| 摘要 |
PURPOSE:To reduce a current consumption at the time of performing an access to one column by making the number of data lines connected with a column line at the time of a mode in which the access to the plural line column lines is simultaneously attained by controlling a connecting means, different from that at the time of the mode in which the access to one column line is attained. CONSTITUTION:At the time of a block write mode, a block write signal BLW is turned to 1, and control signals Y0 and Y1 for connection outputted from a partial column decoder 10 are turned to 1, so that the decoder 10 and the connecting means can be formed. For example, transfer, gate transistors T0-T4 are turned ON through a column decoder CDO or the like by plural column selecting lines CSLO and CSL1, so that four column lines can be connected with four data lines DQ0-DQ3. In the same way, in one bit mode in which one column line is selected, only one of the selecting lines CSL0 and CSL1 is selected, so that two data lines can be connected with one column line, and the current consumption at the time of one bit read and write can be decreased. |
