| 摘要 |
PURPOSE:To attain stable read-write by providing a delay circuit, reset/set flip- flop circuit and a read/write control circuit, and using the pulse edge of an R/W control pulse, and generating a proper pulse suitable for the R/W control at the inside. CONSTITUTION:R/W control signals are inputted from a terminal 20; one is inputted to a reset terminal 22 of the reset/set flip-flop (RS-F/F) circuit 25 via a delay circuit 21, and the other is inputted to a set terminal 26 of the RS-F/F25 not through the delay circuit and they are outputted from terminals 23 and 24 as true logic signal and complementary logic signal. Since a voltage corresponding to an input threshold voltage VTH of the RS-F/F circuit 25 is applied at a point P at a set input terminal 26 of the RS-F/F circuit 25, the voltage waveform set by the RS-F/F circuit 25 rises at the point P and falls down at a point Q. Since the pulse width depends on a delay time (d) of the delay circuit 21, the width is selected optionally by adjusting the delay time. |
