Energy saving system applied to universal serial bus

摘要

An energy saving system applied to universal serial bus (USB) includes a detecting circuit and at least one switching circuit. The detecting circuit is connected with a USB port to detect a power supply signal of the USB port. The switching circuit is connected with the detecting circuit and switches ON or OFF between a power supply and a load according to a detecting result of the detecting circuit. The above-mentioned energy saving system is able to detect the power supply signal to automatically switch the power ON or OFF for saving energy and increasing using convenience.