DTOF module power supply voltage calibration method, device and system

Abstract

The invention discloses a DTOF module power supply voltage calibration method, device and system, and relates to the technical field of DTOF. According to the invention, the first output voltage output by the first power supply PCB to the DTOF module is adjusted, the first output voltage enabling the DTOF module to start to generate the dark counting rate is stored, the avalanche voltage provided by the first power supply PCB is obtained, and then the second output voltage output by the second power supply PCB to the DTOF module is adjusted. According to the invention, the error of the avalanche voltage provided by the first power supply PCB and the second power supply PCB to the SPAD is small, the distance measurement error of the DTOF module can be reduced, and the distance measurement precision of the DTOF module is improved.

Description

Technical Field

[0001] The present invention relates to the field of DTOF technology, and in particular to a DTOF module power supply voltage calibration method, device and system. Background Art

[0002] The core components of the DTOF (Direct Time of Flight) module include VCSEL (Vertical Cavity Surface Emitting Laser), SPAD (Single Photon Avalanche Diode) and TDC (Time-to-Digital Converter). VCSEL is used to emit pulse waves to the target, SPAD is used to receive pulse waves reflected from the target, and TDC can record the time interval between each emitted pulse and received pulse, that is, the flight time of the light signal. The DTOF module will emit and receive multiple light signals within a single frame measurement time, and then make a histogram statistics of the multiple flight times, and use the flight time with the highest frequency to calculate the depth of the target.

[0003] When the DTOF module is working, the power supply needs to provide a negative voltage (i.e., avalanche voltage Vspad) to the SPAD to cause an avalanche. The size of Vspad will affect the flight time obtained by the TDC, thereby affecting the distance measured by the DTOF module. Errors in the Vspad output by different power supply PCBs (Printed Circuit Boards) will lead to inaccurate distance measurement. Generally, a 128MV Vspad error will cause a 10MM distance measurement change. If the output voltage error of different power supply PCBs is too large, the DTOF module will have inaccurate distance measurement. Therefore, in order to improve the accuracy of the DTOF module's distance measurement, it is necessary to consider how to reduce the output voltage error of different DTOF module power supply PCBs. Summary of the invention

[0004] The present invention solves the technical problem of how to reduce the output voltage error of different DTOF module power supply PCBs by providing a DTOF module power supply voltage calibration method, device and system.

[0005] On the one hand, the present invention provides the following technical solutions:

[0006] A DTOF module power supply voltage calibration method, comprising:

[0007] Adjusting a first output voltage outputted from the first power supply PCB to the DTOF module;

[0008] storing the first output voltage that causes the DTOF module to start generating a dark count rate;

[0009] Adjust the second output voltage output by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than a preset threshold.

[0010] On the other hand, the present invention also provides the following technical solutions:

[0011] A DTOF module power supply voltage calibration device, comprising:

[0012] An adjustment module, used for adjusting a first output voltage outputted from the first power supply PCB to the DTOF module;

[0013] A storage module, used for storing the first output voltage that causes the DTOF module to start generating a dark count rate;

[0014] The adjustment module is also used to adjust the second output voltage output by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than a preset threshold.

[0015] On the other hand, the present invention also provides the following technical solutions:

[0016] A DTOF module power supply voltage calibration system includes a controller, an ADC, a reference voltage source, a first resistance module and a second resistance module;

[0017] The power chip is connected to the controller and the DTOF module respectively, and the power chip is the first power PCB or the second power PCB;

[0018] The output end of the reference voltage source is connected to the output end of the power chip via the first resistance module and the second resistance module connected in series in sequence;

[0019] A common end of the first resistance module and the second resistance module is connected to the controller via the ADC.

[0020] Optionally, the output voltage of the reference voltage source is 1.8V, the resistance of the first resistor module is 6.1k, and the resistance of the second resistor module is 100k.

[0021] Optionally, the model of the power chip is MAX77720.

[0022] On the other hand, the present invention also provides the following technical solutions:

[0023] A DTOF module power supply voltage calibration method, applied to the controller mentioned above, comprises:

[0024] When the power chip is the first power PCB, adjusting the voltage output by the power chip to the DTOF module, reading the output voltage of the ADC and converting it into a first output voltage, and controlling the memory of the DTOF module to store the first output voltage so that the DTOF module starts to generate a dark count rate;

[0025] When the power chip is the second power PCB, the first output voltage stored in the memory is read, the output voltage of the ADC is read and converted into a second output voltage, and the voltage output by the power chip to the DTOF module is adjusted until the difference between the second output voltage and the first output voltage stored in the memory is lower than a preset threshold.

