Reviving an old topic to pose some new questions. (Nice eh?
)
I'm using an ATC600S cap (47pF, 0603 size) as a DC-block at the input and output of a switch (operating between 3-4 GHz). I've been trying to read up on ESR, reactance, resonant frequencies etc etc.. but I'm having trouble connecting the dots.
See, I need the capacitor to have very good (low) Insertion Loss. And it IS good. But I need to justify this by some theory.
Below is a monologue by me, where I pose some questions that I may or may not answer correctly. Id very much like it if someone could give me any input regarding this
ESR:
So, the ESR is a resistance in series with the capacitance, caused by the resistive materials (dielectric, terminals etc). Am I getting this right? And, the larger ESR, the more power the capacitor will dissipate, yeah? Which leads to more heat generated, which will increase the noise figure in my system.
I can't imagine anything other than that this ESR effect would be baked in the final result that is the Sparameters of the device, am I right? And since S21 is the Insertion Loss, I would be correct if I calculate the Noise Figure by using this data?
Monologue finished.
Resonant Frequencies.
What is the difference between Series Resonance and Parallel resonance? The frequency of full resonance is easily spotted by looking at the S-parameters, but how do I know if its one or the other?
There is resonance at approximately 4.5 GHz in the ATC600S470, this should be good right, since my system operates between 3-4.. Or is it dangerously close? I wouldnt know..
Many thanks to whoever manages to get though this post and answers
Best Regards,
Alex