A 64Mb MRAM with Clamped-Reference and Adequate-Reference Schemes

📋 论文概要

本文提出了一种64Mb MRAM，采用钳位参考和适当参考方案，通过电流镜和复制存储单元生成稳定的参考电压，解决了MRAM读取过程中参考电压波动和可靠性问题。

💡 主要创新点

• 提出钳位参考系统，利用电流镜和复制存储单元生成稳定的钳位电压，优化读取电流。
• 提出适当参考方案，进一步提高读取裕度和可靠性。
• 实现了64Mb容量的MRAM，验证了所提方案的有效性。

🏷 关键词

📄 原文摘要

Takafumi Shimizu, Yoshiaki Asao, Takeshi Kajiyama, Masayoshi Iwayama, Kuniaki Sugiura, Sumio Ikegawa, Tatsuya Kishi, Tadashi Kai, Minoru Amano, Naoharu Shimomura, Hiroaki Yoda, Yohji Watanabe The voltage generators for the clamped-reference system are designed utilizing the current mirror circuitry and replica memory cells. By adjusting the constant current source (Iread), the “high” state cell read current (I”H”) is set at optimal level. The VCLMP voltage, transferred to the voltage clamper for selected BL, is generated by using “high” state replica memory cell. The VREF voltage for reference BL is derived form VCLMP. The reference current Iref(=(I”H”+I”L”)/2) is obtained by combining “high” and “low” state replica cells. The Iref is converted to VREF by a diode-connected NMOS and a “low” state replica cell. Toshiba, Yokohama, Japan In order to realize a sub-Giga bit scale NVRAM, the novel MRAM based on the

👥 作者与机构

Kenji Tsuchida, Tsuneo Inaba, Katsuyuki Fujita, Yoshihiro Ueda,