A useful design methodology to implement the bi-directional electrostatic discharge (ESD) protection circuit with uni-directional ESD device was proposed. The proposed design methodology leverages the uni-directional ESD devices and diodes, those already verified and supported by the foundry, to build the bi-directional ESD protection circuit for the desired I/O applications. The circuit exhibits several advantages, including simplified design, reduced size, and compatibility with differential or multiinput signal applications. The experimental results have validated the effectiveness and usability of the proposed circuit in providing bi-directional ESD protection. This work contributes to the advancement of ESD protection design, offering a practical and efficient solution to meet the requirement of bi-directional ESD protection.