An electrical-overstress (EOS) protection circuit for an electronic device includes series-connected resistors, a mode-control switch, and a bias circuit. The series-connected resistors are electrically coupled between an input and an output, and the mode-control switch is electrically coupled between the output and a ground. The bias circuit is electrically coupled to the input for generating a mode-control signal to control the mode-control switch. The bias circuit generates the mode-control signal in a way such that the mode-control switch is open in a normal mode and closed in an EOS mode.