Enhanced Critical Charge (Q cr ) and Highly Reliable Read-Decoupled Radiation-Hardened 14T SRAM cell for Aerospace Application

Abstract

Due to technological advancements, the size of transistors and the spacing between them is decreasing, resulting in a reduction in the critical charge of sensitive nodes. This decrease in critical charge makes these nodes more susceptible to disturbances and errors in static random access memory (SRAM) cells used in aerospace applications. To address this, a proposed 14T SRAM cell with polarity hardening technology is introduced in this paper, which reduces the number of sensitive nodes and enables recovery from single-event-multiple-effect (SEME) based on all single-event upset (SEU) recovery techniques. The simulation results conducted on the United Microelectronics Corporation (UMC) 65 nm CMOS commercial standard process demonstrate that the proposed 14T SRAM cell reduces both SEU and SEME. A comparative study is performed between the proposed 14T cell and other radiation-hardened SRAM cells, including DICE, SAR14T, RSP14T, RHBD14T, and NRHC14T, to assess the relative performance of the proposed cell. The proposed 14T cell for SRAM exhibits 40.42% and 21.39% improvements in write stability compared to existing cells like DICE and RSP14T, as well as 25.08% and 19.09% improvements in read stability compared to RHBD14T and RSP14T. It also shows enhancements of 81.88%, 76.82%, 57.83%, and 10.25% in critical charge value compared to RHBD14T, NRHC14T, SAR14T, and RSP14T, respectively, better stability, and improved overall performance, making it suitable for aerospace applications. Monte Carlo (MC) simulations have verified its ability to recover from SEU and SEME, with zero percent failure probability during read, write, and hold operations at different supply voltages.