A dynamic reference scheme to improve the sensing reliability of magnetic random access memory

Emerging magnetic random access memory (MRAM) has been considered as a promising candidate for the next generation high speed, low power and scalable nonvolatile memory technology. However many challenges and issues are still existing before its wide commercialization. One of the critical issues is its low sensing reliability due to the relatively small tunnel magneto-resistance (TMR) ratio of the magnetic tunneling junction (MTJ) and the increasing process variations etc. In this paper, we propose a new MRAM reference cell design as well as a novel dynamic reference scheme to improve the sensing reliability of MRAM. Using a physics-based MTJ model and a CMOS design kit, Monte-Carlo simulations have been performed to demonstrate its effectiveness in 40 nm technology node.

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