polelow

My Nuhertz license file is frozen. Can someone generate a 5th order low pass filter for me? It shouldn't pass anything above 2.5GHz. If able please make with realistic cap and inductor values. No transfer function just the physical schematic drawing generated by the SW. Kind Regards.

You can do it by yourself.
Look at www.aade.com and download the filter design program for free.
It′s for passive RLC structures of any order.

Some of the cap and inductor values are not realistic. How do you work around this? I tried changing the value of one cap but I dont see a change in the other part values........

very nice site
thank you LvW

As for each LC circuit you are free to scale all elements with a suitable factor by yourself.

The problem I am having is that the tool is designing a filter with 4nH inductor and 3pf capacitors. Well if I place this filter on a board dont I have to consider stray capacitance and inductance? So a 3pf conductor will behave as maybe a 7pF which will change my filter performance? If I increase any of the values it appears that my cutoff is lower in frequency. So how do I increase the value of my L's and C's but maintain the same filter characterestics? Do I have to use a different filter?

If you increase/decrease the values of both the L′s and the C′s, of course, the transfer function changes.
Remember a simple voltage divider: it does not matter if both resistors are 100 ohms/200 ohms or 1k/2k. That means: The IMPEDANCE level of all parts has to be changed. Back to basics !
In your case, that means that the capacitice/inductive IMPEDANCE has to be altered:
Increas C by the same amount as L is decreased and vice versa !
The same applies to input/output resistors.