Light source driving device and electronic device
Patent Information
- Application Number
- CN202521736448.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2024-09-20
- Filing Date
- 2025-08-15
- Publication Date
- 2026-08-28
- Estimated Expiration
- 2035-08-15
AI Technical Summary
[0002]现有技术中，飞时测距(Time Of Flight；TOF)模块使用定电压校正垂直共振腔面射型激光(Vertical-Cavity Surface-Emitting Laser；VCSEL)的光功率，然而实际状况中可能会有供应电压路径过长，或是印刷电路板(Printed circuit board；PCB)工艺不良等问题，造成供应电压压降，进而使VCSEL输出功率不稳定
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Figure CN224696064U_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to a light source driving device and an electronic device. Background Technology
[0002] In existing technologies, Time-of-Flight (TOF) modules use a constant voltage to correct the optical power of Vertical-Cavity Surface-Emitting Lasers (VCSELs). However, in practice, issues such as excessively long supply voltage paths or poor printed circuit board (PCB) manufacturing processes can cause voltage drops, leading to unstable VCSEL output power. Furthermore, when the detected object is close, the constant voltage TOF module cannot dynamically adjust its power, resulting in excessive power consumption. Utility Model Content
[0003] This disclosure proposes a time-of-flight ranging system with a time-of-flight ranging module design that can dynamically adjust power. It can detect the output power of the light source unit through a power detection unit, and then dynamically adjust the power through feedback control to ensure the stability of the output power of the light source unit. Furthermore, it can dynamically reduce the power when the detection distance is short to achieve the purpose of saving power.
[0004] This disclosure provides a light source driving device, comprising a power supply unit, a time-of-flight ranging module, and a signal processing unit. The power supply unit provides a power source. The time-of-flight ranging module is coupled to the power supply unit and includes a light source unit and a power detection unit. The light source unit has a light source output power. The power detection unit is coupled to the light source unit and stores a preset power and detects the light source output power of the light source unit. The signal processing unit is coupled to the power supply unit and the time-of-flight ranging module and receives a detection signal from the power detection unit. When the light source output power of the light source unit differs from the preset power, the signal processing unit transmits an adjustment signal to adjust the power supply output power of the power supply unit.
[0005] Other embodiments of the aforementioned implementation are as follows: The time-of-flight ranging module further includes a time-of-flight sensor and a driving unit. The time-of-flight sensor is used to receive reflected light from a sensed object and transmit an image signal to a signal processing unit. The driving unit is coupled to the time-of-flight sensor and the light source unit, and includes a driving chip and a transistor. The driving chip is used to receive a transmission light source timing sequence from the time-of-flight sensor and convert the transmission light source timing sequence into an electrical signal. The transistor is coupled to the driving chip. The driving unit controls the transistor to turn on and off to control a signal duty cycle, thereby driving the light source unit to emit a high-frequency modulated laser.
[0006] Other embodiments of the foregoing implementation are as follows: The signal processing unit includes a digital signal processor and a digital resistor chip. The digital signal processor outputs a resistance control signal. The digital resistor chip is connected to the digital signal processor and receives the resistance control signal to generate a corresponding resistor.
[0007] Other embodiments of the foregoing implementation are as follows: The signal processing unit includes a digital signal processor and a filtering circuit. The digital signal processor is used to output a pulse width modulation signal. The filtering circuit is connected to the digital signal processor and is used to suppress interference noise of the pulse width modulation signal.
[0008] Other embodiments of the aforementioned implementation are as follows: the filter circuit is an RC filter circuit or an LC filter circuit.
[0009] Other embodiments of the aforementioned implementation are as follows: The signal processing unit receives the image signal from the time-of-flight sensor and resets the preset power stored in the power detection unit according to the distance of the sensed object.
[0010] Other embodiments of the aforementioned implementation are as follows: The time-of-flight ranging module further includes a connection unit. The connection unit is used to connect the power supply unit, the signal processing unit, the power detection unit, the time-of-flight sensor, and the drive unit.
[0011] An electronic device is provided according to the present disclosure, including the aforementioned light source driving device.
