Encounter LED dead light phenomenon
1) LED leakage current is too large cause PN junction failure, so that led light is not bright, this situation generally does not affect the work of other LED lights
2) LED internal connection lead disconnect, resulting in LED current through the dead lamp, this situation will affect the normal operation of other LED lights.
To this end, how should we prevent the LED dead light? According to Chao Yi electronics business lighting department researchers found that static electricity on the LED lights is a great harm to the devil, the world because of electrostatic damage to electronic components countless, resulting in tens of millions of dollars in economic losses. So to prevent static damage to electronic components, the electronics industry is a very important work, LED packaging, the application of enterprises do not take it lightly. Any part of the problem, will cause damage to the LED, LED performance deterioration or even failure. We know that the human body (ESD) static can reach about three thousand volts, enough to break the LED chip breakdown, in the LED packaging production line, all kinds of equipment, grounding resistance is in line with the requirements, which is very important, generally require grounding resistance of 4 Ohm, some demanding high ground resistance even to achieve ≤ 2 ohms.
The human body static damage to the LED is also great, work should wear anti-static clothing, with static ring, static ring should be well grounded, there is no need to ground the static ring static effect is not good, it is recommended not to use with The product, if the staff in violation of operating procedures, should receive the appropriate warning education, but also play a role in informing others. How much of the body with static electricity, and people wear different fabric clothes, and their physical and related, autumn and winter night we underestimate the clothes is easy to see the discharge between the phenomenon, this electrostatic discharge voltage there are three thousand volts.
Some enterprises use manual welding, the use of 40-watt ordinary soldering iron, welding temperature can not control the soldering iron temperature above 300-400 ℃, too high welding temperature will cause dead lights, LED lead at high temperature expansion coefficient than at 150 ℃ or so The expansion coefficient is several times higher, the internal gold solder joints will be too large because of the thermal expansion and contraction will be opened, resulting in the phenomenon of dead lights.
In view of the above phenomenon, we recommend LED packaging manufacturers and LED lighting application manufacturers should develop a strict standard LED manual, in the production process to prevent the occurrence of on-line phenomenon