Some companies increase profits in order to reduce costs. Use inferior drivers. Let the explosion-proof products that should be safe have unsatisfactory safety problems. In order to reduce the cost of products, some manufacturers use constant voltage to drive LEDs, which also brings a series of problems such as uneven brightness of each LED and the inability of LEDs to work in good condition during mass production. Countersink Neodymium Plate/Block Magnets Ningbo Hope Magnet Co.,Ltd , https://www.nbhopemagnet.com
The constant current source drive is a good LED driving method. It is driven by a constant current source without using a current limiting resistor in series with the output circuit. The current flowing through the LED is also not affected by changes in external power supply voltage, ambient temperature changes, and discrete LED parameters. Therefore, the current can be kept constant, and the various excellent characteristics of the LED can be fully utilized.
The LED constant current power supply is used to supply power to the LED lamps. Since the current flowing through the LED is automatically detected and controlled during the power supply operation, there is no need to worry about excessive current flowing through the LED at the moment of power-on, and there is no need to worry about load short-circuit burning Bad power supply.
Adopt constant current drive mode, it can avoid the current fluctuation caused by the change of LED forward voltage. At the same time, the constant current makes the brightness of the LED stable, and it is also convenient for LED lamp manufacturers to ensure the consistency of products when mass production is implemented. Therefore, many manufacturers have already Fully recognizing the importance of driving power, many LED lamp manufacturers have abandoned the constant voltage method, and chose a slightly higher cost constant current method to drive LED lamps.
Some manufacturers worry that the use of electrolytic capacitors on the power supply drive board will affect the life of the power supply. In fact, it is a misunderstanding. For example: if you choose a high-temperature electrolytic capacitor with a temperature of 105 degrees and a life of 8000 hours, according to the commonly used method of estimating the life of electrolytic capacitors, every 10 degrees reduction , Double the life expectancy ", then it has a working life of 16000 hours in a 95-degree environment, 32,000 hours in an 85-degree environment, and 64000 hours in a 75-degree environment. If the actual working temperature is lower, Then the lifespan will be longer! From this point of view, as long as the use of high-quality electrolytic capacitors has no effect on the life of the driving power supply!
It is also worth noting the attention of LED lamps and lanterns companies: As LEDs emit a lot of heat during the work process, the junction temperature of the die rises rapidly. The higher the LED power, the greater the heating effect. The increase in LED chip temperature will lead to the performance of light emitting devices The change of electro-optical conversion efficiency and the attenuation of electro-optical conversion efficiency, or even failure in severe cases, according to experimental tests show that: every time the temperature of LED rises by 5 degrees Celsius, the luminous flux drops by 3%. Try to increase the heat dissipation area of ​​the LED light source and reduce the working temperature of the LED. If conditions permit, it is good to separate the power supply part from the light source part. It is not advisable to blindly pursue small size and ignore the working temperature of the lamp and power supply . 