As LED production costs decline, more and more applications are beginning to adopt such components, including handheld devices, automotive electronics, and architectural lighting. LEDs are highly suitable for use as illumination sources due to their high reliability, good efficiency and ultra-fast response. Although the cost of incandescent bulbs is low, the cost of replacement can be expensive. Street lights are a good example. Changing a faulty light bulb often requires multiple people and a truck to be dispatched. Because of this, although LEDs and incandescent bulbs are roughly equivalent, many street lights use more reliable and more power-efficient LEDs.
Although incandescent lamps emit continuous spectrum, they are often used in traffic lights, such as green, red and yellow. This type of application requires a filter of a specific color to be added to the incandescent lamp, but it will cause 60% of the light energy to be wasted. LEDs can produce light of a specific color, and can be lit as soon as the power is turned on. Unlike incandescent lamps, which require 200ms of reaction time, the automotive industry has long used LEDs for lights. In addition, DLP video applications also use LEDs as the light source, replacing the original mechanical components with high-speed switching LEDs.
LED IV characteristics
Figure 1 shows the forward voltage characteristics of a typical InGaAlP LED. The LED circuit model can be represented as a voltage source in series with a resistor. This simple model is in good agreement with the actual measurement results. The voltage source is a negative temperature coefficient, so the forward voltage drops as the junction temperature increases. The InGaAlP LED (yellow and amber red) has a temperature coefficient between -3.0 and -5.2 mV/K, and the InGaN LED (blue, green and white) is between -3.6 and -5.2 mV/K. The negative temperature coefficient is one of the reasons why LEDs are difficult to connect in parallel, because the hotter the component will draw more current, the more current will cause its temperature to rise further, and finally become thermal runaway.
Figure 1: IV characteristic curve obtained with voltage source and series resistance as LED circuit model
Figure 2 shows the relationship between the output light intensity (light flux) and the operating current. It can be seen that the relationship between the output light intensity and the diode current is very close. The brightness of the LED can be adjusted by changing the forward current. In addition, this curve looks like a straight line when the current is small, but its slope becomes smaller as the current rises. This means that when the current is small, the output light intensity is doubled as long as the diode current is doubled. This is not the case when the current is large. At this time, the current doubles only increases the output light intensity by 80%. This feature is important for LEDs because it is driven by a switched-mode power supply and can experience large ripple currents. In fact, the cost of the power supply is determined to some extent by the allowable current: the higher the ripple current, the lower the cost of the power supply, but the output light intensity of the LED is also affected.
Figure 2: LED efficiency begins to drop after the current exceeds 1A
Round Industrial Lighting LED Driver
MOSO Round Industrial Lighting LED Driver has programmable output current. It is a brilliant design with advanced technologies. It`s designed for external assembling of round shape LED light fixtures, like round high bay, low bay lights, or flood lights, canopy lights, or horticulture lights used in industrial area, or factories, warehouses, and greenhouses.
The round industrial lighting led driver got global safety certifications, including UL, CE, TUV, CB, SAA, BIS, KC, etc. The LED control gear has universal input voltage, from 90~305Vac. It is a reliable product compatible with various application and different countries.
The perfect cooling design can ensure the product reliability and long lifetime for at least 10 years (50,000hours operation at least) minimum.
MOSO grants the product with 5 years global warranty. Customer can refer to Warranty policy, find the closest MOSO distributors or sales representatives, to get a local replacement in case of any failure.
Drivers with dimming 0~10V & PWM is available.
Round Industrial Lighting LED Driver
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