[0026] Optionally, converting the output voltage of the ADC into the first output voltage or the second output voltage includes:

[0027] V0=V2-R2(V1-V2) / R1, V0 is the first output voltage or the second output voltage, V1 is the output voltage of the reference voltage source, V2 is the output voltage of the ADC, R1 is the resistance value of the first resistor module, and R2 is the resistance value of the second resistor module.

[0028] Optionally, the model of the power chip is MAX77720, and adjusting the voltage output from the power chip to the DTOF module includes:

[0029] Adjust the CODE value of the MAX77720 to change its output voltage.

[0030] On the other hand, the present invention also provides the following technical solutions:

[0031] A computer device comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of any DTOF module power supply voltage calibration method.

[0032] On the other hand, the present invention also provides the following technical solutions:

[0033] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of any DTOF module power supply voltage calibration method.

[0034] One or more technical solutions provided by the present invention have at least the following technical effects or advantages:

[0035] The present invention first adjusts the first output voltage output by the first power supply PCB to the DTOF module, stores the first output voltage that enables the DTOF module to start generating a dark count rate, obtains the avalanche voltage provided by the first power supply PCB, and then adjusts the second output voltage output by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than a preset threshold value. This can make the avalanche voltage error provided to the SPAD by the first power supply PCB and the second power supply PCB smaller, thereby reducing the ranging error of the DTOF module and providing the ranging accuracy of the DTOF module. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0037] Figure 1 Flow chart of a DTOF module power supply voltage calibration method according to an embodiment of the present invention;

[0038] Figure 2 Schematic diagram of a DTOF module power supply voltage calibration device in an embodiment of the present invention;

[0039] Figure 3 A schematic diagram of a DTOF module power supply voltage calibration system in an embodiment of the present invention;

[0040] Figure 4 is a circuit diagram of an ADC in an embodiment of the present invention;

[0041] Figure 5 is a circuit diagram of a reference voltage source, a first resistance module, and a second resistance module in an embodiment of the present invention;

[0042] Figure 6 4 is another flow chart of the DTOF module power supply voltage calibration method in an embodiment of the present invention. DETAILED DESCRIPTION

[0043] The embodiments of the present invention solve the technical problem of how to reduce the output voltage error of different DTOF module power supply PCBs by providing a DTOF module power supply voltage calibration method, device and system.

[0044] In order to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0045] like Figure 1 As shown, the DTOF module power supply voltage calibration method of an embodiment of the present invention includes:

[0046] Step S11, adjusting the first output voltage outputted by the first power supply PCB to the DTOF module;

[0047] Step S12, storing a first output voltage that causes the DTOF module to start generating a dark count rate;

[0048] Step S13, adjusting the second output voltage outputted by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than a preset threshold.

[0049] Generally, when the avalanche voltage error of the single photon avalanche diode SPAD output by the first power supply PCB and the second power supply PCB to the DTOF module is large, it will cause a large ranging error of the DTOF module.

[0050] In step S11, the first power supply PCB can be used to provide power for the DTOF module, and the output voltage of the first power supply PCB can be continuously changed; in step S12, the DTOF module begins to generate a dark count rate, indicating that the single-photon avalanche diode SPAD begins to undergo avalanche breakdown, and the first output voltage stored at this time is the avalanche voltage of the SPAD.

[0051] After obtaining the avalanche voltage provided by the first power supply PCB, step S13 can be replaced by using the second power supply PCB to provide power for the DTOF module. The preset threshold value is very small, which may be 15mv. The difference between the second output voltage and the stored first output voltage is lower than the preset threshold, indicating that the avalanche voltage error provided to the SPAD by the first power supply PCB and the second power supply PCB is small. Providing the second output voltage to the DTOF module at this time can reduce the ranging error of the DTOF module.

[0052] Therefore, the DTOF module power supply voltage calibration method of the embodiment of the present invention first adjusts the first output voltage output by the first power supply PCB to the DTOF module, stores the first output voltage that makes the DTOF module start to generate a dark count rate, that is, the avalanche voltage provided by the first power supply PCB, and then adjusts the second output voltage output by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than the preset threshold value. This can make the avalanche voltage error provided to the SPAD by the first power supply PCB and the second power supply PCB smaller, thereby reducing the ranging error of the DTOF module and providing the ranging accuracy of the DTOF module.

