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Typical Values for Parasitic

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Mechatrommer:
can someone advice on "typical" parasitic capacitance, inductance and resistance values for "typical" application such as:
1) solderless breadboard
2) x distance of pcb track and width
any parasitic relation to track dimension and distance between adjacent track?

i mean typical is general, good enough estimation during circuit design/simulation.
and "typical" can means the things you've encountered incl it application.
whatever value will do, i just want to get a rough picture. thanx.

Mechatrommer:
btw, to be more precise, actually i want to include parasitic model in my future circuit simulation. here is my basic model, the values are just blind guess. so c&c welcomed.
(note: coupler usually means ground, but can be connected to adjacent transmission line)

vk6zgo:
Back in the valve(vacuum tube)/discrete component days,the figure commonly quoted was 20pf.

Even though our components are many times smaller,most of the dielectric was air,now it is PCB material,so it may still be a good figure to start

from.

VK6ZGO

Zero999:
 At high frequencies you can't use lumped elements, the PCB traces must be treated as transmission lines.

jahonen:
I tend nowadays always think PCB traces as transmission lines since that won't give misleading results for any situation unlike the lumped element assumption. Although it must be noted that this is sensible solution only if the traces have some reasonable geometry, for which the impedance can be calculated (like trace near the ground plane so that width of the trace is about same or more than height from the ground plane), so this does not apply if you have traces in the pcb with no ground plane in opposite side. But then, you generally can't use that kind of "cheap" geometry if you have concerns about fast edge rates or high frequencies.

Regards,
Janne

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