which is connected to the power ground through the second filter bead FB4. The time-of-flight signal processing chip U1 connects to LED D2 through its control output pin EIR to control the light emission of LED D2. The design of the filter circuit 11 on the power supply pin and the design of LED D2 multiplexing the second filter bead FB4 can effectively suppress power supply noise and improve the stability of the LED D2 signal.

[0025] Optionally, the power supply pins of the time-of-flight signal processing chip U1 include digital power pins DVCC and DVSS, analog power pins AVCC and AVSS, and transmitter power pins EVCC and EVSS. Different types of power pins, namely digital power pins DVCC and DVSS, analog power pins AVCC and AVSS, and transmitter power pins EVCC and EVSS, are each connected to a filter circuit 11 with essentially the same design. Taking the filter circuit 11 connected to the transmitter power pins EVCC and EVSS as an example, filter capacitors C1 and C2 are connected in parallel and connected to the power supply pin EVCC in the transmitter power supply. An LED D2 is connected to filter capacitors C1 and C2 to form a first electrical junction 110. The first electrical junction 110 is connected to the power ground through a second filter bead FB4 connected to the power ground pin EVSS in the transmitter power supply.

[0026] Taking the filter circuit 11 connected to the digital power pins DVCC and DVSS as an example, filter capacitors C5 and C7 are connected in parallel, and one end is connected to the power ground pin DVSS in the digital power pin. The other end of the filter capacitors C5 and C7 connected in parallel is connected to the power supply pin DVCC in the digital power pin to form an electrical node. This electrical node, that is, the power supply pin DVCC in the digital power pin, is connected to the power supply voltage source VCC_3V3 through the third filter bead FB3.

[0027] Taking the filter circuit 11 at the analog power supply pins AVCC and AVSS as an example, filter capacitors C4 and C6 are connected in parallel, and one end is connected to the power ground pin AVSS in the analog power supply pins. The other end of the filter capacitors C5 and C7 are connected in parallel and connected to the power supply pin AVCC in the analog power supply pins to form an electrical node. This electrical node, that is, the power supply pin AVCC in the analog power supply pins, is connected to the power supply voltage source VCC_3V3 through the fifth filter bead FB2.

[0028] Multiple power supply pin types can meet the power requirements of different functional modules, and the filter circuit 11 designed at each type of power supply pin can effectively reduce power supply noise and improve the accuracy and stability of signal processing. Optionally, pull-up resistors R1, R2, R3, R6, and R7 are connected to each pin connected to the power supply terminal, and pull-down resistors R4 and R5 are connected to each pin connected to the ground electrode to ensure stable circuit operation.

[0029] Please see Figure 3In another aspect, this application also provides a proximity light sensor 30, which includes a proximity light detection circuit according to any embodiment of this application. This proximity light sensor 30 can encapsulate the proximity light detection circuit in a compact sensor structure, forming a complete detection unit that can be easily integrated into various electronic devices. The controller module 20 and the proximity light detection module 10 are connected in a pluggable manner via wiring, further improving the sensor's flexibility and maintainability.

[0030] The controller module 20 and the proximity light detection module 10 are connected in a pluggable manner via a line; the proximity light detection module 10 includes different models of proximity light detection modules 10 formed based on photodiodes D1 and light-emitting diodes D2 with different wavelength ranges.

[0031] The controller module 20 and the proximity light detection module 10 adopt a relatively independent modular design. The controller module 20 and the proximity light detection module 10 are each formed as packaged modules and each has a connector structure for wiring, allowing for easier connection and separation between the two modules via wiring. This facilitates rapid integration and replacement in different application scenarios. Furthermore, the proximity light detection module 10 includes different models of proximity light detection modules 10 based on photodiodes D1 and light-emitting diodes D2 with different wavelength ranges. Appropriate combinations of photodiodes D1 and light-emitting diodes D2 with suitable wavelength ranges can be selected according to specific application requirements to achieve optimal detection results. For example, in some applications, it may be necessary to detect light within a specific wavelength range; by selecting the appropriate module model, the sensitivity and accuracy of the detection can be improved.

