基于一种NAND闪存页缓存器设计的C/F读取算法研究  

Research on Coarse/Fine Read Algorithm Based on a NAND Flash Page Buffer Design

作　　者：陈珂[1,2] 杜智超 叶松[1] 王颀 霍宗亮[2,3] CHEN Ke;DU Zhi-chao;YE Song;WANG Qi;HUO Zong-liang(College of Communication Engineering,Chengdu University of Information Technology,Sichuan,chengdu 610225,China;Institute of Microelectronics of Chinese Academy of Sciences,Beijing 100029,China;School of Microelectronics,University of Chinese Academy of Sciences,Beijing 100029,China)

机构地区：[1]成都信息工程大学通信工程学院,四川成都610225 [2]中国科学院微电子研究所,北京100029 [3]中国科学院大学微电子学院,北京100029

出　　处：《电子学报》2018年第11期2619-2625,共7页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61474137);国家自然科学基金(No.61404168)

摘　　要：为减小共源线噪声对NAND闪存读可靠性的影响,设计了一种可实现C/F(Coarse/Fine)读取操作的页缓存器电路,并设计实现了适用于此电路的C/F读取算法,显著减小了共源线噪声.该算法通过两次子读感应读取存储单元,在第一次子读感应中分辨出阈值电压较低的存储单元并标记在页缓存器中,使其不再进行第二次子读感应,从而减小共源线噪声引起的阈值偏移.电路仿真计算表明,该支持C/F读取算法的页缓存器结构能够减小阈值偏移至少495. 6mV,有效提高了NAND闪存读操作的精确性.To reduce the effect of the common source line noise in read operation of NAND Flash Memory,a page buffer circuit which can realize the coarse/fine read operation is proposed and a C/F read algorithm suitable for the page buffer circuit is introduced and implemented which can reduce the common source line noise significantly.There are two sub-read operations in the algorithm,the purpose of the first sub-read operation is to distinguish the cells with lower threshold voltage and mark them in page buffer circuit.These cells are no longer sensed in the second sub-read operation.As a result,the threshold voltage shift caused by the common source line noise is suppressed.The circuit simulation results show that the page buffer structure which supports the C/F read algorithm can reduce the shift of the threshold distribution more than 495.6mV and the read accuracy of NAND Flash Memory is greatly improved.

关 键 词：NAND闪存 多值存储单元 页缓存器 Coarse/Fine读取算法 读可靠度 

分 类 号：TP333.52[自动化与计算机技术—计算机系统结构]