|Re: capacitors for wp34s crystal hack|
Message #6 Posted by Andrew Nikitin on 28 July 2013, 9:19 p.m.,
in response to message #4 by Jim Horn
Now I am confused.
The datasheet for crystal says 12.5pF, but the design calls for 2 x 18pF (or 2 x 15 pF, depending where I look). Is it "close enough"? Or is it accounting for all those stray capacitances that should be taken care of?
I have another question aboout capacitors. When I ordered from digikey, I typed in "0603 capacitors", it gave off million pages of results, I clicked on first that seem to fit,
I assume that 0603 is the size factor that is used in calculator in other places. However, when the package arrived, the capacitors were like 10 times smaller. They are so small, one actually fits in the gap between 2 pads. so I, probably got the wring size.
Now, I wonder, if 0603 is the right size? Or did they sent me wrong size capacitors? What is the example part number for the right form factor capacitors?