Need plugins of Ansoft HFSS to compute Q of spiral inductor

[mike_bihan]

: Need plugins of Ansoft HFSS to compute Q of spiral inductor, can any people offer hand?

 

[BigBoss]

really neccesary ?

Compute S-parameters and convert Touchstone format. Put them in a black box in a linear simulator and make a s-parameters simulation with second port short circuited. After this simulation , find Z-prameter and calculate real and imaginary part of the black box from S11 ( or they are automatically calculated ) and then ..

imag( Z11 )
Inducance = ----------------
2.pi.freq

imag ( Z11)
Q =---------------
real ( Z11)

I think it's clear ? Because I use this method within ADS and works well..

Good Luck

 

[STD]

really neccesary ?

Compute S-parameters and convert Touchstone format. Put them in a black box in a linear simulator and make a s-parameters simulation with second port short circuited.


Why second port should be short circuited to get Z pars?

 

[flyhigh]

Re: Need plugins of Ansoft HFSS to compute Q of spiral induc

Hi,

I think I can answer that question. The second port sould be short circuited to avoid loading of your inductor with 50Ohm impedance of the port. This 50Ohm will be included in your Q otherwise. Hope this helps

flyhigh

 

[STD]

flyhigh,
This Q factor is named unloaded Q(Qu)?Thanks.

STD