[0053] and Figure 1 Corresponding to the DTOF module power supply voltage calibration method, the embodiment of the present invention also provides a DTOF module power supply voltage calibration device, such as Figure 2 As shown, including:

[0054] An adjustment module, used for adjusting a first output voltage outputted from the first power supply PCB to the DTOF module;

[0055] A storage module, used for storing a first output voltage that causes the DTOF module to start generating a dark count rate;

[0056] The adjustment module is also used to adjust the second output voltage output by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than a preset threshold.

[0057] The DTOF module power supply voltage calibration device of the embodiment of the present invention first adjusts the first output voltage output by the first power supply PCB to the DTOF module, stores the first output voltage that causes the DTOF module to start generating a dark count rate, that is, the avalanche voltage provided by the first power supply PCB, and then adjusts the second output voltage output by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than a preset threshold value. This can make the avalanche voltage error provided to the SPAD by the first power supply PCB and the second power supply PCB smaller, thereby reducing the ranging error of the DTOF module and improving the ranging accuracy of the DTOF module.

[0058] To achieve Figure 1 The DTOF module power supply voltage calibration method, the embodiment of the present invention also provides a DTOF module power supply voltage calibration system, such as Figure 3 As shown, it includes a controller, an ADC (Analog-to-Digital Converter), a reference voltage source, a first resistor module and a second resistor module; the power chip is connected to the controller and the DTOF module respectively, and the power chip is a first power PCB or a second power PCB; the output end of the reference voltage source is connected to the output end of the power chip via the first resistor module and the second resistor module connected in series in sequence; the common end of the first resistor module and the second resistor module is connected to the controller via the ADC.

[0059] Since the power chip provides a negative voltage for the SPAD, which is difficult to detect, the voltage at the ADC detection point is made a positive voltage by dividing the reference voltage through the first resistor module and the second resistor module. That is, the output of the reference voltage source, the resistance value of the first resistor module, and the resistance value of the second resistor module must satisfy the requirement that the voltage at the common end of the first resistor module and the second resistor module is a positive voltage. For example, the output voltage of the reference voltage source may be 1.8V, the resistance value of the first resistor module may be 6.1k, and the resistance value of the second resistor module may be 100k. The first resistor module and the second resistor module may use resistors with an accuracy of 0.1%.

[0060] The power chip model can be MAX77720; the ADC circuit can be Figure 4As shown; the circuit diagram of the reference voltage source, the first resistance module and the second resistance module can be as shown Figure 5 shown. Figure 4 , Figure 5 The working principle of the circuit can be found in the corresponding chip manual and will not be introduced here.

[0061] and Figure 3 The DTOF module power supply voltage calibration system corresponds to Figure 6 As shown, the embodiment of the present invention also provides an application Figure 3 A DTOF module power supply voltage calibration method of a controller includes:

[0062] Step S21, when the power chip is the first power PCB, adjust the voltage output from the power chip to the DTOF module, read the output voltage of the ADC and convert it into a first output voltage, and control the memory of the DTOF module to store the first output voltage so that the DTOF module starts to generate a dark count rate;

[0063] Step S22, when the power chip is the second power PCB, read the first output voltage stored in the memory, read the output voltage of the ADC and convert it into the second output voltage, and adjust the voltage output by the power chip to the DTOF module until the difference between the second output voltage and the first output voltage stored in the memory is lower than the preset threshold.

[0064] Among them, converting the output voltage of the ADC into the first output voltage or the second output voltage may include: V0=V2-R2(V1-V2) / R1, V0 is the first output voltage or the second output voltage, V1 is the output voltage of the reference voltage source, V2 is the output voltage of the ADC, R1 is the resistance value of the first resistor module, and R2 is the resistance value of the second resistor module.

[0065] The value of the preset threshold is related to the voltage adjustment step of the power chip. The smaller the voltage adjustment step of the power chip, the smaller the value of the preset threshold. When the model of the power chip is MAX77720, the voltage output from the power chip to the DTOF module is adjusted, including: adjusting the CODE value of MAX77720 to change its output voltage. The voltage adjustment step of MAX77720 is 15mv, so the preset threshold can be 15mv.

[0066] In addition, in order to ensure the accuracy of the output voltage of the power chip, the implementation Figure 6 Before using the method shown, the output voltage of the power chip can be controlled to be a random value. The controller converts the output voltage of the ADC into a voltage corresponding to the random value. Then, a high-precision multimeter is used to directly read the output voltage of the power chip to ensure that the difference between the voltage converted by the controller and the voltage read by the multimeter is lower than a certain threshold, such as 16mv, which is equivalent to testing the power chip first.

