Can we use the low frequency capacitors and resistors for up to 3 GHz RF frequency?

[7rots51]

Can we use the capacitors(smd) and resistors(smd 0805,smaller) that we use in low frequency (under 100mhz)circuits for up to 3GHZ rf frequency?
If no,what types is suitable?

 

[pisoiu]

RF res,cap?

As far as I know, if the working frequency is under the series resonant frequency of the component, then there is no problem. Unfortunately, not all the manufacturers offers informations about SRF. For example, take a look at Kemet spice, , this manufacturer offers nice graphs with impedance vs freq. for their caps. I use regular 0603 and 0402 at 2,5GHz with no problems.

/pisoiu

 

[kella]

RF res,cap?

in the @DS component library none of the capacitors have SRF more than 6-7 GHz. How to design a capcitor which has SRF more than 10 GHz or what can be alternate to this?

thanks
/k

 

[pisoiu]

RF res,cap?

The highest SRF I've seen at the components I use is 10GHz, for a 0402 type inductor. Beyond this....microstrip?

/pisoiu

 

[flatulent]

Re: RF res,cap?

Can you make your own capacitors? One type is thin filaments in an interdigital structure. I have also seen parallel plates, air dielectric, types soldered perpendicular to the PC foil. This is really a short open circuited transmission lines.