原创电阻的精度分析（Resistor Change Analysis）

 2009-7-23 21:05  1224 21 21 分类: 消费电子

在最坏情况分析中，电阻的精度应该如何考虑？
For WCA have you accounted for changes in resistance due to tolerance， aging， temperature， soldering， etc.?
(e.g.
1% resistors – 3%
5% resistors – 8%).

首先我们借鉴一下Ray Kendall， P.E.的介绍：
Linear parts
Linear parts， including resistors， capacitors， and inductors， have a single primary characteristic to model. Different factors affecting the worst case value are usually considered to be independent of one another (temperature is independent of tolerance， etc.). Statistical mathematics shows that the most realistic way to combine the effects of independent factors is by using the root-sum-square (RSS) method instead of just summing them. The RSS method can be applied by the following formula， where T represents the calculated worst case tolerance due to all factors and t1， t2， t3 etc. represent the independent tolerance factors due to initial tolerance， temperature， aging， etc.