Abstract: An LED circuit includes a series of LED devices, a power supply circuit and a signal control circuit. Each of the LED devices includes an LED unit and an integrated circuit unit having a specific serial number and receiving an electrical parameter. The signal control circuit is coupled to the power supply circuit and the series of LED devices, and has a loaded status. The signal control circuit changes the loaded status in response to a control signal so as to cause the electrical parameter to have a variation, the variation of the electrical parameter generates a signal code having an information, all the integrated circuit units receive the signal code, and a specific LED unit will be driven by a corresponding integrated circuit unit when the signal code corresponds to the specific serial number of the corresponding integrated circuit unit.