| 摘要 |
PURPOSE:To reduce a drop in readout signal voltage due to the electrostatic capacity between bit lines and to prevent an error in reading operation by crossing two bit lines of alternate bit line couples in the middle of bit line couples. CONSTITUTION:Two-bit lines constituting alternate bit line couples (ELla, -BL1a), (BL3a, -BL3a) - cross each other at a halfway point. In this constitution, the bit line -BL1a, for example, has electrostatic capacity 1/2C1 between said line the adjacent bit line BLla, 1/2C2 between said line the adjacent bit line BL2, and 1/2C3 between -BL1a and the ground at the upper half part from the center part CP. At the lower half part in a figure with respect to the center part CP, only the electrostatic capacity 1/2C1 between the bit line -BL1a and bit line BL1a is important and the bit lines -BL1a and BL2 are separate from each other, so the electrostatic capacity can be ignored.
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