Before talking about the causes of light decay of 1209 SMD LED lamp beads, we must first know what light decay is. Light decay generally refers to its lumen value. Accumulation, the potential also continues to rise, and finally the "saturation state" potential is achieved, which is the maximum potential. The surface potential will decrease with the change of time. Generally, the potential during operation is less than this potential. The whole process of this potential decreasing with time is called the whole process of "dark decay". When the photosensitive drum is exposed by the scanner, the potential of the shadow (referring to the part of the photoconductor surface that is not directly exposed to light) is still in the whole process of dark decay; the light area (referring to the part of the photoconductor surface that is directly exposed to light) The relative density of free electrons in the light guide layer is fast. When it is increased, the conductivity increases rapidly, the light-guiding working voltage is generated, the positive charge fades rapidly, and the surface potential of the photoconductor also decreases sharply.

LED lamp beads are getting darker and darker, which is a very common situation. There are many reasons why the LED lamp beads can be dimmed, and then we will talk about them in detail.

Controller damage: 1209LED lamp beads are required to work in DC low voltage (below 20V), but our usual voltage is AC high voltage (communication AC 220V). To turn the voltage into the electricity necessary for the lamp beads, a device is necessary, called "LED constant current power supply led driver". Theoretically speaking, as long as the main parameters of the controller are consistent with the lamp bead board, the power supply system can be continuously supplied, and everything can be used normally. The inside of the controller is more complicated. Any common failure of a device (such as capacitors and electronic rectifiers) is likely to cause changes in the output voltage, resulting in dim lighting. Controller damage is one of the most common common faults in LED lamps. Generally, it can be dealt with after the controller is replaced.

LED damage: The LED itself is composed of lamp beads one by one. If one or part of them does not light up, it will definitely cause all lighting fixtures to be dimmed. Lamp beads are generally connected in series first and then in series - so if a certain lamp bead is damaged, it is very likely that a batch of lamp beads will not light up. There are obvious small black spots on the surface of the damaged lamp bead, look for it, connect a cable to its reverse side, and short-circuit it; or replace it with a new lamp bead, all of which can solve the problem. LEDs sometimes break one, probably by coincidence. If it is often damaged, the controller problem should be considered - another main manifestation of the common failure of the controller is damage to the lamp beads.

LED light decay: To put it bluntly, light decay is a sharp drop in the chromaticity of the luminous object - these conditions are more pronounced on fluorescent lamps and fluorescent tubes. LED lights can also prevent light decay, but its light decay rate is very slow, and it is generally difficult to see the change with the human eye. However, they do not remove fake and inferior LEDs, or fake and inferior bead boards, or due to various factors such as poor heat removal, resulting in faster LED light decay rate.

LED light flickering: In the process of charging the capacitor battery, the light is flickering - because the internal current of the capacitor is small, the battery charging rate is relatively slow, so you can still see the light goes out with your eyes. When the capacitor is flooded with electricity, it releases electromagnetic energy at one time, which illuminates the lamp. But with less electromagnetic energy being stored, the light will soon go out - with continuous battery charging, charging and discharging, all the human eye sees is the light flickering. When the light is in normal use, no flickering is visible, because the current amount of the capacitor is relatively large, and the battery charging rate is very fast.