公开(公告)号：US06650568B2

公开(公告)日：2003-11-18

申请号：US10038828

申请日：2002-01-08

申请人： Mitsuteru Iijima

发明人： Mitsuteru Iijima

IPC分类号： G11C1604

CPC分类号： G11C16/28 ,  G11C8/14 ,  G11C11/5621 ,  G11C11/5642 ,  G11C11/5671 ,  G11C11/5692 ,  G11C16/0475 ,  G11C16/08 ,  G11C2211/5634

摘要： Memory cell currents flowing through memory cells in reading data are compared with reference currents that are set in accordance with the wiring widths of word lines connected to these memory cells. The logic levels of data retained in the memory cells are detected depending on whether larger or smaller the memory cell currents are than the reference currents. Setting a plurality of reference currents for every wiring-width of word lines allows the reference currents to be set at optimum values for each memory cell having different gate widths. Since the reference currents are set according to the characteristic of memory cells, read margins improve for enhanced reliability in read operations.

摘要翻译： 将读取数据中流过存储单元的存储单元电流与根据连接到这些存储单元的字线的布线宽度设置的参考电流进行比较。 根据存储器单元电流是否比参考电流更大或更小来检测保存在存储器单元中的数据的逻辑电平。 为字线的每个布线宽度设置多个参考电流允许将参考电流设置为具有不同栅极宽度的每个存储单元的最佳值。 由于参考电流根据存储单元的特性设置，所以读取余量提高了读操作的可靠性。