A System Health Indicator for the Distributed Minority and Majority Voting Based Redundancy Scheme

The distributed minority and majority voting-based redundancy (DMMR) scheme was proposed as an efficient alternative to the conventional N-modular redundancy (NMR) scheme for the design of mission and safety-critical circuits and systems. However, only a basic implementation of the DMMR scheme was considered with no provision for indicating any fault or error in the DMMR system when they might occur. In this context, this paper presents the novel design of a generic system health indicator (SHI) for the DMMR scheme. Compared to the basic DMMR system, the DMMR system with the proposed SHI can provide concurrent information about the state of the system, i.e., whether the system is healthy or not. This helps to improve the observability of the DMMR system which could be useful during the online testing and/or troubleshooting of any faulty zones in the system, pre-emptively or during any scheduled maintenance. Example DMMR systems and their corresponding NMR systems without and with SHI have been implemented using a 32/28nm CMOS process and compared. On average, the DMMR systems with the proposed SHI report 6.5× improvement in a normalized figure of merit compared to the corresponding NMR systems incorporating SHI.