After the advent of the LED era, we can see it in all aspects of life, whether it is in the automotive field, smart field or industrial field, because of its high efficiency, energy saving, long life, environmental protection and other characteristics, it has become a modern lighting Technical options, and gradually applied to lighting. A key factor that drives people's attention to LED lighting technology is that it greatly reduces energy consumption and enables long-term reliable work. Today we will give you an extended introduction to LED lighting drive circuits from a practical LED circuit.
This article starts with a circuit using a constant current source. The main component of the circuit, the transistor, requires a voltage of 400V or more and a power of 10W or more, such as MJE13003, MJE13005, etc., and a heat sink is added. The filter capacitor C has a capacity of 4.7uF, and the withstand voltage must be 400V or more. The current of the light-emitting tube is determined by the adjustment of R2. For easy adjustment, a variable resistor can be adjusted and then replaced with a fixed resistance of the same resistance. The number is less than a dozen, and the maximum can reach more than 90. Although some costs are increased, the use effect is much better than that of a circuit that only uses a resistor current limit. Even if the voltage fluctuation is large, the circuit can still keep the current constant This is very beneficial to the life of the light emitting tube, and the current in this range can be kept basically constant. The number of light-emitting tubes used in this circuit should not be too small, and the lower the efficiency, the lower the efficiency. The total power consumption of this circuit is about 6W.