Functin of these capacitors in RF application.

Function of these capacitors in RF application.

Hi. I am trying to make an application with the PE42521, here is its page: https://www.psemi.com/products/rf-switches/pe42521 , and there is the Datasheet: www.psemi.com/pdf/datasheets/pe42521ds.pdf .

On the Datasheet, on pages 13 and 14, as far as I understand, I am supposed to include all the resistors and the capacitors of 22p. The application will run at 8 GHz, and I have been told that the capacitors are there to assure a low impedance path for the RF signal, so it won't creep into the alimentation. Is that so? And is there a way to simulate if a specific capacitor will do the job? Or will any RF capacitor of, say size 0402 (imperial) - 1005 (metric), do the job? I have tried to measure the ZIN of various capacitors in AWR Microwave Office, but I can't find capacitors with S parameters at 8 GHz, they only have info up to about 2 GHz or so.

Thank you in advance for your help.

Capacitors should have low RF impedance of course but the PCB layout is more critical in your application.
The capacitors can be selected from different manufacturers such as Murata, AVX, Johansson etc. ( Johansson is preferred regarding to my past experiences).But be careful for PCB layout and do an EM simulation with capacitors' models. That's the key point..

I have been told that the capacitors are there to assure a low impedance path for the RF signal

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Missing the point. These are bypass capacitors for power supply and control voltage. I have no idea what you want to simulate in this regard without specifications about power supply or control pin cross talk and respective s-parameters. Just try to implement an effective RF short to avoid RF leakage through these pins.

Well, I am trying to do a 1 to 8 multiplexer by lumping 7 of these together. I have done some AWR simulation with the s-parameters of the pe42521, and now I am doing the PCB. I have choosen this capacitor: https://www.mouser.es/ProductDetail...=sGAEpiMZZMvsSlwiRhF8qnany01X3VHrrYPLRARBXkk= . I hope I have choosen wisely.

The alimentation will be of 5V, and the control will come from an Arduino, with low=0V and high=3V.

Thank you for your help. I am doing the PCB with Orcad PCB Editor, and I hope it will go OK. Wish me luck