At 60 Hz of frequency, the current and voltage have the same phase change with addition of input power which is changed periodically. LED was turned on under the forward bias only and there was no current flow in reverse bias. In addition, the current was changed from 0 to maximum current, and the voltage was changed from 2.4 V, which is the turn on voltage of LED, to the maximum voltage of 3.6 V. In order to compare the thermal performance of LED at DC and AC mode, the corresponding simulation was carried out.