[0012] This disclosure provides a light source driving device, which includes a power supply unit and a time-of-flight ranging module. The power supply unit provides a power source. The time-of-flight ranging module is coupled to the power supply unit and includes a light source unit, a power detection unit, and a power chip. The light source unit has a light source output power. The power detection unit is coupled to the light source unit and stores a preset power and detects the light source output power of the light source unit. The power chip is coupled to the power detection unit and receives the power from the power supply unit, adjusts the power output power, and transmits the power output power to the light source unit. When the light source output power of the light source unit differs from the preset power, the power chip adjusts the power output power.
[0013] Other embodiments of the aforementioned implementation are as follows: The time-of-flight ranging module further includes a time-of-flight sensor and a driving unit. The time-of-flight sensor is used to receive reflected light from a sensed object and transmit an image signal to a signal processing unit. The driving unit is coupled to the time-of-flight sensor and the light source unit, and includes a driving chip and a transistor. The driving chip is used to receive a transmission light source timing sequence from the time-of-flight sensor and convert the transmission light source timing sequence into an electrical signal. The transistor is coupled to the driving chip. The driving unit controls the transistor to turn on and off to control a signal duty cycle, thereby driving the light source unit to emit a high-frequency modulated laser.
[0014] Other embodiments of the aforementioned implementation are as follows: The signal processing unit receives the image signal from the time-of-flight sensor and resets the preset power stored in the power detection unit according to the distance of the sensed object.
[0015] Other embodiments of the aforementioned implementation are as follows: The time-of-flight ranging module further includes a microcontroller unit. The microcontroller unit is coupled to the power detection unit and the power chip, and is used to receive a detection signal from the power detection unit. When the output power of the light source unit is different from the preset power, the microcontroller unit transmits an adjustment signal to control the power chip to adjust the power output power.
[0016] Other embodiments of the aforementioned implementation are as follows: The time-of-flight ranging module further includes a connection unit. The connection unit is used to connect the power supply unit, the signal processing unit, the power detection unit, the time-of-flight sensor, and the power chip.
[0017] Other embodiments of the aforementioned implementation are as follows: the power supply unit is a power module with fixed power.
[0018] An electronic device is provided according to the present disclosure, including the aforementioned light source driving device. Attached Figure Description
[0019] Figure 1 A schematic diagram illustrating the light source driving device according to the first embodiment of the present disclosure is shown;
[0020] Figure 2 Drawing according to Figure 1 A schematic diagram of the dynamic power control process of the light source drive device;
[0021] Figure 3 Drawing according to Figure 1 A schematic diagram of the power detection unit in the first embodiment;
[0022] Figure 4 Drawing according to Figure 1 A schematic diagram of the driving unit in the first embodiment;
[0023] Figure 5A Drawing according to Figure 1 A schematic diagram of the signal processing unit in the first embodiment of the first implementation;
[0024] Figure 5B Drawing according to Figure 1 A schematic diagram of the signal processing unit in the second embodiment of the first implementation;
[0025] Figure 6 A schematic diagram illustrating the light source driving device according to the second embodiment of the present disclosure; and
[0026] Figure 7 A schematic diagram of the light source driving device according to the third embodiment of the present disclosure is shown.
