| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor memory device allowing reduction in the write operation by collectively determining the potentials of memory cells on the same word line. <P>SOLUTION: A semiconductor memory device collectively determines write potentials by connecting a plurality of transistors having a switching characteristic to a potential control circuit. It achieves a high-accuracy write operation and a high-accuracy read operation by continuously changing (raising or dropping) the potential stepwise, determining a desired write potential during a shift, and constantly monitoring whether the readout result data for written data is correct. It also utilizes good switching characteristics and high retention characteristics of the transistors which use an oxide semiconductor. <P>COPYRIGHT: (C)2012,JPO&INPIT |
