| 摘要 |
<p>PURPOSE:To facilitate an easy program verifying job immediately after a data writing action is through by securing a state where a large current can be flown toward a DC power supply from a word line in a program verifying mode. CONSTITUTION:An (n) channel transistor TRT8 having the threshold voltage set at 0 is connected in parallel to a depression type TRT3. In a program verifying mode the gate potentials (a) and (b) of the TR T6 and T5 are set at OV and Vcc respectively. Thus the TR T6 T5 are turned off and on respectively. In this case, the electric charge stored to a word line Wn is flown to the DC power supply Vcc through a parallel circuit of the TR T5, T3 and T8. Thus a large current can be supplied to the Vcc side from the word line and therefore the potential of the word line can be reduced down surely to the Vcc within a prescribed period of time after the data writing is over despite a small size of the TR T3. Then a program verifying job is possible immediately.</p> |