[0032] As can be seen from the above embodiments, the proximity light detection circuit and proximity light sensor 30 provided in this application have at least the following characteristics:

[0033] First, the proximity light detection circuit adopts a modular design concept. The controller module 20 and the proximity light detection module 10 are each formed as packaged modules, which can be connected by plug-and-play wiring. The proximity light detection module 10 can be based on different models corresponding to photodiodes D1 and light-emitting diodes D2 with different wavelength ranges. Therefore, according to different application scenarios and detection requirements, different proximity light detection modules with specific wavelength ranges can be selected to form the proximity light sensor 30 corresponding to the proximity light detection circuit connected to the controller module 20 for detection. By selecting the appropriate module model, the sensitivity and accuracy of detection can be improved. This modular design not only improves the flexibility and maintainability of the sensor, but also facilitates rapid integration into different devices and systems.

[0034] Secondly, in the proximity light detection module 10, a time-of-flight signal processing chip U1 works in conjunction with photodiode D1 and light-emitting diode D2. By utilizing the time-of-flight signal processing chip U1, the current can be modulated to drive the light-emitting diode D2 to emit light, adaptively reducing ambient light interference. This reduces the use of analog circuit components, resulting in a simpler overall circuit structure and extremely high circuit consistency, making it more suitable for mass production. The controller module 20 can access the sensor via I / O. 2 The C-mode communication method enables precise control and data interaction of the proximity light detection module 10 without the need for additional algorithm correction, and is more suitable for batch use.

[0035] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0036] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A proximity light detection circuit, characterized in that, include: The proximity light detection module includes a time-of-flight signal processing chip, a photodiode connected to the time-of-flight signal processing chip, and a light-emitting diode; The controller module is connected to the proximity light detection module; The controller module and the proximity light detection module are each formed as an encapsulation module, and the controller module and the proximity light detection module are each provided with a connector interface for line insertion.

2. The proximity light detection circuit according to claim 1, characterized in that, The controller module is connected to the proximity light detection module via I²C communication.

3. The proximity light detection circuit according to claim 2, characterized in that, The controller module is connected to the data line pins, clock line pins, interrupt signal pins, and start detection pins of the time-of-flight signal processing chip via circuitry.

4. The proximity light detection circuit according to claim 3, characterized in that, The time-of-flight signal processing chip includes a built-in digital-to-analog conversion circuit. The light-emitting diode is used to emit light, the photodiode receives the light signal reflected back from the target object based on the light emitted by the light-emitting diode, and the digital-to-analog converter circuit converts the light signal into a current signal and sends it to the controller module.

5. The proximity light detection circuit according to claim 1, characterized in that, The light-emitting diode is connected to the control output pin of the time-of-flight signal processing chip, and the proximity light detection module also includes a filter circuit connected to the power supply pin of the time-of-flight signal processing chip; The power supply pin includes a power supply pin and a power ground pin, and the filter circuit includes a filter capacitor and a first filter bead connected to the power supply pin, and a second filter bead connected to the power ground pin. The light-emitting diode is connected to the filter capacitor to form a first electrical junction, and the first electrical junction is connected to the power supply ground through the second filter bead.

6. The proximity light detection circuit according to claim 5, characterized in that, The power pins include digital power pins, analog power pins, and transmitter power pins; The light-emitting diode is connected to the filter capacitor on the power supply pin of the transmitter power supply pin to form the first electrical junction. The first electrical junction is connected to the power ground through the second filter bead connected to the power ground pin of the transmitter power supply pin.

7. The proximity light detection circuit according to claim 1, characterized in that, Each pin of the time-of-flight signal processing chip connected to the power supply terminal is equipped with a pull-up resistor.

8. A proximity light sensor, characterized in that, Includes the proximity light detection circuit as described in any one of claims 1 to 7.

9. The proximity light sensor according to claim 8, characterized in that, The controller module and the proximity light detection module are connected in a pluggable manner via a wire; The proximity light detection module includes different models of proximity light detection modules formed based on the photodiodes and light-emitting diodes with different wavelength ranges.

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