Method for driving alternate current of light emitting diode and operating voltage thereof

A method for driving an alternate current of a light emitting diode, comprising:

• an AC obtaining measure, for obtaining an AC sine wave signal having positive and negative half-cycle waveforms;
• a power modulation measure, for modulating an impedance of the first and second LED groups according to at least two conducting directions that are in opposite directions with each other and connected in parallel and an AC sine wave signal of the AC obtaining measure to change the positive half-cycle waveform of the AC sine wave signal to comply with an operation range of the positive half-cycle driving signal of the first LED group, and the negative half-cycle waveform of the AC sine wave signal to comply with an operation range of the negative half-cycle driving signal of the second LED group;
• and
• a power driving measure, for driving the first LED group by the positive half-cycle driving signal of the power modulation measure and driving the second LED group by the negative half-cycle driving signal, wherein the first and second LED groups are driven sequentially according to operating cycles of the positive and negative half-cycle driving signals.