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    inductor gmd amd

    I am looing for the formula about inductance calculation.
    How can I calculate straight conducotr inductance ?
    Is there any inductance calculation for reference ?

    thanks a lot

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  2. #2
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    greenhouse inductance formular




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    Re: inductance calculation and formula

    If you have access to IEEE see that one(it's well known inductance calculation algorithm ) :

    IEEE TRANSACTIONS ON PARTS, HYBRIDS, AND PACKAGING, VOL. PHP-10, NO. 2, JUNE 1974
    Design of Planar Rectangular Microelectronic Inductors
    H. M. GREENHOUSE, SENIOR MEMBER, IEEE

    Also if you have access to academic library you might have this book :
    F. W. Grover, Inductance Calculations (the above paper based on this book)



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    Re: inductance calculation and formula

    Hallo,
    i have some questions on inductance determination.

    In general we can decompose L into an
    inner conductance, outer self inductance and mutual inductance.
    In case of an waveguide (or bondwire interconnect) the mutual inductance
    is neglicible if there is no other conductor.
    Therefore we have
    L = Linner + Lself

    Lself is calculated from the magnetic field between signal and ground conductor.
    Linner is calculated from the magnetic field inside the conductor.

    For high frequencies, the electric field inside the conductor decreases exponentially.
    Within the skin effect, skin depth model the following
    impedance descriptions are derived

    Z= R+jwL= (1+j) sqrt( pi * f * specific resistance * mu )

    or

    Z= R+jwL= (1+j) * specific resistance / skin depth

    This must be the inner inductance ? RIGHT ?


    Could someone comment the following statement:

    For high frequencies, there is less field inside the conductor, therefore
    the outer inductance gets more important.
    But resistance increases with frequency, due to the skin effect.

    Thanks



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    Re: inductance calculation and formula

    electr0,

    Assuming I understand your question correctly ...

    Resitance increases proportionally to the square root of frequency, but the reactance (w*L) increases in direct proportion to frequency. Even though the skin effect does decrease the inductance slightly, the reactance still dominates at higher frequencies.

    Hope this helps,

    -Wiley



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  6. #6
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    inductance calculation and formula

    the proximity effect between turns casued less field inside the turn



  7. #7
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    Re: inductance calculation and formula

    I have studied the paper,
    Design of Planar Rectangular Microelectronic Inductors
    H. M. GREENHOUSE, SENIOR MEMBER, IEEE.
    But I have some questions , AMD(Arithmetic Mean Distance)
    and GMD(Geometric Mean Distance).
    What do they mean ?
    Does any illustration explain AMD and GMD ?

    TKX



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