planar inductor design

Hi,
I'm interested in design of planar inductors on FR4.
I need it because I'd like to develop matching circuits with planar passive components instead of chip components.
The problem is that if you want to define a given value of inductance by means of an analytical process it's too difficult.
My question is: Is there anyone who knows if exists some program which given a value of inductance determines the geometry dimensions of the planar inductor automatically?
What's the fastest way to implement a planar inductor with a predefined geometry given a value of inductance?
I don't think that implementing a casual structure in HFSS and starting to simulate to extract L value would be an intelligent approach...
Thanks in adv..

hi,
i think there is some software from UCberkely. (sorry forgot the name). Or you can see Thomos lee's book
cv

Added after 2 minutes:

i think that softwares name is ASITIC

Hi,
i don,t think it is difficult doing it with HFSS.
alternatives are:
ADS momentum.
Ansoft designer.

I know two progremmes, UCBerkley ASITIC....OEA International SPIRAL...products helps you to solve your problem...

www.oea.com/document/spiral.pdf


---manju---

Not sure if this is what your talking about, but a simple calculator will do that for you. shorted stubs is
XL = Zo (of trace) * ( Tan *wavelenght-in-degrees).

This math is good for <90 degrees.
Open stubs exist as inductors only after 90 degrees (just subtract 90 degrees from the equation).
Normally, I use less than 90 because of the size of the stubs.

Hi, ifelix:

The SpiralSyn in IE3DLibrary from Zeland will achieve what you want: Given the L value, SpiralSyn will synthesize the dimensions of the spiral. It is driven by full-wave EM simulation engine. You can give it a try (www.zeland.com). I am from Zeland. Regards.