| 摘要 |
PURPOSE:To make the operation stable, by producing a reset pulse independently of the leading time constant of the power supply voltage at the application of power supply. CONSTITUTION:If the leading speed of the power supply voltage VPOW is steep at the application of power supply, a voltage Vin at an input gate 10 is applied to the voltage Vin as a reset pulse while the voltage having a leading time constant consisting of resistance values of R1-R3 of resistors 7, 8, 10-2 and a capacitance of a capacitor 9 reaches a threshold voltage Vs in a time T1. If the leading of the power supply VPOW is slow, the voltage Vin at the input gate 10 is applied to the voltage Vin as a reset pulse while a voltage determined with a forward voltage VF of diodes 3-5, 10-1 reaches a threshold voltage Vs in a time T2. Thus, the leading time constant can not be taken into account. |
