Single Event Transient (SET) Mitigation Circuits With Immune Leaf Nodes

摘要

In a spacecraft, flip-flops take part in holding operational configuration for long durations. Single event transients (SETs) at control inputs of such flip-flops can culminate in single event upsets (SEUs). An SEU may cause loss of one or more mission objectives or service disruption or life reduction of the spacecraft. Many radiation-hardened-by-design (RHBD) circuits are presented in the literature to improve the reliability of control inputs of flip-flops. However, leaf nodes of these circuits interfaced with control inputs remain vulnerable to SETs. This article proposes two novel SET mitigation circuits with immune leaf nodes and demonstrates it through a few case studies. The proposed circuits improve SET hardness at control inputs of flip-flops by at least three times compared to unhardened inputs. Comparison of important parameters with the published SET mitigation approaches shows that the proposed circuits require lesser transistors and consume low power.