| 摘要 |
An apparatus useful in determining the value of a capacitor includes a first bilateral switch for flowing a charging current through a resistive element to an initially-depleted first capacitor of known value. The first capacitor is thereby charged to the potential of a trigger reference over a resulting first time period. A second bilateral switch is provided for flowing a charging current through the same resistive element to an initially-depleted second capacitor, thereby charging it to the potential of the same trigger reference over a resulting second time period. A device such as an oscilloscope or frequency counter is used for determining these time periods and the value of the unknown second capacitor may thereupon be computed using disclosed formulas. A method for determining the value of a capacitor includes the steps of flowing a charging current through a resistive element to an initially-depleted first capacitor of known value, thereby charging this capacitor to the potential of a trigger reference over a resulting first time period. A charging current is then caused to flow through the same resistive element to an initially-depleted second capacitor for charging it to the potential of the trigger reference over a resulting second time period. The value of the second capacitor is then computed by utilizing the first time period, the second time period and the value of the first capacitor. |
