I guess everyone has seen this, but Linear has a nice appnote «A Standards Lab Grade 20-Bit DAC with 0.1ppm/°C Drift»
http://cds.linear.com/docs/en/application-note/an86f.pdf Ole > 26. nov. 2017 kl. 13:50 skrev Magnus Danielson <[email protected]>: > > Hi > >> On 11/26/2017 02:26 PM, Attila Kinali wrote: >> Though, if you have a decent 16bit DAC and want to get to 18bit, >> that's fairly simple using delta-sigma modulation... if you can live >> with a low pass fillter after the DAC. But the DNL will be the limiting >> factor here (unless you use some special techniques) and the (absolute) INL >> will not get better, for obvious reasons. > > I needed 19 bit rather than 16 bit, so I implemented an interpolation scheme. > A first degree sigma-delta would also be possible, but for low ratios what I > did was more efficient. > > A first degree sigma-delta is fairly simple thought. > > The trick is that you want to push the noise high up so it becomes trivial to > filter, then the filter will not be hard to design and won't be low enough to > cause PLL instability and implementation troubles. > > Cheers, > Magnus > _______________________________________________ > 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.
