Protection circuit

A protection circuit, coupled to a bounding pad, comprising:

• a trigger circuit comprising a first transistor of a first conductivity type and a second transistor of the first conductivity type coupled in series between the bonding pad and a ground terminal further comprising a resistor, wherein the trigger circuit detects whether a transient event occurs on the bonding pad;
• and
• a discharge circuit, coupled between the bonding pad and the ground terminal and controlled by the trigger circuit,
• wherein, 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 bonding pad and the ground terminal, and
• wherein:
• the first transistor comprises a first electrode terminal coupled to the bonding pad, a second electrode terminal coupled to a first node, and a control electrode terminal,
• the second transistor is coupled between the first node and the ground terminal, and
• the resistor is coupled between the control electrode terminal of the first transistor and the discharge circuit.