Copyright: 1996 - 2024
BSEE - KB3UON
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converting inductors and capacitors to microstrip - RF Cafe Forums
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but until then it is probably not worth the effort. Regardless, there are still
lots of great posts in the archive that ware worth looking at.
Below are the old forum threads, including responses to the original posts.
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Post subject: converting inductors and capacitors to microstrip
Unread postPosted: Thu Jan 06, 2005 6:03 am
Hello.I need help
about microwave office simulation program.I need to draw layout of my
circuit and i dont know how to realize the inductors and capacitors
with microstrips.For example i used a 10 nH inductor but i could not
find which substrate or W, L to use.Any link or formula about this will
help me a lot.Thanks....
Unread postPosted: Fri Jan 07, 2005 12:10 pm
Most of the closed form equations for spiral inductor are for inductances
with no ground plane influence. The influence of a ground plane will
lower the inductance due to field restriction. The equation for a square
inductor with no ground plane is:
of the inductor mm^2
N=number of turns
The total lenght of
the line in mm is calculated:
Ri=inner radius of inductor in mm
You can use the
equation to get a starting point but since microwave office has a layou
toll it may be easier to play around with simulator by adjusting the
lenght and width and determining the inductance. The inductance is calculated
L=1/(2*PI*F*Xc), where Xc is the reactance of the spiral
inductor when terminated to ground. You put this equation in microwave
office and optimize for the required inductance while placing limits
on how wide and spacing between each turn. If you have an EM simulator
( or you can go online and download the free Sonnet Lite em simulator)
you should verify the the design since the linear simulator may not
be as accurate.
Unread postPosted: Tue Mar 08, 2005 4:16 pm
can we use ADS for
reliazation of inductor into microstips?
Unread postPosted: Tue Mar 08,
2005 5:24 pm
Sun Aug 03, 2003 2:02 pm
Location: Erie, PA
I'm a little late to the game, but take a look at this page and
see if it helps.
- Kirt Blattenberger :smt024
Unread postPosted: Tue Mar
08, 2005 5:33 pm
What is the meaning of the angels
(Theta) when calculating the distributed elemenets(Capacitors, inductors)?
How does it combines with the implementation of the inductor/capacitor?
Unread postPosted: Tue Mar 08, 2005 11:39 pm
Joined: Sun Aug 03,
2003 2:02 pm
Location: Erie, PA
Theta is the electrical length (360 degrees = one wavelength) of
the transmission line at the frequency of interest.
Unread postPosted: Wed Mar 09, 2005 11:20 am
one additional comment. Because the value of inductance and capacitance
is dependent on the electrical length of the line then the effectiveness
of using this type of distributive inductance and capacitance will be
band limited. Typically, these types of distributed components are only
good for 10 to 15% band.
Unread postPosted: Wed Mar 09, 2005 3:05 pm
Thanks for your
What I really don't undersatnd is why these inductors
and capacitors are dependent on the wavelength of the transmission line?
Thanks in advance.
Unread postPosted: Wed Mar 09, 2005 5:06 pm
If you study the Smith Chart it will make sense to you.
degree short = open
91-179 degree short = capacitve
degree short = short
degree open = short
91-179 degree short = inductive
degree short = open
Unread postPosted: Thu Apr 21, 2005 3:12 am
AM A NEW USER ..CAN U TELL ME HOW REPRESENT CAPACITOR/INDUCTOR VIA MICROSTRIP?WHAT
SHOULD B ETEH DESIRED LEGTH /WIDTH IN OR TO GET THE DESIRED CAPACITOR/INDUCTOR?
WHAT ARE PADS IN ADS?
Unread postPosted: Thu Apr 21, 2005 9:08 am