A symmetrical layout technique for an electrostatic discharge ESD device and a corresponding power supply network is presented. The ESD device protects an electronic circuit against an overvoltage or overcurrent and contains a first contact area to establish an electrical contact with a first supply rail, a second contact area to establish an electrical contact with a second supply rail, and a third contact area to establish an electrical contact with a third supply rail. The first and third supply rails provide a first supply voltage, and the second supply rail provides a second supply voltage. Within the ESD device, an axis of symmetry passes through the second contact area, and the first contact area and the third contact area are arranged on opposite sides with regard to the axis of symmetry. The symmetrical layout technique allows flipping the orientation of the ESD device with regard to the supply rails.