Efficient Silicon-Controlled Rectifier Devices for Cross-Power-Domain ESD Protections

Electrostatic discharge (ESD) protection is a challenging issue for integrated circuits (ICs) with cross-power-domains. In this article, an efficient ESD protection scheme based on silicon-controlled rectifier (SCR) for cross-power-domains is proposed and verified by silicon data. The conventional anti-parallel diodes are modified to SCR configurations to reduce the voltage across the transistors in the interface circuits under the cross-power-domain ESD events. The existing power clamp circuit facilitates SCR triggering, offering a good trigger characteristic. Measured results demonstrate that the proposed protection scheme has a high ESD robustness with an acceptable area increase and can be implemented easily.