PCB manufacturer normally provides information about PCB stackup and track geometry.
In case you need to calculate single ended or differential pair impedance on your PCB, try following links:
I use Microstrip & Stripline calculator developed by Jean Nicolle
Download the file here or directly from Jean’s website at
http://www.jnicolle.com/?page=LVDS
or try this Online PCB impedance calculator at
http://www.skottanselektronik.com/
This link also has a track maximum current calculator, crosstalk calculator and thermal via calculator.
One of the bests is this FREE Saturn PCB Design Toolkit:
http://www.saturnpcb.com/pcb_toolkit.htm
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I never thought there is such kind of calculator well technology could be really surprising sometime, I am only aware with scientific calculator, graphing calculator, an ordinary one and a mortgage calculator.
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PCB Microstrip Impedance Calculator
http://www.eeweb.com/toolbox/microstrip-impedance
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you should take a look at Saturn PCB tools. it is really interesting with tons of features next to the obvious like impedance
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Yes, Saturn is very good: http://saturnpcb.com/pcb_toolkit.htm
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Hello, I’m confused about which calculator to use for Microstrip line. According to Saturn PCB tools Z0=84.45 Ohms for the following specs:
Conductor width=10mils, Conductor Height=18mils, Base copper weight= 1 oz, Plating Thickness= 1 oz.
When I use Jean Nicolle calculator Z0=89.6 Ohms. Which is more reliable?
Thanks in advance.
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I mostly use Saturn PCB, but don’t forget, this is only approximate calculation. You always need to get the numbers from your PCB manufacturer, only they can calculate it correctly.
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Thanks for the advice. 🙂 Also can you tell me if I leave 3 times the trace width as the gap for a microstrip line will it be sufficient enough to reduce the coupling? And if the gap is more that that will a CPWG act as a microstrip?
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Bhagath, have a look at a Crosstalk calculator (e.g. Saturn PCB). Crosstalk also depends on dielectricum thickness, and some recommendations I read are to keep gap 3-5 times dielectricum thickness (not track width). Depends on your PCB and circuit. Hope it helps.
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