Electronic device, intelligent signal transmission system and power-saving control method of electronic device and intelligent signal transmission system

A power-saving control method includes the following steps that conditions of data transmission of a signal transmission port of an electronic device and a display device are detected; whether the electronic device transmits audio video data to the display device through the signal transmission port or not is judged; when the electronic device transmits the audio video data to the display device through the signal transmission port, whether duration time used for transmitting the audio video data to the display device through the electronic device is larger than or equal to preset duration time or not is judged; when the duration time used for transmitting the audio video data to the display device through the electronic device is larger than or equal to the preset duration time, backlight of a display unit of the electronic device is automatically controlled to be turned off. The invention further provides the electronic device and an intelligent signal transmission system. The conditions of transmitting the audio video data to the display device through the signal transmission port of the electronic device can be detected, so that the backlight of the display unit of the electronic device is automatically controlled, and power energy can be saved while using of a user is not affected.