Radiation Hardening by Design Techniques for the Mutual Exclusion Element

Circuits in advanced CMOS technology are increasingly more sensitive to transient pulses caused by radiation particles that strike vulnerable circuit components, specially turned off transistors, often generating multiple voltage upsets. Towards mitigating these issues, this paper presents a novel Radiation Hardened by Design (RHBD) mutual exclusion element (mutex) that incorporates multiple RHBD techniques with reduced area overhead. We compared our proposed circuit to the baseline and the state-of-the-art designs, in terms of resiliency to Single Event Transients (SET) and Single Event Upsets (SEU), request to grant latency, and area overhead. Results shows that the proposed circuit mitigates SET and prevents SEU events incurring in 1.42x performance and 5.1x transistor area overhead compared to the baseline (unhardened) design. On the other hand, the proposed mutex circuit improves SEU resiliency at outputs, achieving 0.58x transistor area and 0.62x latency compared to the state-of-the-art RHBD mutex that uses modular redundancy.