Journal of the Institute of Electronics Engineers of Korea SD (대한전자공학회논문지SD)

The Institute of Electronics and Information Engineers (대한전자공학회)
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HSPICE Macro-Model and Midpoint-Reference Generation Circuits for MRAM

MRAM용 HSPICE 마크로 모델과 midpoint reference 발생 회로에 관한 연구

  • 이승연 (이화여자대학교 정보통신학과) ;
  • 이승준 (이화여자대학교 정보통신학) ;
  • 신형순 (이화여자대학교 정보통신학과)
  • Published : 2004.08.01
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Abstract

MRAM uses magneto-resistance material as a storage element, which stores cell data as a polarization of spin in a free magnetic layer. This magneto-resistance material has hysteresis, asteroid curve at the thermal variation, and R-V characteristics for switching the data. Therefore, a macro-model which can reproduce these characteristics is required for MRAM simulation. We propose a macro-model of TMR (Tunneling Magneto Resistance) that can reproduce all of these characteristics on HSPICE. Also we propose a novel sensing scheme, which generates reference resistance having the medium value, ( $R_{H}$+ $R_{L}$)/2, for a wide range of applied voltage and present simulation results based on the HSPICE macro-model of MTJ that we have developed.d.d.

MRAM (Magneto-resistive Random Access Memory)은 자성체의 스핀 방향을 정보원으로 하는 비휘발성 메모리로 magneto-resistance 물질을 정보 저장 소자로 사용한다. 본 논문에서는 MRAM 시뮬레이션시 MTJ (Magnetic Tunneling Junction)의 hysteretic 특성, asteroid 특성, R-V 특성을 HSPICE에서 재현할 수 있는 새로운 macro-model을 제안하고 HSPICE에 적용하여 그 정확도를 검증하였다. 또한 종래의 reference cell 회로에 비하여 정확한 중간 저항 값을 유지하는 새로운 reference cell 회로를 제안하고 이를 본 논문에서 제안한 macro-model을 이용하여 검증하였다.

Keywords

References

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