SEMICONDUCTOR MEMORY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor memory device which avoids the increase of area and complex control, can deal with the size structure variable parametric RAM and allows easy and exact control and the reduction of current consumption at the time of writing operation. SOLUTION: A control circuit 1a detects the readout data of the dummy memory cell DMC arranged in the cell array and makes the enable signal EN inactive to control the finish of the readout operation at the time of readout. Similarly at the time of writing, it inactivates the enable signal EN based on the output of the dummy memory cell DMC to control the finish of the writing operation. By this, the installation of an exclusive pulse generator is made unnecessary and the increase of area and complex control is avoided. And since even the parametric RAM of variable size constitution can produce activated pulses in accordance with its delay, control is kept easy and exact.