Patent ID: 8432651

Claim:
An apparatus for providing protection from transient electrical events, the apparatus comprising: an integrated circuit; a pad on a surface of the integrated circuit; a configurable protection circuit disposed on a p-type substrate of the integrated circuit, wherein the configurable protection circuit is electrically connected to the pad, and wherein the configurable protection circuit comprises a plurality of subcircuits arranged in series, and wherein selection of one or more of the plurality of the subcircuits for operation determines at least one of a holding voltage or a trigger voltage of the configurable protection circuit, wherein each of the plurality of subcircuits comprises: a p-well configured to operate as a base region; an n-type emitter region disposed in the p-well; an n-type collector region disposed in the p-well and spaced away from the n-type emitter region; a conductive plate positioned adjacent the p-well and between the n-type emitter region and the n-type collector region; an n-type isolation structure surrounding the p-well; and a resistor electrically connected between the conductive plate and the n-type emitter region, wherein the n-type emitter region, the p-well, and the n-type collector region are configured to operate as an NPN bipolar transistor, and wherein the p-type substrate and the n-type isolation structure are configured to operate as a diode, wherein the plurality of subcircuits comprises one or more subcircuits of a first type and one or more subcircuits of a second type different than the first type, wherein each subcircuit of the second type further comprises a PNP bipolar transistor cross-coupled with the NPN bipolar transistor.