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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.

其中可以把Tol认为是标称的精度，温度误差为独立的误差，其他的误差都是和制造和使用环境有关的，属于不确定因素
下面来看一个例子：

因此我们在预计，实际的误差最大应该是多少，有哪些部分是可以通过校验去除的，有哪些可能短时间内变化，有哪些在长期变化。

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