Patent ID: 9716382
Date: 2017-07-25
CPC Classifications: H02H

Claim:
1. An electrostatic protection circuit that is connected via a first node to a first terminal to which a first potential is supplied, and is connected via a second node to a second terminal to which a second potential lower than the first potential is supplied, the electrostatic protection circuit comprising: a first impedance element, one end of the first impedance element being connected to one of the first node and the second node, and the other end of the first impedance element being connected to a third node; a clamp element, one end of the clamp element being connected to the third node, and the other end of the clamp element being directly connected to the other of the first node and the second node; a first transistor that is connected between the one of the first node and the second node and a fourth node, and that turns on in accordance with an increase in voltage generated in the first impedance element; at least one impedance element that is connected between the fourth node and the other of the first node and the second node, and that includes a second impedance element; a second transistor that turns on in accordance with an increase in voltage generated in the second impedance element, and that increases current flowing in the first impedance element; and a discharge circuit that allows current to flow from the first node to the second node when the second transistor is in an on state.