[0027] [Symbol Explanation]
[0028] 100, 200, 300: Light source driving device
[0029] 110: System End
[0030] 111: Power Supply Unit
[0031] 112, 112a, 112b: Signal processing unit
[0032] 1121: Digital Signal Processor
[0033] 1122: Digital Resistor Chip
[0034] 1123: Pull-up resistor
[0035] 1124: Filtering Circuit
[0036] 1125: Voltage divider resistor
[0037] 120: Time-of-Flight Ranging Module
[0038] 121: Light source unit
[0039] 122: Power Detection Unit
[0040] 1221: Power Detection Circuit
[0041] 1222: Memory
[0042] 123: Time-of-flight sensor
[0043] 124: Drive Unit
[0044] 1241: Driver chip
[0045] 1242: Transistor
[0046] 125: Connection Unit
[0047] 126: Power chip
[0048] 127: Microcontroller Unit
[0049] DC: Signal duty cycle
[0050] DP: Preset power
[0051] ES: Electrical signal
[0052] GND: Ground terminal
[0053] P1: Light source output power
[0054] P2: Power output
[0055] P3: Power output power
[0056] PWM: Pulse Width Modulation Signal
[0057] RS: Resistor control signal
[0058] S100: Dynamic Power Control Process
[0059] S1: Detection signal
[0060] S2: Adjust signal
[0061] S3: Image signal
[0062] TS: Emitting source timing
[0063] VCC: Power supply terminal Detailed Implementation
[0064] This disclosure provides a light source driving device, including a power supply unit, a time-of-flight ranging module, and a signal processing unit. The power supply unit provides a power source. The time-of-flight ranging module is coupled to the power supply unit and includes a light source unit and a power detection unit. The light source unit has a light source output power. The power detection unit is coupled to the light source unit, stores a preset power, and detects the light source output power of the light source unit. The signal processing unit is coupled to the power supply unit and the time-of-flight ranging module, and receives a detection signal from the power detection unit. When the light source output power of the light source unit differs from the preset power, the signal processing unit transmits an adjustment signal to adjust the power supply output power of the power supply unit. Through the dynamically adjustable power time-of-flight ranging module design, the power detection unit can detect the light source output power of the light source unit, and then the power can be dynamically adjusted via feedback control to ensure the stability of the light source output power. Furthermore, when the detection distance of a sensed object is short, the light source output power can be dynamically reduced to achieve power saving.
[0065] The light source unit can be a VCSEL module or an edge-emitting laser (EEL) module; the power detection unit can be in voltage detection mode, current detection mode, or optical power detection mode; the memory can be an electrically erasable programmable read-only memory (EEPROM). The signal processing unit can use an integrated bus circuit (I-Integrated Circuit). 2 C) Communication signal transmission methods such as Serial Peripheral Interface (SPI) or Universal Asynchronous Receiver / Transmitter (UART), but this disclosure is not limited to these.
[0066] The error between the light source output power of the light source unit and the preset power is within ±1%; more preferably, the error between the light source output power of the light source unit and the preset power is within ±0.3%, but the present disclosure is not limited thereto.
[0067] The light source driver can detect the light source output power of the light source unit in real time and dynamically adjust the output power of the light source unit. Therefore, the time-of-flight ranging module can use a PCB of any length to connect to the power supply unit, avoiding the problem of unstable light source output power caused by voltage drop due to excessive circuit length or poor PCB manufacturing.
[0068] The time-of-flight ranging module also includes a time-of-flight sensor and a driving unit. The time-of-flight sensor receives reflected light from a target object and transmits an image signal to a signal processing unit. The driving unit is coupled to the time-of-flight sensor and the light source unit, and includes a driving chip and a transistor. The driving chip receives a transmission light source timing sequence from the time-of-flight sensor and converts the transmission light source timing sequence into an electrical signal. The transistor is coupled to the driving chip. The driving unit controls the transistor to turn on and off to control a signal duty cycle, thereby driving the light source unit to emit a high-frequency modulated laser. By controlling the duty cycle of the output signal of the driving unit, the function of dynamically adjusting the output power of the light source unit can be realized, thereby stabilizing the output power of the light source unit, or reducing the output power of the light source unit according to the distance to the target object to achieve power saving.
[0069] The time-of-flight sensor may be a CMOS image sensor (CIS), a single-photon avalanche diode (SPAD), an avalanche photodiode (APD), or a silicon photomultiplier (SiPM); the transistor 1242 may be a metal-oxide-semiconductor field-effect transistor (MOSFET), but this disclosure is not limited thereto.
[0070] The signal processing unit includes a digital signal processor (DSP) and a digital resistor chip. The DSP outputs a resistance control signal. The digital resistor chip is connected to the DSP and receives the resistance control signal to generate a corresponding resistance. By controlling the resistance value of the digital resistor chip, the power output power of the power supply unit can be dynamically adjusted.
