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  1. #1
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    Decoupling capacitor value

    Hi

    how do i choose the decoupling capacitor for DC bias line to a IC.
    i think 0.1uF and 10uF are common one.
    But what if i have a cellular switch IC which operating in different cellular band lets say 800MHz and 2100MHz.
    how do i choose the value of the decoupling capacitor for the dc bias line for the cellular switch IC so that i wanted to attenuated or bypass any high frequency noise , 800MHz and 2100 Mhz in the dc line.

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  2. #2
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    Re: Decoupling capacitor value

    Follow the manufacturer's recommendations
    In general for decoupling frequence > 1GHz is good choice use 100pF NPO, smal sice for example 0402. see Picture.
    I recommend to read
    Decoupling Techniques from AD

    Click image for larger version. 

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  3. #3
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    Re: Decoupling capacitor value

    a feedthrough type of decoupling capacitor will bypass the noise in DC line.



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  4. #4
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    Re: Decoupling capacitor value

    thx for the input. any formula on selecting the value?
    how bout for cellular LB 700-900Mhz range or WIGI 2.4Ghz/5GHz.

    thanks



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