US Patent 11894674 Protection circuit

A power detection circuit is provided. The protection circuit is coupled to a pad and includes a trigger circuit and a discharge circuit. The trigger circuit includes a first transistor of a first conductivity type and a second transistor, also of the first conductivity type, which are coupled in series between the pad and a ground terminal. The trigger circuit detects whether a transient even occurs on the pad. The discharge circuit is coupled between the bonding pad and the ground terminal and controlled by the trigger circuit. In response to the transient event occurring on the bonding pad, the trigger circuit generates a trigger voltage to trigger the discharge circuit to provide a discharge path between the pad and the ground terminal.