One, 0603 SMD LED lamp bead light decay is an irreversible brightness decay phenomenon caused by damage to the light source material.
The light decay of 0603 SMD LED lamp beads means that the light intensity of the LED lamp beads will be lower than the original light intensity after a period of time. The lower part is the light decay of 0603 SMD LED lamp beads. my country has not yet The luminous decay standard of 0603 SMD LED lamps is formulated. The industry stipulates that the luminous flux maintenance rate of 50,000 hours is greater than 70%, which is considered invalid.
Second, the decrease of luminous flux does not mean the luminous decay.
After 0603 SMD LED lamp beads work, their light intensity will decrease as the junction temperature of the chip increases, and the light efficiency will decrease accordingly. This is the inherent physical characteristic of semiconductors that change with temperature. As long as a certain part of the LED lamp bead light source does not exceed Damaged by the temperature limit, 0603 SMD LED lamp beads will not be used. After the temperature is restored for a period of time, the light intensity will return to the initial value. That is to say, no matter how long the 0603 SMD LED lamp has been working, as long as the initial light intensity remains the same It can’t be regarded as light decay. The light decay of 0603 SMD LED lamp bead refers to the failure phenomenon of LED lamp bead light source that no longer recovers due to a certain material damage. 0603 SMD LED lamp bead light source does not damage the luminous flux and has The ratio of loss of luminous flux.
Three, the main reason for the light decay of the 0603 SMD LED lamp bead light source is the insufficient temperature resistance of the colloid.
Chips and other materials are inorganic materials. Experiments have shown that chips and phosphors are not a problem in principle. From the perspective of the light source system, the main reason for the bead decay of 0603 SMD LED lamps is the insufficient temperature resistance of the colloid and high power. The best encapsulant for LED lamp beads can withstand a temperature of only more than 100 degrees. Tests have proved that a 50W integrated light source is often as high as 200 degrees when working with a large enough radiator, whether it is potting glue or PPA for a long period of time. High temperature operation will inevitably cause colloidal cracks, carbonization, separation from the chip and cause light decay.
From the perspective of the lighting system, the LED lamp bead decay is related to the thermal resistance of the system, including heat dissipation channels, heat dissipation materials, heat dissipation methods, and temperature-related components, etc.
The light decay of 0603 SMD LED lamp bead light source is determined by the support structure, chip, phosphor quality, colloid temperature resistance performance, packaging process factory and other conditions. The first choice is the weather resistance of the packaging support and colloid. In a sense, straight The core technology of plug-in LED lamp bead packaging should be the research and development and manufacturing technology of the package bracket, which determines the purpose, function and cost-effectiveness of the 0603 SMD LED lamp bead light source.
