Thermal flipping for prolonged life of light source controller circuits
By employing a thermal flip algorithm in lighting equipment and using temperature sensors to adjust LED dimming, the impact of overheating of the light source on electronic components is resolved, achieving temperature control of the lighting equipment. This solves the temperature control problem that has not been addressed in existing technologies and achieves a satisfactory temperature control effect for the lighting equipment.
Patent Information
- Application Number
- CN202480049392.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-07-26
- Filing Date
- 2024-07-25
- Publication Date
- 2026-02-24
AI Technical Summary
Overheating caused by light sources in lighting equipment can adversely affect the lifespan of critical electronic components, and existing technologies struggle to effectively control temperature to extend equipment lifespan.
A thermal flip algorithm is adopted, which uses a temperature sensor to detect the temperature of the electronic board and adjusts the dimming percentage of the LED module to control the temperature of the electronic board within a safe limit and reduce the brightness of the light source to reduce the impact of overheating.
Effectively maintain the temperature of key electronic components within a safe range, reduce equipment degradation, and extend the lifespan of the light source controller circuit.
Smart Images
Figure CN121569588A_ABST
Abstract
Description
Background Technology
[0001] Lighting equipment includes one or more light sources, such as light-emitting diodes (LEDs), and associated components for operating the one or more light sources within its housing. Some lighting equipment has an enclosed housing for the one or more light sources, for example in the form of a molded window, which can provide protection in a variety of environments, including hazardous environments. However, enclosing the light source within the lighting equipment can cause the temperature inside the housing to rise to levels that adversely affect the lifespan of critical electronic components, such as controllers and memory.
[0002] These heating effects can cause LED-based light sources to dim over time, as well as reliability issues and potential premature failure of lighting equipment. Summary of the Invention
[0003] Techniques for extending the lifespan of light source controller circuits are described.
[0004] In some aspects, the technology described herein relates to a lighting device comprising: an LED module; a dimming control circuit located on an electronic board, the dimming control circuit adjusting the dimming of the LED module; a temperature sensor located on the electronic board; and a controller having a memory storing instructions for a thermal flip algorithm that controls the dimming control circuit to maintain the temperature of the electronic board within safe limits based on the temperature of the electronic board detected by the temperature sensor.
[0005] In some aspects, the technology described herein relates to a method for controlling the temperature of a control circuit of a lighting device, the method comprising: adjusting the dimming of an LED module based on the temperature of an electronic board on which the control circuit is mounted.
[0006] This summary is provided to introduce, in a simplified form, the selection of concepts further described in the detailed embodiments below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. Attached Figure Description
[0007] Figures 1A to 1D A view of an example lighting device is shown.
[0008] Figure 2 An example method for extending the lifespan of a light source controller circuit is shown.
[0009] Figure 3A and Figure 3B The hot flip algorithm and its corresponding state machine diagrams are shown respectively.
[0010] Figure 4A schematic diagram of a controller for implementing a method for extending the lifetime of a light source controller circuit is shown, such as... Figure 3A The hot flipping algorithm.
[0011] Figure 5 The graph shows the temperature versus dimming details of the BL653 module in the example implementation. Detailed Implementation
[0012] Techniques for extending the lifespan of light source controller circuits are described. A thermal flip-flop algorithm is proposed to protect the light source controller mounted on the electronic board from overheating caused by the light source.
[0013] The thermal switching algorithm controls the LED temperature by modulating the LED's dimming (based on the temperature read from a temperature sensor), and thus controls the temperature of critical electronic components, keeping the temperature within safe limits for these components. Advantageously, a suitable circuit temperature can be maintained because temperature regulation does not rely on optimizing the LED temperature. Within the temperature range of the lighting equipment, the temperature is detected at or near the critical electronic components.
[0014] Figures 1A to 1D A view of an example lighting device is shown. Figure 1A A representative schematic diagram of a lighting device with an extended lifespan featuring a light source controller circuit is shown. Figure 1B An example housing 105 for a lighting device 100 is shown. Figure 1C An internal view of example housing 105 is shown. Figure 1D The LED package 115 and electronic board 130 that can be used in the housing 105 are shown.
