Re: [time-nuts] Precision DACs

chives/philbrick/computing_a > mplifiers.html > > Bob LaJeunesse > > > Sent: Wednesday, July 27, 2016 at 2:15 PM > > From: "Scott Stobbe" <scott.j.sto...@gmail.com> > > To: "Discussion of precise time and frequency measurement" > > <time-nu

Re: [time-nuts] Precision DACs

16 at 2:15 PM > From: "Scott Stobbe" <scott.j.sto...@gmail.com> > To: "Discussion of precise time and frequency measurement" > <time-nuts@febo.com> > Subject: Re: [time-nuts] Precision DACs > > The first reference at hand I checked was the ADI Data

Re: [time-nuts] Precision DACs

The first reference at hand I checked was the ADI Data Converter Handbook, 1986. Pg 60 Discusses track & hold, with a reference to the HDD-1206 as including track/hold on die. On Tue, Jul 26, 2016 at 2:46 PM, Richard (Rick) Karlquist < rich...@karlquist.com> wrote: > > > On 7/25/2016 10:42 PM,

Re: [time-nuts] Precision DACs

In message <2ea1326f-0690-6884-8fc4-29f45c57f...@karlquist.com>, "Richard (Rick ) Karlquist" writes: >The 5071A has a "home brew" DDS that was designed by the late >(and great) Robin Giffard. He used what he called a "blanking" >circuit that disconnected the DAC during the time period

Re: [time-nuts] Precision DACs

On 7/25/2016 10:42 PM, Scott Stobbe wrote: dramatically different due to glitching on code transition. That being said, they are kept separate not to confuse sources of error. FWIW: The 5071A has a "home brew" DDS that was designed by the late (and great) Robin Giffard. He used what he

Re: [time-nuts] Precision DACs

As a clarification, the AD5791 is the minimum implementation of a DAC, it's merely a resistor array with SPI controllable switches. (But an impressive set of resistors, no doubt. Maybe with a dash of secret sauce in digital calibration). The only guaranteed specs for the AD5791 are at DC,

Re: [time-nuts] Precision DACs

On Sun, 24 Jul 2016 23:48:05 -0400 Scott Stobbe wrote: > I doubt the AD5791 does much better than 16 bits operating at 1 Msps, when > you include glitch energy, noise, and distortion. What makes you think so? Yes, if you are using the full 500kHz bandwidth then the

Re: [time-nuts] Precision DACs

On Sun, 24 Jul 2016 19:17:29 -0500 David wrote: > There *has* to be a better way to do this. Maybe we could build a > wooden badger ... What? Has the wooden rabbit failed? As I said, I looked into this some time ago and I couldn't come up with any "easy" way to build a

Re: [time-nuts] Precision DACs (was: NCOCXO anyone?)

The AD5791 specifications under various conditions are all roughly consistent; 20 bits at DC, 16 bits at 10 ksps based on SFDR, and 12 bits at 1 Msps for large code changes. Its intended application is DC where its 1 Msps update rate applies for code steps of 500 or smaller and settling time will

Re: [time-nuts] Precision DACs (was: NCOCXO anyone?)

I doubt the AD5791 does much better than 16 bits operating at 1 Msps, when you include glitch energy, noise, and distortion. On Saturday, 23 July 2016, Attila Kinali wrote: > On Fri, 22 Jul 2016 12:15:25 -0500 > David > wrote: > > > If you

Re: [time-nuts] Precision DACs (was: NCOCXO anyone?)

On Sat, 23 Jul 2016 20:36:28 +0200, you wrote: >On the other hand, a modern DACs like the AD5791 reaches full 20bit at 1Msps >(resp 1us settling time to 0.02% @10V step, or 1us to 1LSB @500 code step). >But using the AD5791 in a design isn't easy either. The dual voltage reference >that is

Re: [time-nuts] Precision DACs (was: NCOCXO anyone?)

The AD5791 evaluation board has an unpopulated area for what appears to be an LTZ1000 reference circuit. Bruce On Sunday, 24 July 2016 7:00 AM, Attila Kinali wrote: On Fri, 22 Jul 2016 12:15:25 -0500 David wrote: > If you expect analog

[time-nuts] Precision DACs (was: NCOCXO anyone?)

On Fri, 22 Jul 2016 12:15:25 -0500 David wrote: > If you expect analog specifications in line with the claimed digital > resolution of ADCs and DACs, you will be disappointed. 20 bits is > about where they top out no matter how many bits are available; the > best you can