[0071] The pull-up resistor can be a Zener diode or a pull-up transistor, but this disclosure is not limited to these.
[0072] The signal processing unit may further include a digital signal processor and a filtering circuit. The digital signal processor outputs a pulse width modulation (PWM) signal. The filtering circuit is connected to the digital signal processor and is used to suppress interference noise in the PWM signal. By dynamically outputting the PWM signal, the power supply output power of the power supply unit can be dynamically adjusted.
[0073] The filtering circuit is either an RC filter circuit or an LC filter circuit. The input terminal of the digital signal processor in the signal processing unit may also include an ADC to convert analog signals into digital signals for processing, and the output terminal of the digital signal processor may also include a DAC to convert the processed digital signal back into an analog signal for output. The digital signal processor can control power output by adjusting voltage or current, but this disclosure is not limited thereto. By setting up an RC or LC filter circuit, high-frequency noise can be eliminated, preventing interference with the control signals emitted by the digital signal processor.
[0074] The signal processing unit receives the image signal from the time-of-flight sensor and resets the preset power stored in the power detection unit according to the distance of the sensed object. When the image signal received by the signal processing unit indicates that the sensed object is close, a lower preset power is set to save the power consumption of the light source unit. Conversely, if the sensed object is far away, the preset power is increased to enhance the brightness of the light source unit and improve the accuracy of time-of-flight ranging.
[0075] The time-of-flight ranging module also includes a connection unit for connecting the power supply unit, signal processing unit, power detection unit, time-of-flight sensor, and drive unit. This eliminates the need to define additional pinouts for the connection unit on existing time-of-flight ranging modules; simply writing firmware to use different pinouts for data reading allows connection to existing I / O circuits. 2 The C-bus further reduces development costs.
[0076] This disclosure provides another light source driving device, which includes a power supply unit and a time-of-flight ranging module. The power supply unit provides a power source. The time-of-flight ranging module is coupled to the power supply unit and includes a light source unit, a power detection unit, and a power chip. The light source unit has a light source output power. The power detection unit is coupled to the light source unit to store a preset power and detect the light source unit's light source output power. The power chip is coupled to the power detection unit to receive the power from the power supply unit, adjust the power output power, and transmit the power output power to the light source unit. When the light source unit's light source output power differs from the preset power, the power chip adjusts the power output power. Therefore, by using the power chip on the time-of-flight ranging module, the power output power can be dynamically adjusted, making it compatible with more system-side modules (e.g., the power supply unit only outputs a fixed power, the power supply unit's output power is unstable, or the power supply unit's adjustable power range is too small). The system-side hardware does not need to be modified; only firmware needs to be written for dynamic power adjustment, avoiding increased costs due to module modifications.
[0077] The time-of-flight ranging module also includes a microcontroller unit. The microcontroller unit is coupled to a power detection unit and a power chip, and receives a detection signal from the power detection unit. When the output power of the light source unit differs from the preset power, the microcontroller unit sends an adjustment signal to control the power chip to adjust the power output power. By using the microcontroller unit, the system-side processing unit can be replaced, and the system-side hardware and firmware do not need to be modified, making it suitable for various types of system-side modules.
[0078] The microcontroller unit uses I 2 The C-bus reads signals from the power detection unit, but this disclosure is not limited thereto. By integrating the light source unit, power detection unit, power chip, and microcontroller unit into the time-of-flight ranging module, the light source output power of the light source unit can be dynamically adjusted more quickly.
[0079] The power supply unit is a fixed-power power module. The output power can be dynamically adjusted by the power chip installed in the time-of-flight ranging module, so existing fixed-power power modules can be used without modifying the system modules, thus reducing development costs.
[0080] This disclosure provides an electronic device that includes the aforementioned light source driving device.
[0081] The various technical features in the light source driving device disclosed above can be combined and configured to achieve corresponding effects. Based on the above embodiments, specific examples are provided below with detailed descriptions in conjunction with the accompanying drawings.
