In the face of global energy shortage and environmental pollution, LED display screens have broad application space due to their energy saving and environmental protection characteristics. The application of LED lighting products in the lighting field is attracting the attention of the world. Generally speaking, the stability and quality of LED lamps are closely related to the heat dissipation of the lamp itself. Currently, the heat dissipation of high-brightness LED lamps on the market often uses natural heat dissipation, and the effect is not ideal. LED lamps made from LED light sources are composed of LEDs, heat dissipation structures, drivers, and lenses, so heat dissipation is also an important part. If the LED cannot dissipate heat well, its lifespan will also be affected.
The effect of heat on high-brightness LEDs
Heat is concentrated in a chip with a very small size, and the chip temperature increases, causing non-uniform distribution of thermal stress, chip luminous efficiency and phosphor lasing efficiency decreasing; when the temperature exceeds a certain value, the device failure rate increases exponentially. Statistics show that for every 2°C increase in component temperature, reliability drops by 10%. When multiple LEDs are densely arranged to form a white light lighting system, the heat dissipation problem is more serious. Solving thermal management issues has become a prerequisite for high-brightness LED applications.
The relationship between chip size and heat dissipation
The most direct way to improve the brightness of a power LED display is to increase the input power. In order to prevent saturation of the active layer, the size of the p-n junction must be increased accordingly; increasing the input power will inevitably increase the junction temperature, thereby reducing the quantum efficiency. reduce. The increase in single-tube power depends on the device's ability to dissipate heat from the p-n junction. While maintaining the existing chip materials, structure, packaging process, unchanged current density on the chip, and equivalent heat dissipation conditions, the size of the chip and the junction area are increased separately. Temperatures will continue to rise.
