A 16 Kb Spin-Transfer Torque Random Access Memory With Self-Enable Switching and Precharge Sensing Schemes

Abstract

Spin-transfer torque magnetic random access memory (STT-MRAM) is considered one of the most promising non-volatile memory candidates thanks to its excellent performance in terms of access speed, endurance, and compatibility to CMOS. However, high power supply voltage is required in the conventional STT-MRAM writing circuit, which results in high power consumption (e.g.,∼10 pJ/bit). In addition, it suffers from stochastic switching behavior and process voltage temperature variations. These make power-efficient and reliable write/read circuits become critical challenges. In this paper, we present novel circuits and architectures to build a 16 kb STT-MRAM design with low power and high reliability. For example, the self-enable switching scheme reduces the power consumption effectively and the fore-placed sense amplifier improves the robustness to process variation. Using an accurate compact model of 65 nm STT-MRAM and a commercial CMOS design kit, mixed transient and statistical simulations have been performed to validate this design.

Self-rectifying resistive memory in passive crossbar arrays

“…Considering these requirements, there are several non-volatile memories which are regarded as potential storage-class memories combining the advantages of main memories (random-access memory (RAM)) and data storage. They include ferroelectric RAM (FRAM) 8 , spin-torque-transfer RAM (STT-RAM) 9 , phase-change RAM (PcRAM) 10 , and resistive RAM (RRAM) 11 . Thus far, these have not been commercialized as standalone storage-class memories due to a few shortcomings.…”

Testing STT-MRAM: Manufacturing Defects, Fault Models, and Test Solutions

“…Examples are write-verify-write scheme and self-write-termination scheme. Readers who are interested in this topic are directed to works in [30,[99][100][101][102]. Wr_en Data_in P1 N1 P2 N2 write operation…”

“…Based on this sense amplifier, different variants have been proposed in the literature to incorporate various functionalities such as reliability enhancement and offset cancellation. More works about sense amplifier designs for STT-MRAMs can be found in [99,101,102,[104][105][106][107].…”

Robustness of Voltage-induced Magnetocapacitance

“…The magnetic states of MTJs can also be manipulated by the current induced spin-transfer torque (STT) effect 13 – 17 . More applications have become possible, e.g., magnetic random access memories (MRAMs) 18 – 21 , logic-in-memory circuits 22 , 23 and random number (RN) generators 24 , 25 . More recently, neuromorphic computing using spin-torque MTJ oscillators has been developed 26 .…”