PWB? You mean a PCB? Yes, its very doable on a PCB. Needs some careful
design and good artwork on the PCB. Achieving very high spectral purity
and high accuracy over a wide temperature range (temperature mostly
effects your reference input only though) can be difficult but for most
applications (e.g. Bluetooth) very simple designs can be made to work on
FR4 with good results. Though long gone are the days when you had to
design every part of the PLL discretely. There are many PLL ICs now
available that will do pretty much everything for you.

There is a lot of information available on the web on PLLs and
application notes on manufacturer websites. National semiconductors has
Webench online design environment that may be helpful as well
(http://www.national.com/appinfo/wireless). National has some PLL+VCO in
one chip like the LMX2512 (http://www.national.com/pf/LM/LMX2512.html)
but that kinda takes the fun out of designing a PLL yourself. Plus I
don't know if you'll find one for the exact frequency you are looking
for. Maybe you can make that exact frequency by designing a compensated
oscillator as the reference and shift the reference input to the PLL
just a tad bit to get the output frequency you need.

Also if you are completely new to PLL design and RF work, an eval board
for one of these PLL chips may give you a jump start.

Shahid

-----Original Message-----
From: Damien Cahill [mailto:damiencahill@AUSTARNET.COM.AU]=20
Posted At: Wednesday, February 25, 2004 10:21 AM
Subject: [EE]: 1GHz fixed output PLL


Greetings List,

I am currently designing a 1GHz fixed frequency output phase locked
loop.  I am mid way through the design and was just speaking with a
colleague on the feasibility of such an application.  He seemed to think
that this would an extreme undertaking and would be almost impossible to
implement with discrete surface mount components on a PWB.  I'm new to
the field and this has me worried.  Can anyone reassure me or does the
collective brilliance of the PIClist side with the daunting opinion of
my friend.  Thanks in advance.

Regards,
Damien Cahill

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu