An electrostatic discharge (ESD) protection circuit is coupled between first and second power supply buses. The ESD protection circuit includes a detection circuit; a pull-up circuit, coupled to the detection circuit, comprising at least a first n-type transistor; a pull-down circuit, coupled to the pull-up circuit, comprising at least a second n-type transistor; and a bypass circuit, coupled to the pull-up and pull-down circuits, wherein the detection circuit is configured to detect whether an ESD event is present on either the first or the second bus so as to cause the pull-up and pull-down circuits to selectively enable the bypass circuit for providing a discharging path between the first and second power supply buses.