[0082] Please see Figure 1 and Figure 2 As shown, where Figure 1 A schematic diagram illustrating the light source driving device 100 according to the first embodiment of the present disclosure; and Figure 2 Drawing according to Figure 1 A schematic diagram of the dynamic power control process S100 of the light source driving device 100. In the first embodiment, the light source driving device 100 can be mounted on an electronic device such as a computer or mobile phone (not shown). The light source driving device 100 includes a system terminal 110 and a time-of-flight ranging module 120, with the time-of-flight ranging module 120 coupled to the system terminal 110. The system terminal 110 includes a power supply unit 111 and a signal processing unit 112. The time-of-flight ranging module 120 includes a light source unit 121, a power detection unit 122, a time-of-flight sensor 123, and a driving unit 124. The power supply unit 111 is coupled to the driving unit 124 of the time-of-flight ranging module 120, and the signal processing unit 112 is coupled to the power supply unit 111, the power detection unit 122 of the time-of-flight ranging module 120, and the time-of-flight sensor 123. The light source unit 121 is coupled to the power detection unit 122 and the driving unit 124. The power detection unit 122 is coupled to the time-of-flight sensor 123, and the time-of-flight sensor 123 is coupled to the driving unit 124. In the first embodiment, the light source unit 121 is a VCSEL module; the signal processing unit 112 uses I... 2 C is a communication signal transmission method.
[0083] Power supply unit 111 provides a power source (not shown separately). Light source unit 121 has a light source output power P1. Power detection unit 122 stores a preset power DP and detects the light source output power P1 of light source unit 121. Signal processing unit 112 receives a detection signal S1 from power detection unit 122. When the light source output power P1 of light source unit 121 is different from the preset power DP, signal processing unit 112 transmits an adjustment signal S2 to adjust the power supply output power P2 of power supply unit 111. It should be noted that an error between light source output power P1 and preset power DP greater than a preset range indicates that the two are different. In the first embodiment, the error between light source output power P1 of light source unit 121 and preset power DP is within ±1%.
[0084] like Figure 2As shown, the dynamic power control process S100 of the light source driving device 100 is as follows: First, a preset power DP is set and stored in the power detection unit 122. Next, the power detection unit 122 detects the light source output power P1 of the light source unit 121. Then, the signal processing unit 112 transmits the signal through I... 2 The detection signal S1 of C receives the light source output power P1 and compares it with the preset power DP (i.e., the error between the two is less than a preset range). When the preset power DP is not reached, the signal processing unit 112 transmits the adjustment signal S2 to control the power supply unit 111 to adjust the power supply output power P2. The power detection unit 122 will detect the light source output power P1 of the light source unit 121 again and compare the difference value again. This cycle is repeated until the light source output power P1 of the light source unit 121 is the same as the preset power DP (i.e., the error between the light source output power P1 and the preset power DP is less than ±1%).
[0085] In addition, the signal processing unit 112 can receive an image signal S3 from the time-of-flight sensor 123 and reset the preset power DP stored in the power detection unit 122 according to the distance of the sensed object.
[0086] In this way, the light source driving device 100 can detect the light source output power P1 of the light source unit 121 in real time and dynamically adjust the magnitude of the light source output power P1 to ensure the stability of the light source output power P1 of the light source unit 121. Furthermore, it can dynamically reduce the power when the detection distance of the sensing object is short to achieve the purpose of saving power.
[0087] Please see Figure 1 and Figure 3 As shown, where Figure 3 Drawing according to Figure 1 A schematic diagram of the power detection unit 122 in the first embodiment. The power detection unit 122 includes a power detection circuit 1221 and a memory 1222, with the power detection circuit 1221 coupled to the memory 1222. The power detection circuit 1221 is used to detect the light source output power P1 of the light source unit 121, and then connects the detected light source output power P1 and the preset power DP stored in the memory 1222 via I... 2 The detection signal S1 of the C bus is transmitted to the signal processing unit 112, which then compares the difference between the light source output power P1 and the preset power DP. In the first embodiment, the power detection circuit 1221 of the power detection unit 122 is in optical power detection mode; the memory 1222 is an EEPROM.