[0015] refer to Figure 1A The lighting device 100 includes: an LED module 110; a dimming control circuit 120 located on an electronic board 130; a temperature sensor 140 located on the electronic board 130; and a controller 150 having a memory storing instructions for a thermal flip algorithm that controls the dimming control circuit 120 to maintain the temperature of the electronic board 130 within safe limits based on the temperature detected by the temperature sensor 140. The dimming control circuit 120 adjusts the dimming of the LED module 110.
[0016] refer to Figure 1B and Figure 1C The housing 105 of the lighting device 100A may enclose the LED package 115 and the circuitry for controlling the LED module, for example, located behind the molded window 108.
[0017] refer to Figure 1DIn the example implementation, the electronic board 130 is disposed within the housing 105 and connected to the LED package 115 via spacer 160, and electrically coupled using connectors 170 and wires 180 from the power board (not shown) and the controller subassembly (not shown). The controller circuitry (including dimming control circuitry (not shown) and a controller (not shown) with a memory storing a hot-flip algorithm) (see example...) Figure 4 The controller 400 and the temperature sensor 140 are mounted on the electronic board 130.
[0018] The controller circuitry (e.g., controller 150) on the electronic board 130 degrades at high temperatures, affecting the lifespan of the device. Therefore, when executing the hot-flip algorithm, the controller controls the dimming control circuitry to maintain the temperature of the electronic board 130 within safe limits based on the temperature of the electronic board 130 detected by the temperature sensor 140.
[0019] Figure 2 An example method for extending the lifespan of a light source controller circuit is shown. A method for controlling the temperature of a control circuit in a lighting device includes adjusting the dimming of an LED module based on the temperature of an electronic board on which the control circuit is mounted. For example, method 200 includes receiving (210) temperature information from a temperature sensor that detects the temperature near the control circuit. Then, based on the detected temperature, method 200 includes determining (220) that the temperature of the control circuit is higher than a first threshold based on the received temperature information; outputting (230) a control signal to a dimming control circuit to adjust the dimming percentage; and guiding (240) the dimming control circuit to further gradually adjust the dimming percentage when the received temperature information indicates that the temperature of the control circuit is higher than a second threshold lower than the first threshold. The method may further include allowing (250) the dimming percentage to return to a higher dimming percentage after the received temperature information indicates that the temperature of the control circuit is at or below the second threshold. The control signal is output based on a thermal reversal algorithm.
[0020] For example, as part of a thermal reversal algorithm, when the temperature detected by a temperature sensor is greater than a first threshold, the method includes: outputting a control signal to a dimming control circuit to begin reducing the dimming percentage by a first number of points every first time interval until the temperature reaches a second threshold, which is a temperature lower than the first threshold; and when the temperature detected by the temperature sensor is equal to or lower than the second threshold, the method includes: outputting a control signal to the dimming control circuit to begin returning the dimming percentage to a second number of points every second time interval. The first number of points may be equal to the second number of points or a different number of points (e.g., the first number of points may be 10 points and the second number of points may be 5 points). The first time interval may be equal to the second time interval or a different amount of time (e.g., the first time interval is 20 minutes and the second time interval is 10 minutes).
[0021] When the temperature is greater than a first threshold and when the temperature is greater than a third threshold, the method can also limit the maximum dimming percentage to a reduced maximum dimming percentage. The third threshold is a temperature lower than the second threshold. In some cases, when the temperature detected by the temperature sensor is greater than the first threshold, the current dimming percentage is reduced to the reduced maximum dimming percentage before starting to reduce the dimming percentage by a first point.
[0022] The thermal flip algorithm reduces the brightness of the light source through adaptive dimming to offset the ambient temperature exposed to the lighting equipment. Therefore, the internal temperature within the equipment is tracked, and brightness is reduced via adaptive dimming to control the internal temperature. This temperature control aims to reduce the degradation of the light source controller.
[0023] Figure 3A and Figure 3B The hot-flip algorithm and its corresponding state machine diagrams are shown below. (Reference) Figure 3A and Figure 3B The system's default state after power-on is "On". During an initial period (e.g., 1 minute), the state changes between "On" and "Idle", and the system waits for a new dimming command. Once the initial period has elapsed, the state changes from "On" to "On". The "On" state is based on temperature information received by a temperature sensor (e.g., ...). Figure 3A The "reading of the electronic board temperature" is converted into normal state, active state, recovery state, and end state. The specific implementation is described below. It should be noted that the specific increments presented for adjusting dimming and time periods are only one implementation. Furthermore, the temperature threshold may also vary depending on the expected lifespan extension of the specific circuit component / memory.
