| 摘要 |
PURPOSE:To obtain a semiconductor memory device where the write operation is high-speed and the read operation is stable, by making transistors different in threshold of a voltage generation circuit conductive to set the voltage of the word line to different values for information read and write. CONSTITUTION:By the write command signal for information write, MOSFET23 becomes conductive, and wordline 10 selected by the input of the address signal to a decoder becomes high-level. Then, by the read command signal, MOSFET20 becomes conductive, and line 10 becomes high-level similarly. However, the high-level voltage applied to line 10 for write is larger than that for read because MOSFET23 and MOSFET20 are different in threshold. Consequently, gates of MOSFET6 and MOSFET7 are biased by a positive potential lower than that for write at a read time, and resistance for conduction of FET6 and FET7 becomes large for read and becomes small for write. As the result, a semiconductor memory device is obtained where the write operation is high-speed and the read operation is stable. |
