| 摘要 |
PURPOSE:To switch very stably various electronic circuits to a resetting state at the application of power supply by providing a capacitor and a switching element of which the operating state is switched at the charging and the discharging of the capacitor. CONSTITUTION:A transistor(TR)Q3 is turned off while the capacitor C1 is increased to a desired charging voltage at the application of a power supply +Vcc. An FF circuit (not shown) is reset by a collector signal of the TRQ3. Then, the TRQ3 is operated into ON-state after the set time and the reset operation is released. Thus, the reset time is set freely and very stable starting operation is attained. Since an electric charge charged in the capacitor C1 is discharged via diodes D1, D2 even if the +Vcc power supply voltage is fluctuated, the TRQ3 is held surely to OFF-state, this is not changed on ON-state or OFF-state and used surely for the release of reset. |