[0088] Please see Figure 1As shown, the time-of-flight sensor 123 is used to receive a reflected light from the object being sensed and to transmit an image signal S3 to the signal processing unit 112. In the first embodiment, the time-of-flight sensor 123 is a SPAD.
[0089] Please see Figure 1 and Figure 4 As shown, where Figure 4 Drawing according to Figure 1 A schematic diagram of the driving unit 124 in the first embodiment. The driving unit 124 is used to control the power supply of the input light source unit 121. The driving unit 124 includes a driving chip 1241 and a transistor 1242, with the transistor 1242 coupled to the driving chip 1241. The driving chip 1241 receives a light source emission timing TS from the time-of-flight sensor 123 and converts the light source emission timing TS into an electrical signal ES. The driving unit 124 controls the transistor 1242 to turn on and off, thereby controlling a signal duty cycle DC. In the first embodiment, the transistor 1242 is a MOSFET. It should be noted that the light source emission timing TS is an optical signal used to indicate whether the light source is turned on or off at a specific time, thereby encoding and transmitting information; when the driving unit 124 receives the light source emission timing TS from the time-of-flight sensor 123, it controls the signal duty cycle DC, and can then output a corresponding pulse width modulation signal PWM (illustrated in...). Figure 5B (Give light source unit 121.)
[0090] In detail, the driver chip 1241 receives the emission light source timing TS output by the time-of-flight sensor 123 and converts it into a single-point signal. Then, the transistor 1242 controls the signal duty cycle DC, thereby driving the light source unit 121 to emit a high-frequency modulated laser.
[0091] Please see Figure 1 and Figure 5A As shown, where Figure 5A Drawing according to Figure 1A schematic diagram of the signal processing unit 112a in the first embodiment of the first implementation. In the first embodiment of the first implementation, the signal processing unit 112a includes a digital signal processor (DSP) 1121, a digital resistor chip 1122, and a pull-up resistor 1123. The digital resistor chip 1122 is connected to the DSP 1121 and the pull-up resistor 1123. The digital resistor chip 1122 and the pull-up resistor 1123 are connected in series to a power supply terminal VCC. The DSP 1121 is used to output a resistance control signal RS. The digital resistor chip 1122 is used to receive the resistance control signal RS and generate a corresponding resistance. The DSP 1121 can dynamically adjust the power output power P2 of the power supply unit 111 by controlling the resistance of the digital resistor chip 1122. In the first embodiment of the first implementation, the pull-up resistor 1123 is a Zener diode.
[0092] In detail, the digital signal processor 1121 receives the detection signal S1 from the power detection unit 122 and the image signal S3 from the time-of-flight sensor 123, and compares the difference between the light source output power P1 and the preset power DP. When the preset power DP is not reached, the digital signal processor 1121 notifies the power supply unit 111 to adjust the power supply output power P2 by transmitting the adjustment signal S2. The digital signal processor 1121 outputs a resistance control signal RS to control the resistance value of the digital resistor chip 1122, thereby controlling the power output.
[0093] To further explain, the input terminal of the digital signal processor 1121 may include an analog-to-digital converter (ADC) (not shown) to convert analog signals into digital signals for processing, and the output terminal of the digital signal processor 1121 may include a digital-to-analog converter (DAC) (not shown) to convert the processed digital signals back into analog signals for output.
[0094] Therefore, when the image signal S3 received by the digital signal processor 1121 shows that the distance to the sensed object is relatively close, it can output an adjustment signal S2 to reduce the power, thereby saving the power consumption of the light source unit 121.
[0095] Please see Figure 1 and Figure 5B As shown, where Figure 5B Drawing according to Figure 1A schematic diagram of the signal processing unit 112b in the second embodiment of the first embodiment. In the second embodiment of the first embodiment, the signal processing unit 112b includes a digital signal processor 1121, a filter circuit 1124, and a voltage divider resistor 1125. The filter circuit 1124 is connected to the digital signal processor 1121 and the voltage divider resistor 1125. The filter circuit 1124 and the voltage divider resistor 1125 are connected in series to a power supply terminal VCC. The voltage divider resistor 1125 is connected to a ground terminal GND.
