Design of Fixed Cell-Based Programmable Logic Gate Using Quantum-Dot CA for Efficiency and Reliability of Digital Systems

Quantum-dot cellular automata (QCA) has recently been highlighted as a next-generation circuit design technology that can replace existing CMOS technology due to its advantages of maintaining very low energy consumption, small area requirements, and low latency. In this study, we propose a fixed cell-based programmable logic gate (FPLG) using QCA capable of multiple functions on a single gate platform. The proposed FPLG determines the value of a cell through cell interaction by controlling three enable inputs, and can perform seven different 2-input functions and one 3-input function. The proposed cell interaction-based operation was physically verified using the distance between electrons, and all circuits were simulated to confirm normal operation and accurate performance. It has also been explored for several PLG applications and has been confirmed to be an application-friendly gate. The proposed FPLG is compared in various performances with existing PLGs, and achieves at least 130% improvement in design cost. In the design of medium and large circuits, reducing the number of gates is a significant development task that simplifies circuit design and improves the efficiency and reliability of digital system manufacturing.