Energy-Efficient Dual-Node-Upset-Recoverable 12T SRAM for Low-Power Aerospace Applications

Abstract

With technology scaling, transistor sizing, as well as the distance between them, is decreasing rapidly, thereby reducing the critical charge of sensitive nodes. This reduction makes SRAM cells, used for aerospace applications, more susceptible to radiation as it can cause single-event upsets (SEUs) and also single-event multi-node upsets (SEMNUs). This article presents an energy-efficient dual-node-upsetrecoverable 12T SRAM cell for low-power aerospace applications, EDP12T, in 65-nm CMOS technology. The proposed cell mitigates SEUs as well as SEMNUs. To judge the relative performance of EDP12T, a comparative study is made between it and other radiation-hardened cells, RHM12T, QUCCE12T, QUATRO12T, RHD12T, SRRD12T, RHPD12T, RSP14T, LWS14T, SAR14T, and S8P4N16T. EDP12T can recover from SEUs injected at all the sensitive nodes and SEMNUs that have occurred at its internal nodepair. In addition, EDP12T also exhibits better write performance than most of the comparison cells. Among all the cells for comparison, EDP12T dissipates the lowest hold power, except RHM12T. In addition to these, it consumes the least energy during write mode and also consumes lower energy than most of the comparison cells during read mode. It also exhibits 1.08×/ 1.17×/ 1.37×/ 1.56×/ 2.32× higher read stability than S8P4N16T/ RHPD12T/ QUCCE12T/ QUATRO12T/ LWS14T. All these aforementioned improvements are obtained by the proposed cell while consuming 1.03×/ 1.06×/ 1.07×/ 1.08×/ 1.14×/ 1.43× lower area than SAR14T/ RHD12T/ S8P4N16T/ RSP14T/ LWS14T/ RHPD12T. However, these advantages come with a slight penalty in read delay.INDEX TERMS SRAM cell, read energy, write energy, hold power, read stability, write ability, single-event upset (SEU), single-event multi-node upset (SEMNU), critical charge, aerospace applications.

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

“…1) Hold mode: By connecting all wordlines (WL and WWL) to GND during the hold state, due to this both pairs of access transistors remain OFF. Bitlines (BL and BLB) are precharged to VDD during the hold state to reduce read delay [1]. For the hold state, only transistors P2, P3, N1, N4, and N8 keep ON, while the other transistors keep OFF.…”

“…The mentioned phenomenon of the wider spread of radiation ion strike and extensive charge diffusion in the storage element is responsible for the occurrence of the mentioned event. This event refers to the alteration of the state of the cell due to the impact of radiation, leading to the flipping of the stored data [1], [15].…”

“…These advancements have had a significant impact on various aspects of society, providing valuable benefits and ensuring safety. Among memory cells, static random access memory (SRAM) cells are preferred in aerospace applications to store data efficiently and reliably due to their high packing density and enhanced logic performance [1]. However, due to factors like continuous scaling, lower power supply, and higher frequencies, SRAM, is more susceptible to the harmful effects of radiation.…”

Double Node Upset Immune RHBD-14T SRAM Cell for Space and Satellite Applications

“…2(g). This design's greatest feature is its shorter write access time under PVT analysis [24]. The issue with this design is that it has poor read and write stability under worst-case corner and temperature analysis.…”

A High-Reliability 12T SRAM Radiation-Hardened Cell for Aerospace Applications

“…The SRAM cells working in the aerospace environments require high radiation resistance to cope with the complex impact of the environment. Therefore, redundant node reinforcement is often used to harden the design of the cells [ 7 ], and the radiation resistance of the cells is improved through redundant feedback mechanisms [ 8 , 9 ]. Over the years, various soft-error-recovery SRAM cells have been proposed [ 6 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ].…”