LED powered at 220 Volts

LED only works at low voltages and still need to use a series resistor. Not a good idea to limit the current at higher voltages using a resistance due to the power dissipated will be too high and the resistance will burn.


You can use an LED 220 as having a capacitor in series with the current limit. The advantage is that the capacitor is not heated! The paper is zener diode to protect the LED from high voltages. During the positive half cycle limits the voltage D1 in the LED and R1 to 2.7 volts. During the negative half cycle D1 acts as a normal diode prevent a high voltage gain. If we use an ordinary diode in place of the zener then the LED will be destroyed due to the high current