Generally speaking, the weakening of high-power LED exists in the beginning. Factories like ours all hope to buy LED materials with steady performance, so the aging is necessary to LED. There are several kinds of ways of aging, such as conventional aging, pulsed current shock experiments, and so on.
There are several ways to achieve the conventional aging
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Series connection: under the circumstance of constant voltage and current
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Parallel connection aging
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Series-parallel connection aging: under the circumstance of constant voltage and current
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Single LED chip aging under constant current
Comparing the 4 kinds of methods with each other, the first and the third one are the same that if there is something wrong with one of the LED chips, all chips will be influenced, such as the short circuit or the broken circuit, however, the second one is opposite, every LED chip has nothing to do with any other one, so the aging is unaffected; in fact, current-limiting via resistor is also not reliable, because the parameter of LED will be greatly affected by both the shift rate of resistor and the voltage change. Obviously, the fourth is the most scientific one, for it’s to conform to the character of LED current.
Aging is an significant process in the equipment, while it’s always neglected by most manufacturers. If there is something wrong with the aging, then parameters analysis will be affected, including the brightness, wavelength, and so on. Pulsed current shock experiment is usually used for aging, and the constant current source is used, of which the frequency and current is adjustable, so the quality and the expectant life span of LED could be judged in a short time.