Hi time nuts,
I'm looking for a 5x frequency multiplication scheme to let me use a
16-MHz square-wave OCXO for an ADC encode clock at 80 MHz.
Constraints in order of importance:
1. Don't degrade the nice phase noise of the OCXO (-90 @ 1, -120 @10,
-140 @ 100, -160 @ 1k) any more than necessary;
mag...@rubidium.se said:
> I was amazed that it was this simple to move energy to where it makes less
> damage. Turns out that FPGA logic wise, it's at the same cost as PWM.
You can do the same thing in software. Many small CPUs have IO gear that lets
you send raw bits. Just setup a buffer
Patrick,
I try to share what I have learned as generously as others before me
have done. Somewhere along the line I transitioned from noob to actually
know something and now, well, I can't claim complete lack of knowledge
anymore. But, I enjoy the many questions, as it forces me to think,
think
Magnus,
Well you kindly explain what you mean by your comment "I've seen
both instrument makers and oscillator makes handwaving to protect the values
which so far is understood to be non-physical." , especially the
non-physical part.
While I can keep up with a lot of the discussions here, I will
I think one should recall that for very deep phase-noise numbers for
far-out noise, we cannot remove the suspicion of cross-correlation
cancellation problems have overstated the phase-noise levels. I've seen
both instrument makers and oscillator makes handwaving to protect the
values which so far
Hi,
God points! I know I have both the integrator as well as bandwidth
limitation of the EFC to help me further. For the application the main
focus was to increase the resolution, and I was taking care of secondary
consideration of phase noise contribution.
This reminds me that I've not taken
Hi
One thing to remember in this:
Since the EFC is FM and you care about PM (phase noise) the
FM to PM math gives you a “free” LPF. Get the spurs high enough
and they get pretty far down. You also want to get out in the “flat”
phase noise region. Otherwise you are chasing an ever decreasing
Hi,
Sure. I want people to mentally retire PWM, it's only benefit is that it
is easy to understand, but it to some degree have the worst property you
can think of.
I did a very simple trick. First of all we have a "low" or "high" value
to output to the DAC. The "low" value is the higher bits of
