[time-nuts] VCXO help

[Tijd Dingen]

Hello Bert,

That rationale sounds suspiciously familiar. The quest for an ever simpler VCO,
that is. At the expense of some additional phase noise compared to VCXO+PLL, you
could use an ADF4360-9. It is readily available at for example digikey, 
currently 
for $6.26.

For my fpga based counter project I had pretty much the same thing as what
(I think) you are doing. Simplify it wherever possible... So first use a  
PLL with integrated VCO, and see if the phase noise/jitter is not the limiting
factor to your performance. If it turns out to be limiting, you can always do 
the more complicated VCXO + PLL + loop filter later.

Anyway, that ADF4360-9 suggestion is working under the assumption that you
are feeding it something like a 5 or 10 MHz reference signal. And it also 
assumes you don't mind QFN packages. You know, the little buggers with 0.5
mm pitch and no pins.

regards,
Fred



"Bert Kehren" wrote:
> As part of the D/M project the counter uses a 100 MHz VCO with an AD 4001  
> PLL. To simplify further I would like to consider a very simple VCXO, easily 
> available components, no tuning, any ideas out there. For once phase noise 
> is of  no concern.