| 摘要 |
<p>PURPOSE:To obtain a power-ON reset pulse which has a sufficient amplitude even when the rising time of a source voltage is long by simple constitution. CONSTITUTION:A 1st P type MOS transistor(TR) 1 whose gate is connected to the source and a 2nd P type MOS TR 2 whose gate is grounded are connected in series and the power-ON reset circuit is connected to the connection point to which the 1st and 2nd seriesconnected P type MOS TRs 1 and 2 and a capacitor 3 are connected. Even if the rising time of the source voltage VDD is long, the voltage is applied to the drain of the 2nd P type MOS TR 2 when dropping by the threshold voltage of the 1st P type TR 1, so an ON state is entered when the source voltage becomes higher than usual and the power-ON reset pulse has the sufficient amplitude.</p> |
