Design of embedded SCR device to improve ESD robustness of stacked-device output driver in low-voltage CMOS technology

This study proposes a novel design for an embedded silicon-controlled rectifier (SCR) device to improve the electrostatic discharge (ESD) robustness of a stacked-device output driver. A 3 × VDD-tolerant stacked-device output driver with embedded SCR is demonstrated using a 0.18 μm CMOS process with VDD of 3.3 V. This design is verified in a silicon chip, and it is shown that the proposed output driver with embedded SCR can deliver an output voltage of 3 × VDD. The ESD robustness can be improved without the use of any additional ESD protection device or layout area. Furthermore, the proposed design can also be used for an n × VDD-tolerant stacked-device output driver to improve its ESD robustness.