A 20 nm robust single-ended boost-less 7T FinFET sub-threshold SRAM cell under process–voltage–temperature variations. (May 2016)

• Record Type: Journal Article
• Authors: Kushwah, C.B.; Vishvakarma, S.K.; Dwivedi, D.
• Is Part Of: Microelectronics journal. Volume 51(2016)
• Page Start: 75
• Page End: 88
• Publication Date: 2016-05
• Subjects: Boost-less -- FinFET -- Process–voltage–temperature -- SRAM -- Sub-threshold -- Ultra-low power; Microelectronics -- Periodicals; Microélectronique -- Périodiques; Microelectronics; Electronic journals; Journals - contents and abstracts; Periodicals; 621.3805
• DOI: 10.1016/j.mejo.2016.02.010
• Languages: English
• ISSNs: 0959-8324

Abstract

Abstract: A novel 20 nm FinFET based 7T SRAM cell is presented. Proposed 7T SRAM cell involves the breaking-up of feedback between the true storing nodes which enhances the write-ability of the cell at ultra-low voltage power supply without boosted supply and write assist. The read decoupling and feedback cutting makes proposed 7T SRAM cell more robust to process variations in sub-threshold regime. For proposed 7T SRAM cell, the mean and standard-deviation ( μ / σ ) ratio of hold static noise margin is 31.5% higher than that of conventional iso-area 5T SRAM cell at 0.5 V VDD. The 7T SRAM cell has 66.4% higher μ / σ of read margin as that of 5T SRAM cell at 0.25 V VDD. The write static noise margin of 7T SRAM cell is ~50% of VDD for all VDD values whereas 5T SRAM cell fails to write. During write '0', the proposed cell consumes only 0.11× power as that of 5T SRAM cell at 0.8 V VDD. The read operation of 7T SRAM cell consumes 0.34× lesser power than 5T SRAM cell read operation for all values of bit-line capacitances at 0.2 V VDD. At 0.2 V VDD, the 7T SRAM cell has 0.46× lower write '0' delay as that of 5T SRAM cell. The write delay of 7T SRAM cell is 0.32× lower as that of 5T SRAM cell at 0.8 V VDD. The techniques used by the proposed 7T SRAM cell allow it to operate at ultra-low voltage supply without any write assist in 20 nm FinFET technology node.