| 摘要 |
PURPOSE:To ensure an assured writing for the nonvolatile memory by flowing the current of not so much amount by applying the voltage featuring the slow rise to the control gate after applying the voltage to the drain of the memory transistor. CONSTITUTION:At the writing time of floating gate type nonvolatile semiconductor memory Mij containing the control gate, the voltage is applied to drain YDi of memory Mij when both writing signal DI and output Yj of Y decoder are at the high levels. After this, the slow rising pulse of high level obtained by heightening the resistance of load MOS transistor TD3i against load capacity Ci of X decder XDEC is applied to the control gate fo memory Mij. As a result, the memory transistor current is saturated at the rise of X decoder output Xi, and accodingly the channel injection is caused. Thus, the writing becomes possible without flowing so much amount of the current. |
