The Designer's Guide Community Forum

The Designer's Guide Community Forum
https://designers-guide.org/forum/YaBB.pl
Design >> Mixed-Signal Design >> Slewing vs. linear settling in MDAC
https://designers-guide.org/forum/YaBB.pl?num=1276648756

Message started by carlgrace on Jun 15^th, 2010, 5:39pm

Title: Slewing vs. linear settling in MDAC
Post by carlgrace on Jun 15^th, 2010, 5:39pm

Hi, I've got another question.

I haven't been able to find a good discussion of how to decide how much of the settling time to allow for slewing in a pipelined ADC MDAC. The obvious impact of slewing is that it allows less time for linear settling. Is there more to it that that, though? Assume I have an op amp that can settle much faster than I need for the sampling rate. Then, can I lower the slew rate to save power, since even though there is less time for linear settling it can still handle it?

Will something go wrong if I use have the settling time for slewing? Or 10%? or what? It seems to me if your settling time is fast enough you should be able to slew up a storm.

Carl

Title: Re: Slewing vs. linear settling in MDAC
Post by Mayank on Jun 16^th, 2010, 10:00pm

I am not much sure abt this, BUT
Isn't Slweing + Linear Settling gonna distort your signal ?
& eventaully appear as THD ??
Happens in DACs, not sure abt ADCs.
That's why we make one of the phenomena dominant.