Reply by Michael Plante October 24, 20092009-10-24
>I haven't had a chance to read any of the references posted here, so >this may have been described, but one easy way to change the >resolution of an ADC is to use a successive approximation type >converter and only digitize as many bits as you need. The converter >has to be designed to handle the max number of bits you require. You >improve both speed and power by converting fewer bits. Of course this >is not as fast or power efficient as a converter designed for fewer >bit since the comparison operation can go faster and use a lower power >comparator if you design it for less resolution.
Some ADCs will let you set the full scale to be between two external references, rather than GND to AVDD. It all depends on what is really wanted.
Reply by rickman October 23, 20092009-10-23
On Oct 9, 2:33&#2013266080;am, "m26k9" <maduranga.liyan...@gmail.com> wrote:
> Hello, > > I am looking for some facts or specifications about an ADC quantizer. > Firstly I want to know if it possible for quantizers to dynamically change > their resolution? or is it fixed for a quantizer. > > If the quantizer can actually change its resolution, I would be very > grateful if somebody could direct me to a site or a article about this > mechanism. Specifically; > 1) The connection between resolution and sampling rate > 2) Resolution and power consumption. > > Any wisdom or reference is greatly appreciated. > Thank you.
I haven't had a chance to read any of the references posted here, so this may have been described, but one easy way to change the resolution of an ADC is to use a successive approximation type converter and only digitize as many bits as you need. The converter has to be designed to handle the max number of bits you require. You improve both speed and power by converting fewer bits. Of course this is not as fast or power efficient as a converter designed for fewer bit since the comparison operation can go faster and use a lower power comparator if you design it for less resolution. Rick
Reply by Rick Lyons October 22, 20092009-10-22
On Fri, 09 Oct 2009 13:03:06 -0400, Randy Yates <yates@ieee.org>
wrote:

>Eric Jacobsen <eric.jacobsen@ieee.org> writes: > >> On 10/9/2009 1:07 AM, Mikolaj wrote: >>> On 09-10-2009 at 08:33:39 m26k9 <maduranga.liyanage@gmail.com> wrote: >>> >>>> Hello, >>>> >>>> I am looking for some facts or specifications about an ADC quantizer. >>>> Firstly I want to know if it possible for quantizers to dynamically >>>> change >>>> their resolution? or is it fixed for a quantizer. >>> >>> My first thought was oversampling, >>> shortly it is changing resolution within increasing sampling rate >>> (and there is a strict formula on that) >>> >>> Very, very good tutorial is here: >>> http://www.lr.ttu.ee/irm/sideseadmete_mudeldamine/AD_MT_Tutorial.pdf >>> >> >> I don't know who Walt Kester is, but I'm a fan! >> >> That's an excellent reference for all things having to do with ADC/DAC >> technology and issues. > >It *is* a very nice reference. He looks like he was (or is) an Analog >Devices engineer - probably the type that writes their application notes. I >guess these *are* application notes?
Hi Randy, you're right. Some years ago I called Walt Kester to warn him of a rogue Interent site that illegally posted a copy of one of Walt's books. He is a nice guy. m26k9 might want to have a look at: http://www.analog.com/processors/learning/training/design_techniques.html See Ya', [-Rick-]
Reply by m26k9 October 10, 20092009-10-10
Thank you very much for that text... it is indeed really good... many
concepts described nicely...
Reply by Randy Yates October 9, 20092009-10-09
"Alexander Sotnikov" <sotnikov@scideco.ru> writes:

> Walt has been working at ADI for many years. He is the editor of Data > Conversion Handbook and these tutorials are just the excerpts from > there.
Ah! I have a 1986 copy of that book! It is quite excellent.
> You can find the whole book here: > http://www.analog.com/library/analogDialogue/archives/39-06/analog_digital_conversion.zip
Thank you! -- Randy Yates % "Though you ride on the wheels of tomorrow, Digital Signal Labs % you still wander the fields of your mailto://yates@ieee.org % sorrow." http://www.digitalsignallabs.com % '21st Century Man', *Time*, ELO
Reply by Alexander Sotnikov October 9, 20092009-10-09
> >I don't know who Walt Kester is, but I'm a fan! > >That's an excellent reference for all things having to do with ADC/DAC >technology and issues. > >-- >Eric Jacobsen >Minister of Algorithms >Abineau Communications >http://www.abineau.com >
Walt has been working at ADI for many years. He is the editor of Data Conversion Handbook and these tutorials are just the excerpts from there. You can find the whole book here: http://www.analog.com/library/analogDialogue/archives/39-06/analog_digital_conversion.zip --Alexander
Reply by Mirek October 9, 20092009-10-09
On pi&#2013266097;, 09 pa&#2013266108; 2009 19:03:06 in article news:<m3bpkgwldh.fsf@ieee.org>
Randy Yates wrote:
>>> Very, very good tutorial is here: >>> http://www.lr.ttu.ee/irm/sideseadmete_mudeldamine/AD_MT_Tutorial.pdf >>> >> >> I don't know who Walt Kester is, but I'm a fan! >> >> That's an excellent reference for all things having to do with ADC/DAC >> technology and issues. > > It *is* a very nice reference. He looks like he was (or is) an Analog > Devices engineer - probably the type that writes their application notes. I > guess these *are* application notes?
Newer versions here: D/A Converters - Tutorials http://www.analog.com/en/training-and-tutorials/tutorials/design-center/products/digital-to-analog-converters/da-converters/resources/index.html
Reply by Randy Yates October 9, 20092009-10-09
Eric Jacobsen <eric.jacobsen@ieee.org> writes:

> On 10/9/2009 1:07 AM, Mikolaj wrote: >> On 09-10-2009 at 08:33:39 m26k9 <maduranga.liyanage@gmail.com> wrote: >> >>> Hello, >>> >>> I am looking for some facts or specifications about an ADC quantizer. >>> Firstly I want to know if it possible for quantizers to dynamically >>> change >>> their resolution? or is it fixed for a quantizer. >> >> My first thought was oversampling, >> shortly it is changing resolution within increasing sampling rate >> (and there is a strict formula on that) >> >> Very, very good tutorial is here: >> http://www.lr.ttu.ee/irm/sideseadmete_mudeldamine/AD_MT_Tutorial.pdf >> > > I don't know who Walt Kester is, but I'm a fan! > > That's an excellent reference for all things having to do with ADC/DAC > technology and issues.
It *is* a very nice reference. He looks like he was (or is) an Analog Devices engineer - probably the type that writes their application notes. I guess these *are* application notes? -- Randy Yates % "Bird, on the wing, Digital Signal Labs % goes floating by mailto://yates@ieee.org % but there's a teardrop in his eye..." http://www.digitalsignallabs.com % 'One Summer Dream', *Face The Music*, ELO
Reply by Eric Jacobsen October 9, 20092009-10-09
On 10/9/2009 1:07 AM, Mikolaj wrote:
> On 09-10-2009 at 08:33:39 m26k9 <maduranga.liyanage@gmail.com> wrote: > >> Hello, >> >> I am looking for some facts or specifications about an ADC quantizer. >> Firstly I want to know if it possible for quantizers to dynamically >> change >> their resolution? or is it fixed for a quantizer. > > My first thought was oversampling, > shortly it is changing resolution within increasing sampling rate > (and there is a strict formula on that) > > Very, very good tutorial is here: > http://www.lr.ttu.ee/irm/sideseadmete_mudeldamine/AD_MT_Tutorial.pdf >
I don't know who Walt Kester is, but I'm a fan! That's an excellent reference for all things having to do with ADC/DAC technology and issues. -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com
Reply by m26k9 October 9, 20092009-10-09
Dear Mikolaj.
Thank you very much. It is indeed an excellent tutorial. Has lot more
contents than the textbook I was using.

Thank you again.