Radiation-Hardened 0.3–0.9-V Voltage-Scalable 14T SRAM and Peripheral Circuit in 28-nm Technology for Space Applications

Abstract

Conventional radiation-hardened cells of static random access memory (SRAM) are not robust enough in 28 nm technology, due to partial immunity of single-event upset (SEU) effect (Quatro-based cells) or insufficient critical charges in sensitive nodes (conventional stacked cells). The reduction of read noise margin (RNM) at the low supply voltage (VDD) confines these cells from low VDD applications. We propose a novel interleaving stacked-14T (ILS-14T) cell which prevents voltage transient from propagating to other redundancies. The ILS-14T cell can be resilient to both 0–1 and 1–0 upsets by injecting 12 mA in sensitive nodes. The critical charges of the ILS-14T cell are substantially larger than most other hardened cells at VDD from 0.3 to 0.9 V. The RNM of the ILS-14T cell is two times of most Quatro-based cells at 0.3 V VDD and larger than most cells at 0.6 and 0.9 V VDD. The area of occupation is 334% of the conventional 6T cell, which equals other 14T cells. The static–dynamic decoder array with 20%–40% area penalty and 116%–132% delay of rising edge, when compared with the conventional one, reduces the read failure rate by preventing single event transients (SETs) from propagating to unexpected word lines (WLs).