[0024] When the temperature exceeds 95°C, the status is updated to "Action". In this state, the thermal flip activity flag is set and the reset flag is reset. The action here is to reduce the dimming by 10 points. Once the temperature is above 95°C and the dimming exceeds 70%, the dimming is set to 70%, and every 20 minutes, the dimming is gradually reduced by 10 points until the temperature reaches 90°C.
[0025] When the temperature is above 90°C but below 95°C, check the thermal flip activity flag. If the activity flag is set, the status is updated to "Action". The action here is to decrease the dimming by 10 points. If the thermal flip activity flag is not set, check if the thermal flip reset flag is set. If the thermal flip reset flag is set, the status is updated to "Reset". The action here is to increase the dimming by 10 points.
[0026] If the temperature is greater than or equal to 85°C and less than or equal to 90°C, the status will be updated to recovery. The thermal reversal recovery flag will be set and the activity flag reset. The current dimming will be gradually reduced by 10 points every 20 minutes. It should be noted that dimming with a current greater than the required level will not be applied until the temperature reaches below 85°C.
[0027] If the temperature is below 85°C, the status is updated to normal. At this time, any dimming percentage in the range of 0% to 100% is applicable.
[0028] If none of the above conditions are met, it may mean that the memory is corrupted. The action here is to restart the algorithm ("update the state to end", and then restart the algorithm to start from the beginning again).
[0029] like Figure 3B As shown, the thermal toggle flag is set after every minute. Idle, Active, Normal, Recover, and Timeout states set the dimming. In the Active state, the thermal toggle flag and temperature are checked in the thread context to delegate work. In the Active state, dimming decreases. In the Recover state, dimming recovers. The Timeout state limits the LED driver from dimming to entering a safe mode by applying current.
[0030] The internal temperature of the device is tracked by sensing the temperature of the electronic board (e.g., Figure 3A (e.g., "reading the temperature of the electronic board"). For example, a thermal sensor is connected to / mounted on an electronic board (on which the controller is also mounted). The data captured by the thermal sensor is read from the sensor IC via the I2C protocol (but may be another protocol), and then used by an algorithm on the controller, which subsequently sends control signals (in digital format) to the driver, for example, via the UART protocol.
[0031] It should be understood that, during the operation of the described thermal flip algorithm, other temperature sensors and dimming control algorithms may be included for other purposes.
[0032] Figure 4 A schematic diagram of a controller for implementing a method for extending the lifetime of a light source controller circuit is shown, such as... Figure 3A The hot flipping algorithm. (Reference) Figure 4 The controller 400 may include: a processor 410; a memory 420; and input / output circuitry 430, which can communicate via a bus 440 (which may be on-chip or between chips, depending on the implementation). The processor can be any suitable processing unit and may include information about... Figure 3BThe state machine 350 is described. Memory 420 may include, but is not limited to, random access memory (RAM), such as static random access memory (SRAM) and dynamic random access memory (DRAM), flash memory, and magnetic memory. Memory 420 stores data and instructions for various operations of the controller 400, including those for... Figure 2 Method 200 and Figure 3A The instructions for algorithm 300. Input / output circuitry 430 may include signal interfaces suitable for communicating with other components on the electronic board (e.g., for receiving input from a temperature sensor on the electronic board and for outputting control signals to a driver). Input / output circuitry 430 may include wireless interfaces and circuitry such as those for Bluetooth or Near Field Communication (NFC) protocols.
[0033] Example Operation
[0034] The operation of the thermal flip algorithm was tested in a hot oven using a BL653 (Nordic NRF52833 controller) and a temperature sensor. The oven temperature was set at 65°C. For the thermal flip algorithm, the upper temperature threshold was set at 95°C and the lower temperature threshold was set at 90°C.
