LED display is a current control device, LED drive LED drive power is actually about to alternating current into a constant current or constant voltage DC circuit device. What is the link between the two does, here to answer your questions in detail.
led display Unlike ordinary incandescent bulbs can be directly connected to 220V AC mains. LED drive power requirements of almost demanding, its operating voltage is generally 2 ~ 3V DC voltage, it must design of complex circuits. Different uses LED lights to be equipped with different power adapter. LED device for LED drive power conversion efficiency, effective power, constant current accuracy, power life, electromagnetic compatibility requirements are very high, a good drive power must consider these factors, as driving power of the entire LED lamps It acts like the human heart just as important. The main task of LED driver is to convert AC voltage constant current DC power, and simultaneously match the LED voltage and current. Another task is to make LED drivers LED load current under the influence of various factors can be controlled at the level of pre-designed.
LED Drive Overview
led luminous display is conditional. The forward voltage is applied to both ends of the PN junction, so that in itself form a PN junction level (actually a series of energy levels), electronic transitions and produce photons to emit light at this level. Therefore, the need to increase the voltage across the PN junction to drive the LED light. Also, because LED is a feature-sensitive semiconductor device having a negative temperature characteristic, and thus in the application process needs to be stable working conditions and protection, resulting in LED "driven" concept.
LED contact people know, LED forward voltage characteristics is very steep (forward dynamic resistance is very small), to give the LED power supply is more difficult, not as a direct voltage source power like ordinary incandescent Otherwise, voltage fluctuations increased slightly, the current will increase to the extent that the LED burned. To stabilize the LED current to ensure reliable operation of the normal LED, a variety of LED driver circuit is made.
led display driver circuit is simple and some [only 1 to 2 ballast element), and some complex [with a number of electronic elements); some for small power LED arrays, some for high-power LED array; Some DC power supply, and some use the AC power supply; some good, long life, and some poor performance, high failure rate, affecting LED life.