Bi-directional ESD protection circuit

摘要

A structure is designed with an external terminal (100) and a reference terminal (102). A first transistor (106) is formed on a substrate. The first transistor has a current path coupled between the external terminal and the reference terminal. A second transistor (118) has a current path coupled between the external terminal and the substrate. A third transistor (120) has a current path coupled between the substrate and the reference terminal.

主权项

1. A method of forming a circuit comprising:
forming a first device having a current path and a control terminal between an external terminal and a reference terminal, the external terminal coupled to receive a maximum positive voltage with respect to the reference terminal and a minimum negative voltage with respect to the reference terminal during normal circuit operation; forming a second device having a current path connected to the control terminal of the first transistor, the second device arranged to inhibit conduction of the current path of the first device in response to the maximum positive voltage; forming a third device having a current path connected to the control terminal of the first transistor, the third device arranged to inhibit conduction of the current path of the first device in response to the minimum negative voltage; connecting a first resistor between the external terminal and the current path of the second device; and connecting a second resistor between the current path of the third device and the reference terminal.