J
Joel Koltner
- Jan 1, 1970
- 0
Has anyone here used the type of RF relay that's packaged like this one:
http://www.rfrelaystore.com/productdesc.php?pid=RDT-2P1D6 ? If you look at
the mounting drawing link on that page
(http://www.rfrelaystore.com/pdf/mounting/1500901.PDF), the idea is that your
hog out a pocket on your PCB for the relay to sit in and your microstrip
traces contact the relay terminals clearnly. However, shouldn't I be worried
that there isn't really a ground connector between the relay and the PCB's
ground plane that I can see? At 6GHz you're looking at wavelengths on the
order of an inch on a PCB, and the relay is a significant fraction of that so
it seems as though keeping proper ground references around would be necessary.
Perhaps the coupling between the bottom side of the relay and your ground
plane (a good-sized capacitor) is enough to make everything kopesetic?
Running a few numbers on the back of an envelope gives me somewhere in the
ballpark of upwards of 10pF (depends on where the ground plane actualyl is,
obviously) which is -j16 ohms at 1GHz -- not entirely ignoranble.
---Joel
http://www.rfrelaystore.com/productdesc.php?pid=RDT-2P1D6 ? If you look at
the mounting drawing link on that page
(http://www.rfrelaystore.com/pdf/mounting/1500901.PDF), the idea is that your
hog out a pocket on your PCB for the relay to sit in and your microstrip
traces contact the relay terminals clearnly. However, shouldn't I be worried
that there isn't really a ground connector between the relay and the PCB's
ground plane that I can see? At 6GHz you're looking at wavelengths on the
order of an inch on a PCB, and the relay is a significant fraction of that so
it seems as though keeping proper ground references around would be necessary.
Perhaps the coupling between the bottom side of the relay and your ground
plane (a good-sized capacitor) is enough to make everything kopesetic?
Running a few numbers on the back of an envelope gives me somewhere in the
ballpark of upwards of 10pF (depends on where the ground plane actualyl is,
obviously) which is -j16 ohms at 1GHz -- not entirely ignoranble.
---Joel