[0035] Figure 5 The graph shows the temperature versus dimming details of the BL653 module in the example implementation. During testing, the software recorded the temperature change and dimming percentage every 4 seconds. (Reference) Figure 5 It can be seen that once the temperature exceeds 95°C and the dimming exceeds 70%, the dimming is set to 70%, and every 20 minutes, the dimming is gradually reduced by 10 points until the temperature reaches 90°C. Furthermore, when the temperature decreases to a range below 90°C but above 85°C, the current dimming is gradually reduced by 10 points every 20 minutes. It should be noted that dimming with current exceeding the limit will not be applied until the temperature reaches below 85°C.
[0036] Although this subject matter has been described in language specific to structural features and / or actions, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as examples of implementing the claims, and other equivalent features and actions are intended to be within the scope of the claims.
Claims
1. A lighting device, comprising: LED module; A dimming control circuit, located on the electronic board, adjusts the dimming of the LED module; A temperature sensor is located on the electronic board; as well as The controller has a memory that stores instructions for a hot-flip algorithm that controls the dimming control circuit to maintain the temperature of the electronic board within safe limits based on the temperature of the electronic board detected by the temperature sensor.
2. The lighting device according to claim 1, wherein, The controller includes a state machine.
3. The lighting device according to claim 1, wherein, The controller and the dimming control circuit are mounted together on the electronic board.
4. The lighting device according to claim 1, wherein, The instructions for the hot-flip algorithm guide the controller to perform the following operations: When the temperature detected by the temperature sensor is greater than a first threshold, a control signal is output to the dimming control circuit to begin reducing the dimming percentage by a first number of points every first time interval until the temperature reaches a second threshold, which is a temperature lower than the first threshold; and When the temperature detected by the temperature sensor is equal to or lower than the second threshold, a control signal is output to the dimming control circuit to start returning the dimming percentage to the second point every second time interval.
5. The lighting device according to claim 4, wherein, The instructions for the hot-flip algorithm also instruct the controller to perform the following operations: When the temperature is greater than the first threshold and at the same time the temperature is greater than the third threshold, the maximum dimming percentage is limited to a reduced maximum dimming percentage.
6. The lighting device according to claim 5, wherein, The third threshold is a temperature lower than the second threshold.
7. The lighting device according to claim 5, wherein, The instructions for the hot-flipping algorithm also instruct the controller to reduce the current dimming percentage to the reduced maximum dimming percentage before starting to reduce the dimming percentage by the first number of points when the temperature detected by the temperature sensor is greater than the first threshold.
8. The lighting device according to claim 4, wherein, The first number is equal to the second number.
9. The lighting device according to claim 4, wherein, The first time period is equal to the second time period.
10. A method for controlling the temperature of a control circuit for a lighting device, the method comprising: The dimming of the LED module is adjusted based on the temperature of the electronic board with the control circuitry installed.
11. The method according to claim 10, wherein, Adjusting the dimming of LED modules based on the temperature of an electronic board equipped with control circuitry includes: Temperature information is received from a temperature sensor, which detects the temperature of the electronic board on which the control circuit is installed; Based on the received temperature information, it is determined that the temperature of the control circuit is higher than a first threshold. Output a control signal to the dimming control circuit to adjust the dimming percentage; and When the received temperature information indicates that the temperature of the control circuit is higher than the second threshold, the dimming control circuit is guided to further gradually adjust the dimming percentage.
12. The method according to claim 11, wherein, Outputting the control signal to the dimming control circuit to adjust the dimming percentage; and when the received temperature information indicates that the temperature of the control circuit is higher than the second threshold, guiding the dimming control circuit to further gradually adjust the dimming percentage includes: A control signal is output to the dimming control circuit to begin reducing the dimming percentage by a first number of points every first time interval until the temperature reaches a second threshold, the second threshold being a temperature lower than the first threshold.
13. The method of claim 12, further comprising: When the temperature is greater than the first threshold and at the same time the temperature is greater than the third threshold, the maximum dimming percentage is limited.
14. The method of claim 11, further comprising: After the received temperature information indicates that the temperature of the control circuit is at or below the second threshold, the dimming percentage is allowed to return to a higher dimming percentage.
15. The method according to claim 14, wherein, Allowing the dimming percentage to return to the higher dimming percentage after the received temperature information indicates that the temperature of the control circuit is at or below the second threshold includes: A control signal is output to the dimming control circuit to begin returning the dimming percentage to a second point every second time interval.