Abstract: An interface device includes an NPN structure along a horizontal surface of a p-doped substrate. The NPN structure has a first n-doped region coupled to an output terminal, a p-doped region surrounding the first n-doped region and coupled to the output terminal, and a second n-doped region separated from the first n-doped region by the p-doped region. The interface device also includes a PNP structure along a vertical depth of the p-doped substrate. The PNP structure includes the p-doped region, an n-doped layer under the p-doped region, and the p-doped substrate. Advantageously, the interface device can withstand high voltage swing (both positive and negative), prevent sinking and sourcing large load current, and avoid entering into a low resistance mode during power down operations.

Abstract: An interface device includes an NPN structure along a horizontal surface of a p-doped substrate. The NPN structure has a first n-doped region coupled to an output terminal, a p-doped region surrounding the first n-doped region and coupled to the output terminal, and a second n-doped region separated from the first n-doped region by the p-doped region. The interface device also includes a PNP structure along a vertical depth of the p-doped substrate. The PNP structure includes the p-doped region, an n-doped layer under the p-doped region, and the p-doped substrate. Advantageously, the interface device can withstand high voltage swing (both positive and negative), prevent sinking and sourcing large load current, and avoid entering into a low resistance mode during power down operations.