Switch power of high frequency is serious electromagnetic interference (EMI) source, so EMI source filter usually should be added in switch power.

高频开关电源是严重的电磁干扰源，很多情况下需对其安装emi电源滤波器。

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The chip is highly integrated, on-chip integration of the design filter resistors and capacitors needed in the application of only very few external devices can be easily constitute a source filter.

这种芯片集成度高，片内集成了设计滤波器所需的电阻和电容，在应用中只需极少数外部器件就可以很方便地构成一个源滤波器。

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Connect Intake-tube with intake-tube of air filter of the rewinder, then get through entering power source.

将进气管与复卷机空气过滤器的进气管相连，然后进入电源。

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In humans the vocal tract acts as a filter on the sound from the source, and the "source-filter theory" held that the separate, fine control of the vocal tract to be the product of a long evolution in the development of the subtleties of speech.

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How does this source of information filter down to practice?

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