| 摘要 |
PURPOSE:To speed up operation, by using three or more comparison potential values by sense amplifiers and discriminating an output from the sense amplifier in accordance with the charge/discharge of row/line potential. CONSTITUTION:Comparison potential values V1, V2, V3 are set up on the basis of the potential of a node S as shown in the figure. When the potentia of S>V1, A=''1'' and A'=''0'' are set up in the sense amplifier. To other sense amplifiers, the same manner is applied, If S>V1 when the node S is turned from ''0'' to ''1'', ''1'' is detected and outputted. If S<V3 when S is turned from ''1'' to ''0'', ''0'' is detected. Consequently, the time crossing the comparison potential with the potential of S is increased, the speed of the operation can be increased. Even if the node S is discharged to ''0'' at a point exceeding the V1, the potential is discriminated as ''0'' if reducing lower than the V2. When the node S exceeds V2 once and then drops lower than the V2 again, high speed operation is avilable even if the operation shown by the figure is generated because the V2 level exists near the node S by providing the potential V2. |
