Self-Triggered SCR in Output Driver for Enhanced ESD Robustness

This paper presents an enhanced ESD (electrostatic discharge) protection solution for output drivers without additional protection devices. The output drivers in low and high voltage CMOS technologies are often susceptible against the ESD stresses with and without the ESD protection devices. The proposed structure shows significantly improved ESD immunity using a consolidated NPBL (N plus buried layer) mask underneath an ESD protection SCR (silicon controlled rectifier) for the VCC to the ground and the output drivers, which are effectively triggered when ESD events occur. This consolidated NPBL plays an important role of a booster for faster triggering than other parasitic devices.