US Patent 10033177 Electrostatic protection circuit

An electrostatic protection circuit includes a trigger circuit that is connected between a first power line and a second power line. The trigger circuit is configured to output a trigger signal in response to a voltage fluctuation between the first and second power lines. A shunt element has a main current path between the first power line and the second power line and is controllable to be on and off using the trigger signal. A control circuit is configured to supply a control signal to turn off the shunt element when a current value of the main current path of the shunt element exceeds a predetermined threshold value.