US Patent 7190563 Electrostatic discharge protection in a semiconductor device

An electrostatic discharge (ESD) protection circuit for protecting a circuit from an ESD event, the ESD protection circuit comprises a metal-oxide semiconductor (MOS) device including a gate terminal, a first source/drain terminal, a second source/drain terminal and a bulk terminal, the bulk and first source/drain terminals being operatively coupled across the circuit to be protected, the gate and second source/drain terminals being coupled together; and a voltage generation circuit coupled between the bulk and gate terminals of the MOS device. The voltage generation circuit is configured to generate a voltage difference between the bulk and gate terminals of the MOS device during at least a portion of the ESD event. In this manner, a current handling capability of the MOS device is increased, thereby advantageously enabling a smaller sized device having a significantly smaller capacitance associated therewith to be employed in the ESD protection circuit.