| 摘要 |
PURPOSE:To facilitate the design of a dynamic memory by providing a drive system to store the electric charge in a dummy cell before the precharging of a bit line is started and therefore deciding the capacity ratio between the dummy cell and a memory cell just from the area ratio between both cells. CONSTITUTION:In a precharge mode, the bit lines BL and -BL are precharged up to the level of the power supply voltage since the level of an internal clock phi0 rises higher than the power supply voltage and then exceeds the threshold voltage of a MOS transistor TR and therefore MOS TRs Q1, Q2 and Q9 are turned on. In an action mode the precharging is through since the clock phi0 is set at an L level and the Trs Q1-Q9 are turned off. Then a word line phiw0, for example, out of those word lines phiw0-phiwm and phiwm+1-phiwn is set at an H level by a row decoder. Thus a MOS TRQ5 is turned on and only a memory cell Mc0 is connected to the bit line BL among those memory cells Mc0-Mcm and Mcm+1-Mcn. |
