A portable terminal has a main machine body and a cell, one of the main machine body and the cell is arranged a pushing button moving axially, and a compression spring is arranged between the pushing button and the one of the main machine body and the cell...

A smooth switching device and method for double power supplies. The devices includes a main/backup power supply switching unit (1), a relay control unit (3), a charge management unit (2), a main power supply switching auxiliary unit (4) and a backup power ...