

Converting Inductors and Capacitors to Microstrip  RF Cafe
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guest 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....
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Guest
Post subject: Inductor Layout 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:
L=0.85*sqrt(A)*N^(5/3) A=area of the inductor
mm^2 N=number of turns
The total lenght of the line in
mm is calculated:
Le=N*[8*Ri+d*(4*N3)] N=number of turns
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 by:
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.
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Guest Post subject: Unread postPosted: Tue Mar 08,
2005 4:16 pm
can we use ADS for reliazation of inductor
into microstips?
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Kirt Blattenberger
Post subject: Unread postPosted: Tue Mar 08, 2005 5:24 pm
Offline Site Admin User avatar
Joined: Sun Aug
03, 2003 2:02 pm Posts: 308 Location: Erie, PA Greetings:
I'm a little late to the game, but take a look at this page
and see if it helps.
http://www.rfcafe.com/references/electr
... onents.htm
 Kirt Blattenberger :smt024
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T Post subject: Unread postPosted:
Tue Mar 08, 2005 5:33 pm
Hello,
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?
Thanks,
T
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Kirt Blattenberger Post subject: Unread postPosted:
Tue Mar 08, 2005 11:39 pm Offline Site Admin User avatar
Joined: Sun Aug 03, 2003 2:02 pm Posts: 308 Location:
Erie, PA Greetings T:
Theta is the electrical length
(360 degrees = one wavelength) of the transmission line at the frequency
of interest.
 Kirt Blattenberger :smt024
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Guest Post subject: Unread postPosted:
Wed Mar 09, 2005 11:20 am
Just 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.
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T Post subject: Unread postPosted:
Wed Mar 09, 2005 3:05 pm
Thanks for your reply Kirt!
What I really don't undersatnd is why these inductors and capacitors
are dependent on the wavelength of the transmission line?
Thanks in advance.
 T
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Rod
Post subject: Unread postPosted: Wed Mar 09, 2005 5:06 pm
If you study the Smith Chart it will make sense to you.
90 degree short = open
91179 degree short = capacitve
180 degree short = short
_____________________________
90 degree open = short
91179 degree short = inductive
180 degree short = open
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MICRO
Post subject: MICROSTRIP Unread postPosted: Thu Apr 21, 2005
3:12 am
I 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?
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Guest Post subject: Unread postPosted:
Thu Apr 21, 2005 9:08 am
Read a book!
Posted 11/12/2012



