Patent ID: 9006782
Filing Date: 2015-04-14
Classification: H01L

Abstract:
1. An apparatus comprising: a substrate; a first well region of a first type in the substrate; a second well region of the first type in the substrate adjacent the first well region; a third well region of a second type opposite the first type, wherein the third well region is positioned in the substrate between the first and second well regions; a fourth well region of the second type positioned on a side of the first well region that is opposite the third well region; a fifth well region of the second type positioned in the substrate on a side of the second well region that is opposite the third well region; a first diffusion region of the first type in the fourth well region; a second diffusion region of the second type in the first well region; a third diffusion region of the first type in the third well region; and a fourth diffusion region of the second type in the second well region; wherein the first diffusion region, the fourth well region, the first well region, and the second diffusion region are configured to operate as a first thyristor structure; wherein the third diffusion region, the third well region, the second well region, and the fourth diffusion region are configured to operate as a second thyristor structure; wherein the second diffusion region, the first well region, the third well region and the third diffusion region are configured to operate as a third thyristor structure; wherein a junction between the second well region and the fourth diffusion region is configured to operate as a first diode structure; wherein a junction between the fourth well region and the first diffusion region is configured to operate as a second diode structure; and wherein a junction between the fifth well region and the second well region is configured to operate as a third diode structure.