Radiation-hardened read-decoupled low-power 12T SRAM for space applications

In advanced technology, static random-access memory (SRAM) cells used in space are highly sensitive to charge variations caused by high-energy particle strikes, which cause soft-error. Therefore, it is imperative for an SRAM to withstand this harsh environment. However, 6T cells are unable to function reliably in such a place. In order to address this, a radiation-hardened read-decoupled 12T (RHRD12T) SRAM cell is proposed in this paper. The relative strength of RHRD12T is estimated by comparing it with other contemporary cells such as NS10T, PS10T, RHBD10T, QUATRO12T, QUCCE12T, and RHD12T on various major design metrics. Due to the read-decoupled nature of RHRD12T, it shows the highest read stability. It also consumes the lowest hold power compared to all other considered cells, except NS10T. Moreover, RHRD12T exhibits the highest write ability due to the use of two extra access transistors and the poor driving ability of the internal nodes. In terms of write delay, RHRD12T shows an improvement of 1.02x/1.06x/1.07x/1.08x over NS10T/RHD12T/PS10T/RHBD10T at V-DD = 1 V. Moreover, RHRD12T is capable of tolerating the highest amount of critical charge among all other comparison cells and is the least susceptible to single-event upsets. All the aforementioned improvements are obtained at the cost of longer read delay.