A regulator device includes a first switch, a second switch, a protecting circuit, and a driving circuit. The first switch is configured to receive power supply voltage. One terminal of the second switch and the first switch are coupled at a node. The other terminal of the second switch is coupled to ground. The protecting circuit is coupled to the node, and outputs at least one protecting signal according to the turn on/off state of the first switch and the second switch and the voltage of the node. The driving circuit is coupled to the first switch, the second switch, and the protecting circuit, and turns off the first switch or the second switch according the at least one protecting signal.