| 安规007 |
2011-04-28 11:53 |
The relevant time constant is the product of the effective capacitance in microfarads and the
effective discharge resistance in megohms. If it is difficult to determine the effective
capacitance and resistance values, a measurement of voltage decay at the point of external
disconnection can be used. When conducting the voltage decay measurement, the result is
referred to an instrument having an input impedance consisting of a resistance of
100 MΩ ± 5 MΩ in parallel with an input capacitance of 20 pF ± 5 pF.
从标准的内容来说，确实是要求100 MΩ ± 5 MΩ 阻抗，但是我个人觉得阻抗越大，分流就越小，测到的数据就越接近真实情况。但标准不知道是怎么考虑的，为什么不在100M前面加上at least 之类的字眼。 |
|