问个关于电感Q的问题，困扰已久

dj_max

电感Q=w*L/Rs，基本都这么算的吧
可是看了些电感产品，感觉不对啊，比如：
一个82nH电感，厂家提供的信息是：最小Q=50 at 500MHz，最大DC resistance=0.42 ohms。
如果按上面那个式子算，500MHz下最小Q=600+，这个算出来的值一看就觉得不对，但也不知道错在哪里？请大侠指教

fuyibin

电感Q=w*L/Rs，基本都这么算的吧
可是看了些电感产品，感觉不对啊，比如：
一个82nH电感，厂家提供的信息是：最小Q=50 at 500MHz，最大DC resistance=0.42 ohms。
如果按上面那个式子算，500MHz下最小Q=600+，这个 ...
dj_max 发表于 2009-11-10 12:40

                               
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the resistance of inductance is 0.42ohm at dc frequency.
when the frequency increases, the resistance of inductance will increase due to the skin effect. so the Q is much smaller than your calculation due to the loss at high frequency.

northfish

The Q equation is based on a simple L-Rs model, while all actual inductors are much more complex than that.  In addition to the skin effect mentioned above, parasitic capacitance, eddy current and other effects may kick in and reduce your Q.

jiangyanjin

Thank you!

1714wangyong

goooooooooooooood

Arvinliu

受教啦

吾老公

高频的Q有很多影响，比如eddy current，skin effect，不能用dc resistance算