| 摘要 |
A charging and discharging integration circuit packed in an IC package is disclosed. A charging current is transferred from a constant voltage source to a capacitor element through a first external terminal and a charging resistor placed outside the IC package. The capacitor element is grounded. A driving current is transferred from the constant voltage source to a current limit driving circuit through a discharging resistor placed outside the IC package through first and second external terminals. A discharging current composed of the charging current and a capacitor current flowing from the capacitor element passes a current limiting circuit through a third external terminal. The driving and discharging current are discharged to the earth through a fourth external terminal. The driving current is controlled by a comparing circuit in which a voltage of the driving current is almost equalized with a capacitor voltage of the capacitor element, so that a value of the driving current is proportional to a voltage difference between the constant voltage source and the capacitor element. The discharging current is adjusted by the current limit driving circuit in proportion to tile driving current, so that the value of the driving current is proportional to the voltage difference.
|
