摘要 |
A first normal bit and source lines are connected to a first memory cell. Second normal bit and source lines are connected to a second memory cell. A first column switch connects one of the first and second normal bit lines to a first global bit line. A second column switch connects one of the first and second normal source lines to a first global source line. A first reference bit and source lines are connected to a third memory cell. A third column switch connects the first reference bit line to a second global bit line. A fourth column switch connects the first reference source line to the first global source line. A sense amplifier is connected to the first and second global bit lines, and reads data stored in one of the first and second memory cells. |