Would it not be better for phase noise to use a logic gate with a fast
transition than a resistive divider that would be slower due to the load
capacitance?
David
On 10/1/14 7:09 AM, Bob Camp wrote:
Hi
Ok, so it’s not a super duper low phase noise OCXO. It’s also at a reasonably
high frequency.
I’d just drive it into a 5V tolerant input and move on. There are lots of logic
gate chips out there that will run from 3.3 and accept 5V inputs. Use something
reasonably fast and it will do a pretty good job.
Bob
On Sep 30, 2014, at 10:11 PM, Mark A. Haun <[email protected]> wrote:
Hi Bob,
The OCXO is one of those 26-MHz ebay Pletronics from a couple years
back. I would like to not degrade its close-in phase noise (quoted as
-100 dBc @ 10 Hz, -130 dBc @ 100 Hz). Thinking about Said's suggestion
to phase lock a higher-frequency sampling clock to this, with a loop BW
somewhere in the 10-100 Hz range.
I have seen a resistive divider used in a similar application, but
wondered if I could save the couple dozen mA they were spending.
Mark
On Tue, 30 Sep 2014 20:18:56 -0400
Bob Camp <[email protected]> wrote:
Hi
How quiet does it need to be?
Put another way - how good is the OCXO?
What frequency are we talking about?
What is the phase noise “need” after you get to 3.3V (is there a
system spec)?
Bob
On Sep 30, 2014, at 5:46 PM, Mark Haun <[email protected]> wrote:
Is there a "best" way to do this without adding phase noise? For
example, a 5V OCXO into an ADF4002, or a 3.3V or even 1.8V logic
input. Is a resistive divider the way to go?
Mark
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow
the instructions there.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow
the instructions there.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
