FPGA clock accuracy vs tracking accuracy

[NicksonYap]

Hi,

I was studying how the lighthouse deck works and came across this component in the schematic and the repo mentioning:

The pulses are measured in a 48MHz clock

Am I right that the DSC600X is actually 48mhz, and is the more accurate +-25ppm version? standard version is +-50ppm

Would there be any difference if TCXO were used?

So if the clock were to deviate, the tracking would also deviate?

Thanks

[ataffanel]

Yes the lighthouse deck uses a DSC600x MEMs oscillator. It is running at 12MHz, +/-25ppm. A PLL in the fpga generates a 24MHz clock from it and DDR inputs are used to sample the signal at 48MHz.

I do not think using a TCXO would make any noticeable difference in the actual tracking accuracy but this is not something we have investigated thoroughly.