Patent ID: 6690555
Filing Date: 2004-02-10
Classification: H01L,H03K

Abstract:
An electrostatic discharge protection circuit for a plurality of signal nodes, the electrostatic discharge protection circuit comprising:a positive electrostatic discharge node; a negative electrostatic discharge node; a first electrostatic discharge diode coupled between a first one of the signal nodes and the positive electrostatic discharge node; a second electrostatic discharge diode coupled between the first signal node and the negative electrostatic discharge node; a third electrostatic discharge diode coupled between a second one of the signal nodes and the positive electrostatic discharge node; a fourth electrostatic discharge diode coupled between the second signal node and the negative electrostatic discharge node; and a trigger switch connected to the positive and negative electrostatic discharge nodes, the trigger switch having: a first transistor having a first source/drain terminal coupled to the positive electrostatic discharge node; a second transistor having a first source/drain terminal coupled to the negative electrostatic discharge node, the second transistor having a second source/drain terminal coupled to a second source/drain terminal of the first transistor; a first resistance coupled between the positive electrostatic discharge node and a gate terminal of the first transistor; a first capacitance coupled between the negative electrostatic discharge node and the gate terminal of the first transistor; a second resistance coupled between the negative electrostatic discharge node and a gate terminal of the second transistor; and a second capacitance coupled between the positive electrostatic discharge node and the gate terminal of the second transistor wherein the trigger switch is operable to provide a low-resistance connection between the positive and negative electrostatic discharge nodes of the electrostatic discharge protection circuit in response to an electrostatic discharge event.