[0067] Based on the same inventive concept as the DTOF module power supply voltage calibration method mentioned above, an embodiment of the present invention also provides a computer device, including a memory, a processor and a computer program stored in the memory, and the processor executes the computer program to implement the steps of any one of the DTOF module power supply voltage calibration methods mentioned above.

[0068] Among them, the bus architecture (represented by the bus), the bus can include any number of interconnected buses and bridges, and the bus links various circuits including one or more processors represented by the processor and memory represented by the memory. The bus can also link various other circuits such as peripherals, voltage regulators, and power management circuits together, which are all well known in the art and are therefore not further described herein. The bus interface provides an interface between the bus and the receiver and transmitter. The receiver and transmitter can be the same element, namely a transceiver, which provides a unit for communicating with various other devices on a transmission medium. The processor is responsible for managing the bus and general processing, while the memory can be used to store data used by the processor when performing operations.

[0069] Since the computer device introduced in the embodiment of the present invention is a computer device used to implement the DTOF module power supply voltage calibration method in the embodiment of the present invention, based on the DTOF module power supply voltage calibration method introduced in the embodiment of the present invention, the technical personnel in the field can understand the specific implementation of the computer device in the embodiment of the present invention and its various variations, so how the computer device implements the method in the embodiment of the present invention is not described in detail here. As long as the technical personnel in the field implement the computer device used in the DTOF module power supply voltage calibration method in the embodiment of the present invention, it belongs to the scope of protection of the present invention.

[0070] Based on the same inventive concept as the above-mentioned DTOF module power supply voltage calibration method, the present invention also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above-mentioned DTOF module power supply voltage calibration methods are implemented.

[0071] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0072] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including an instruction device, which implements the functions specified in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0073] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0074] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0075] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A DTOF module power supply voltage calibration method, characterized in that: include: Adjusting a first output voltage outputted from the first power supply PCB to the DTOF module; storing the first output voltage that causes the DTOF module to start generating a dark count rate; Adjust the second output voltage output by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than a preset threshold.

2. A DTOF module power supply voltage calibration device, characterized in that: include: An adjustment module, used for adjusting a first output voltage outputted from the first power supply PCB to the DTOF module; A storage module, used for storing the first output voltage that causes the DTOF module to start generating a dark count rate; The adjustment module is also used to adjust the second output voltage output by the second power supply PCB to the DTOF module until the difference between the second output voltage and the stored first output voltage is lower than a preset threshold.

3. A DTOF module power supply voltage calibration system, characterized in that: It includes a controller, an ADC, a reference voltage source, a first resistance module and a second resistance module; The power chip is connected to the controller and the DTOF module respectively, and the power chip is the first power PCB or the second power PCB; The output end of the reference voltage source is connected to the output end of the power chip via the first resistance module and the second resistance module connected in series in sequence; A common end of the first resistance module and the second resistance module is connected to the controller via the ADC.

4. The DTOF module power supply voltage calibration system as claimed in claim 3, characterized in that: The output voltage of the reference voltage source is 1.8V, the resistance of the first resistor module is 6.1k, and the resistance of the second resistor module is 100k.

5. The DTOF module power supply voltage calibration system as claimed in claim 3, characterized in that: The model of the power chip is MAX77720.

6. A DTOF module power supply voltage calibration method, applied to the controller in claim 3, characterized in that: include: When the power chip is the first power PCB, adjusting the voltage output by the power chip to the DTOF module, reading the output voltage of the ADC and converting it into a first output voltage, and controlling the memory of the DTOF module to store the first output voltage so that the DTOF module starts to generate a dark count rate; When the power chip is the second power PCB, the first output voltage stored in the memory is read, the output voltage of the ADC is read and converted into a second output voltage, and the voltage output by the power chip to the DTOF module is adjusted until the difference between the second output voltage and the first output voltage stored in the memory is lower than a preset threshold.

7. The DTOF module power supply voltage calibration method according to claim 6, characterized in that: Converting the output voltage of the ADC into the first output voltage or the second output voltage includes: V0=V2-R2(V1-V2) / R1, V0 is the first output voltage or the second output voltage, V1 is the output voltage of the reference voltage source, V2 is the output voltage of the ADC, R1 is the resistance value of the first resistor module, and R2 is the resistance value of the second resistor module.

8. The DTOF module power supply voltage calibration method according to claim 6, characterized in that: The model of the power chip is MAX77720, and the voltage output from the power chip to the DTOF module is adjusted, including: Adjust the CODE value of the MAX77720 to change its output voltage.

9. A computer device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method according to any one of claims 1.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 are implemented.

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