Led driver, led system and signal transmitting method for led

An LED system configured to communicate with an external device, the LED system comprising:

• a LED;
• a controller, coupled with the LED;
• and
• an interface circuit, configured to be coupled between the controller and the external device, the interface circuit comprising:
• an interface port configured to be coupled to the external device,
• an analog interface module, coupled between the interface port and the controller and configured to transmit an analog signal between the external device and the controller via the interface port in a first mode,
• a digital interface module, coupled between the interface port and the controller and configured to transmit a digital signal between the external device and the controller via the interface port in a second mode and a third mode, and
• a power supply module, coupled to the interface port and configured to provide energy to the external device via the interface port in the first mode and the third mode.

A method for transmitting a signal between an LED and an external device, the method comprising:

• transmitting the signal by an interface circuit coupled between the external device and a controller, wherein the controller is coupled with the LED and the interface circuit is coupled with the external device via an interface port, wherein the transmitting of the signal comprises:
• transmitting an analog signal between the external device and the controller via the interface port by an analog interface module in a first mode,
• transmitting a digital signal between the external device and the controller via the interface port by a digital interface module in a second mode and a third mode, and
• providing energy to the external device via the interface port by a power supply module in the first mode and the third mode.