[0096] The digital signal processor 1121 outputs a pulse width modulation (PWM) signal to dynamically adjust the power output P2 of the power supply unit 111. The filter circuit 1124 is used to suppress interference noise of the PWM signal. In the second embodiment of the first implementation, the filter circuit 1124 is an RC filter circuit.
[0097] Please see Figure 1 As shown, the light source driving device 100 may further include a connection unit 125, which is used to connect the power supply unit 111, the signal processing unit 112, the power detection unit 122, the time-of-flight sensor 123 and the driving unit 124.
[0098] Please see Figure 6 As shown, Figure 6 A schematic diagram of the light source driving device 200 according to the second embodiment of this disclosure is shown. In the second embodiment, the light source driving device 200 also includes... Figure 1 The second embodiment of the light source driving device 200 comprises a power supply unit 111, a signal processing unit 112, a light source unit 121, a power detection unit 122, a time-of-flight sensor 123, a driving unit 124, and a connection unit 125. The difference between the second embodiment and the first embodiment lies in the fact that the time-of-flight ranging module 120 of the light source driving device 200 also includes a power chip 126, the connection relationship between the power supply unit 111 and the signal processing unit 112 and the driving unit 124, and the power supply unit 111 is a fixed-power power module. Specifically, the power chip 126 is coupled to the power supply unit 111, the power detection unit 122, the driving unit 124, and the connection unit 125. The power supply unit 111 is not coupled to the signal processing unit 112 and the driving unit 124, and the power supply output power P2 of the power supply unit 111 is a constant power.
[0099] The power chip 126 receives power from the power supply unit 111 and adjusts the power output power P3, then transmits the power output power P3 to the light source unit 121 via the drive unit 124. When the light source output power P1 of the light source unit 121 is different from the preset power DP, the power chip 126 adjusts the power output power P3. Specifically, the signal processing unit 112 can first... 2The C-bus connects to the connection unit 125 to read the detection signal S1 from the power detection unit 122, and then sends the adjustment signal S2 to the power chip 126. The power chip 126 then uses I-bus to... 2 After receiving the adjustment signal S2, the C bus will adjust the constant power supply input by the power supply unit 111, and then dynamically adjust the power output P3 output to the drive unit 124.
[0100] Please see Figure 7 As shown, Figure 7 A schematic diagram of the light source driving device 300 according to the third embodiment of this disclosure is shown. In the third embodiment, the light source driving device 300 also includes... Figure 6 The light source driving device 300 of the third embodiment comprises a power supply unit 111, a signal processing unit 112, a light source unit 121, a power detection unit 122, a time-of-flight sensor 123, a driving unit 124, a connection unit 125, and a power chip 126. The difference between the light source driving device 300 of the third embodiment and the light source driving device 200 of the second embodiment is that the time-of-flight ranging module 120 of the light source driving device 300 also includes a microcontroller unit 127. Specifically, the microcontroller unit 127 is coupled to the power detection unit 122 and the power chip 126.
[0101] The microcontroller unit 127 is used to receive the detection signal S1 from the power detection unit 122. The microcontroller unit 127 can be controlled via I... 2 The C-bus reads the detection signal S1 from the power detection unit 122, and the microcontroller unit 127 controls the power chip 126 to dynamically adjust the power. When the light source output power P1 of the light source unit 121 is different from the preset power DP, the microcontroller unit 127 sends an adjustment signal S2 to control the power chip 126 to adjust the power output power P3. Specifically, the microcontroller unit 127 can integrate the dynamic power control from the system terminal 110 onto the time-of-flight ranging module 120. In the third embodiment, the microcontroller unit 127 is a microcontroller (MCU).
[0102] Although the present disclosure has been described above with reference to embodiments, it is not intended to limit the present disclosure. Any person skilled in the art may make various modifications and alterations without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be determined by the appended claims.