Embodiments of an electrostatic discharge (ESD) protection device and a method for operating an ESD protection device are described. In one embodiment, an ESD protection device includes a primary ESD protection unit electrically connected to a first node and to a second node and configured to shunt current in response to an ESD pulse received between the first and second nodes and a secondary ESD protection unit electrically connected to the primary ESD protection unit and to the second node and configured to shunt current in response to the ESD pulse to keep an output voltage of the ESD protection device to be within a safe operating voltage range of a device to be protected. Other embodiments are also described.