JP2567177B

PURPOSE:To unnecessitate a register storing information transiently and to integrate high by having one piece of a spare cell par column in addition to a data storing memory cell and rewriting reading information to the cell in the state of not in use. CONSTITUTION:Word lines WLO are made an ON state successively, the storing information of the capacitors C1-C4 of a cell MCO are read to a bit line BL. Then, the word lines WLO are made an OFF state successively, 4 bit information iS rewritten to the capacitors C1-C4 of the cell MCn in the state of not in use of the same column. Further, the 4 bit information of the cell NC1 is read to the bit line BL and rewritten to the cell MCO. By repeating this operation successively, a block data stored to (n) pieces of the cell are read and rewritten to (n) pieces of the cell containing one piece of the cell in the state of not in use. Thus, a register storing transiently the information read time sequentially is unnecessitated and the high integration is performed.