Initial-On ESD Protection Design with PMOS-Triggered SCR Device

A novel SCR design with "initial-on" function is proposed to achieve the lowest trigger voltage and the fastest turn-on speed of SCR device for effective on-chip ESD protection. Without using the special native device or any process modification, this initial-on design is implemented by PMOS-triggered SCR device, which can be realized in general CMOS processes. This initial-on SCR design also presents a high enough holding voltage to avoid latchup issue. The new proposed initial-on ESD protection design with PMOS-triggered SCR device has been successfully verified in a 0.25-mum CMOS process