The scope of LEDs today is huge and is constantly expanding. But not so long ago, this device could only be found in display circuits. It was not designed for a heavy load. More and more powerful devices are being developed that can work in the field of lighting. Spotlights and lamps based on high-power LEDs appeared. They are used in the automotive industry, participate in road lighting and regulate traffic with the help of powerful traffic lights. Household appliances have appeared that are a good analogue of existing lighting devices. LED lights are starting to appear in our apartments, stairwells and offices.
The unusual properties of LEDs have long attracted the attention of designers. In the automotive industry, parking lights and brake lights based on these devices are used. One of the directions in the design of the car is the replacement of obsolete lamps inside the cabin with LEDs. They are also widely used forinstrument panel displays and interior lighting. Smooth turning on of LEDs is one of the promising solutions in car tuning. For example, the light in the cabin can smoothly light up or go out, respectively, when opening or closing the doors. Or the backlight on the control devices can be smoothly turned on / off when a device is activated, for example, side lighting.
It is not difficult to organize the smooth turning on of LEDs, for this you need to assemble a small circuit. If the load power consumption is small, then you can use a simple polar capacitor by soldering it in parallel with the lighting device. Do not forget about the polarity (the positive terminal of the capacitor must be connected to the anode wire of the LED). Negative, respectively, with the cathode. Capacitor may explode if connected incorrectly! Also pay attention to the maximum voltage at which such a circuit operates. It should not exceed the allowable operating voltage of the capacitor.
Correctly assembling the circuit, you can immediately see the smooth turning on of the LEDs. It is not recommended to increase the capacitance of the capacitor by more than 2200 μF, since exceeding this value will lead to rapid wear of the switching equipment. The fact is that when voltage is applied to the circuit, the capacitance begins to charge. At the first moment of time, a decent starting current occurs, which can damage the relay contacts. The above capacitor capacitance allows for a smoothturning on the LEDs with a time delay of up to 3-5 seconds. This happens exponentially, meaning that initially you get approximately 20-40 percent of the lighting in the cabin. For a few seconds after that, the LEDs turn on smoothly to the nominal mode of their operation.
To work with more powerful lighting devices, one capacitor is not enough. The smooth switching on of such devices is organized using circuits where the current consumption of the LEDs is controlled by the output stage, assembled, for example, on transistors. The time delay in this case is implemented by various electronic circuits.
