Conference Paper

A 64Mb MRAM with clamped-reference and adequate-reference schemes

Toshiba, Yokohama, Japan
DOI: 10.1109/ISSCC.2010.5433948 Conference: Solid-State Circuits Conference Digest of Technical Papers (ISSCC), 2010 IEEE International
Source: IEEE Xplore

ABSTRACT A 64 Mb spin-transfer-torque MRAM in 65 nm CMOS is developed. A 47 mm2 die uses a 0.3584 ¿m2 cell with a perpendicular-TMR device. To achieve read-disturb immunity for the reference cell, a clamped-reference scheme is adopted. An adequate-reference scheme is implemented to suppress read-margin degradation due to the resistance variation of reference cells.

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