Multi-junction LED Thermal Protection via Voltage-Based Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional LED thermal protection structures are inadequate for multi-junction LED lighting modules, leading to inaccurate temperature detection and delayed cooling of overheated devices, which can result in performance degradation and premature failure of the central LED die.
Innovation Solution
A feedback mechanism is implemented to actively monitor and adjust the electrical current of the central LED die, which is likely to be the hottest due to blocked heat dissipation, using a substrate with a printed circuit board (PCB) and heat sink for effective thermal management, and employing operational amplifiers (Op-Amps) and analog-to-digital converters to sense temperature changes and reduce current flow when thresholds are exceeded.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional thermal protection structures are used in multi-junction LED modules, then the structure is simple, but temperature detection accuracy is poor and overheating prevention is delayed
Solution Approach 1:
The patent implements a feedback mechanism where temperature sensors continuously monitor the central LED die temperature, and the system automatically adjusts electrical current based on detected temperature changes. This closed-loop feedback system resolves the contradiction by providing accurate real-time temperature detection that triggers timely protective actions, overcoming the limitations of traditional open-loop thermal protection.
Solution Approach 2:
The patent replaces traditional mechanical or passive thermal protection mechanisms with an electronic sensing and control system. Operational amplifiers and analog-to-digital converters are used to detect temperature changes and convert them into control signals for current adjustment, substituting mechanical thermal management with electronic intelligence to achieve higher detection accuracy.
2Reliability
If the central LED die is surrounded by other LED devices, then heat dissipation is blocked causing the central die to be hotter, but traditional protection structures cannot detect and respond to this localized overheating
Solution Approach 1:
The patent divides the thermal protection function into localized segments by placing individual temperature sensors on specific LED dies, particularly the central die that is most susceptible to overheating. This segmentation allows independent monitoring and control of each LED die's temperature, enabling targeted protection without affecting the entire module.
Solution Approach 2:
The patent implements preliminary protective action by continuously monitoring LED die temperatures and automatically reducing electrical current to the central LED die before catastrophic failure occurs. The system proactively responds to temperature increases by adjusting current in real-time, preventing the conditions that would lead to device failure rather than reacting after failure has occurred.
3Measurement precision
If feedback mechanism with operational amplifiers and analog-to-digital converters is implemented, then temperature detection accuracy improves and timely cooling is achieved, but device complexity increases
Solution Approach 1:
The patent employs operational amplifiers that serve multiple functions: they amplify weak temperature sensor signals, compare detected temperatures against reference thresholds, and generate appropriate control signals for current reduction. This multi-functionality reduces the need for separate dedicated components for each function, thereby limiting the increase in overall device complexity while maintaining high detection accuracy.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution ensures timely cooling of the central LED die, preventing overheating and extending its lifespan, while maintaining the performance and reliability of the LED module.
Implementation Method 1
a substrate with a printed circuit board (PCB) and heat sink for effective thermal management
Implementation Method 2
heat sink for effective thermal management
Implementation Method 3
employing operational amplifiers (Op-Amps) and analog-to-digital converters to sense temperature changes
Data Source
AI summary
A system includes a plurality of light-emitting devices electrically coupled together. A temperature of each of the light-emitting devices is correlated with a voltage of said light-emitting device. The system includes a current driver configured to control an amount of current through at least a subset of the light-emitting devices. The system includes electronic circuitry that is electrically coupled to the subset of the light-emitting devices. The electronic circuitry is configured to: measure a voltage of the subset of the light-emitting devices while the light-emitting devices are in operation; determine, based on the measured voltage, whether the subset of the light-emitting devices is hotter than an acceptable temperature threshold; and instruct the current driver to reduce the amount of current through the subset of the light-emitting devices if the subset of the light-emitting devices has been determined to be hotter than the acceptable temperature threshold.