H. Koike, S. Miura, H. Honjo, Tosinari Watanabe, Hideo Sato, S. Sato, T. Nasuno, Y. Noguchi, M. Yasuhira, T. Tanigawa, M. Muraguchi, M. Niwa, Kenchi Ito, S. Ikeda, H. Ohno, T. Endoh
{"title":"1T1MTJ STT-MRAM Cell Array Design with an Adaptive Reference Voltage Generator for Improving Device Variation Tolerance","authors":"H. Koike, S. Miura, H. Honjo, Tosinari Watanabe, Hideo Sato, S. Sato, T. Nasuno, Y. Noguchi, M. Yasuhira, T. Tanigawa, M. Muraguchi, M. Niwa, Kenchi Ito, S. Ikeda, H. Ohno, T. Endoh","doi":"10.1109/IMW.2015.7150264","DOIUrl":null,"url":null,"abstract":"A device-variation-tolerant spin-transfer-torque magnetic random access memory (STT-MRAM) cell array design with a high-signal-margin reference generator circuit was developed to create high-density 1T1MTJ STT-MRAMs. To realize an appropriate STT-MRAM design, fluctuations in the memory cell characteristics were first measured using a 1-kbit STT-MRAM test chip. Based on these measurements, a reference generator and an STT-MRAM cell array architecture were proposed. This cell array was evaluated in terms of the signal margin for read operation and its tolerance to device variation by means of Monte-Carlo SPICE circuit simulations. The proposed design enables a 50% improvement in the signal margin compared with the conventional cell array circuit.","PeriodicalId":107437,"journal":{"name":"2015 IEEE International Memory Workshop (IMW)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2015-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"16","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"2015 IEEE International Memory Workshop (IMW)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/IMW.2015.7150264","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 16
Abstract
A device-variation-tolerant spin-transfer-torque magnetic random access memory (STT-MRAM) cell array design with a high-signal-margin reference generator circuit was developed to create high-density 1T1MTJ STT-MRAMs. To realize an appropriate STT-MRAM design, fluctuations in the memory cell characteristics were first measured using a 1-kbit STT-MRAM test chip. Based on these measurements, a reference generator and an STT-MRAM cell array architecture were proposed. This cell array was evaluated in terms of the signal margin for read operation and its tolerance to device variation by means of Monte-Carlo SPICE circuit simulations. The proposed design enables a 50% improvement in the signal margin compared with the conventional cell array circuit.