Editing AC adapter (section)

===Auto-sensing adapters===
Some universal adapters automatically set their output voltage and maximum current according to which of a range of interchangeable tips is fitted; tips are available to fit and supply appropriate power to many notebook computers and mobile devices. Different tips may use the same connector, but automatically supply different power; it is essential to use the right tip for the apparatus being powered, but no switch needs to be set correctly by the user. The advent of switch-mode power supplies has allowed adapters to work from any AC mains supply from 100 to 240 V with an appropriate plug; operation from standard 12 V&nbsp;DC vehicle and aircraft supplies can also be supported. With the appropriate adapter, accessories, and tips, a variety of equipment can be powered from almost any source of power.

A "Green Plug" system has been proposed, based on [[Universal Serial Bus|USB]] technology, by which the consuming device would tell the external power supply what kind of power is needed.<ref>[https://www.engadget.com/2008/05/10/swtched-on-green-plug-tries-to-replace-the-worry-warts-part-1/ Green Plug tries to replace the worry warts] Engadget May 2008</ref>