A multi-node-upset-resilient 14T SRAM with high read stability for space applications

Abstract

This paper proposes a voltage-booster read-decoupled radiation-hardened 14T (BDRH14T) SRAM cell. In harsh environments such as space, radiation can flip the stored data in memory cells, resulting in soft errors, including single-event upset (SEU) and single-event multi-node upset (SEMNU). Moreover, with the continued scaling of CMOS technology, the reduced spacing between transistors lowers the critical charge, increasing the vulnerability of SRAM cells to radiation-induced faults. The proposed BDRH14T cell is designed to recover its original stored data at all sensitive nodes even under a high injected charge of 150 fC. Additionally, it is capable of self-recovery from SEMNU occurring at storage node pairs. In addition to its radiation hardness, the BDRH14T exhibits enhanced read stability and reduced power consumption, achieving high read static noise margin (RSNM) and hold static noise margin (HSNM), along with low hold power (HPWR). All simulations were conducted using a 90 nm CMOS technology, considering variations over a wide range of supply voltages (0.9-1.1 V) and temperatures (-30 degrees C-120 degrees C). The superior performance of BDRH14T is attributed to the adoption of a voltage booster, a read-decoupled architecture, and deliberate a trade-off in read and write access times (RAT and WAT).