| 摘要 |
<p>PURPOSE:To prevent the malfunction of reset by providing a PNP transistor(TR) between a resistor and a capacitor and charging a capacitor with a base current from the PNP TR. CONSTITUTION:A PNP TR Q1 is provided between a resistor R1 and a capacitor C1. A current supplied at the application of power is inputted to the PNP TR Q1 via the resistor R1 and a charge current flows from the base of the PNP TR Q1 to the capacitor C1. In this case, the TR Q1 acts like a resistor having a large resistance and it is equivalent to connect a resistor having the resistance of a multiple of beta, where beta is a current multiple factor of the PNP TR Q1. Thus, the time constant is extended by the increased resistance to slow down the charge speed of the capacitor C1, then the pulse width of the resetting signal is increased. Then the malfunction of reset is prevented.</p> |
