| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a semiconductor memory device reading stable data without being affected by a characteristic of a memory cell caused by dispersion of process, mainly, variation of threshold voltage. SOLUTION: An activation signal generating circuit 1 constituting of a comparator CMP1 being a first comparator, a comparator CMP2 being a second comparator, a NOR gate NOR1, an inverter INV1, and an inverter INV2 is connected to a terminal to which a sense amplifier activation signal SAEN of a sense amplifier SA1 is inputted. Also, a comparator is applied to the comparator CMP1 and the comparator CMP2 of the activation signal generating circuit 1. The comparator performs comparison operation with operation input having potential difference being equal to potential difference between + input and -input required for performing normal amplifying operation by the sense amplifier SA1 or being larger potential difference. After the sense amplifier reaches difference voltage being able to normally operate, read-out of erroneous data is prevented by activating the sense amplifier.</p> |
