The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
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An Equalizing Algorithm for Cell-to-Cell Interference Reduction in MLC NAND Flash Memory

MLC NAND 플래시 메모리의 셀 간 간섭현상 감소를 위한 등화기 알고리즘

  • 김두환 (충북대학교 전자정보대학 정보통신공학과) ;
  • 이상진 (충북대학교 전자정보대학 정보통신공학과) ;
  • 남기훈 (충북대학교 전자정보대학 전기공학과) ;
  • 김시호 (충북대학교 전자정보대학 전기공학과) ;
  • 조경록 (충북대학교 전자정보대학 정보통신공학과)
  • Received : 2010.04.23
  • Accepted : 2010.05.12
  • Published : 2010.06.01
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Abstract

This paper presents an equalizer reducing CCI(cell-to-cell interference) in MLC NAND flash memory. High growth of the flash memory market has been driven by two combined technological efforts that are an aggressive scaling technique which doubles the memory density every year and the introduction of MLC(multi level cell) technology. Therefore, the CCI is a critical factor which affects occurring data errors in cells. We introduced an equation of CCI model and designed an equalizer reducing CCI based on the proposed equation. In the model, we have been considered the floating gate capacitance coupling effect, the direct field effect, and programming methods of the MLC NAND flash memory. Also we design and verify the proposed equalizer using Matlab. As the simulation result, the error correction ratio of the equalizer shows about 20% under 20nm NAND process where the memory channel model has serious CCI.

Keywords

References

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