Author : Anil Kumar Rajput 1
Date of Publication :31st January 2022
Abstract: The current computing systems are facing von Neumann bottleneck (VNB) in modern times due to the high prominence on big-data applications such as artificial intelligence and neuromorphic computing. In-memory computation is one of the emerging computing paradigms to mitigate this VNB. In this paper, a memristor-based robust 7T2M Nonvolatile-SRAM (NvSRAM) is proposed for energy-efficient In-memory computation. The 7T2M NvSRAM is designed using CMOS and memristor with a higher resistance ratio, which improved the write margin by 74.44% and the energy consumption for read and write operation by 5.10% and 9.66% over conventional 6T SRAM at the cost of increment in write delay. The read decoupled path with the VGND line enhances the read margin and read path Ion/Ioff ratio of 7T2M NvSRAM cell by 2.69× and 102.42%, respectively over conventional 6T SRAM. The proposed cell uses a stacking transistor to reduce the leakage power in standby mode by 64.20% over conventional 6T SRAM. In addition to the normal SRAM function, the proposed 7T2M NvSRAM performs In-Memory Boolean Computation (IMBC) operations such as NAND, AND, NOR, OR, and XOR in a single cycle without compute-disturb (stored data flips during IMC). It achieves 4.29-fJ/bit average energy consumption at 1.8 V for IMBC operations
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