On Wednesday, June 11, 2008 6:07 AM [GMT-3=CET],
Xiaofan Chen  wrote:

> On 6/11/08, Alan B. Pearce <A.B.Pearce@rl.ac.uk> wrote:
>>> Use the AD reference at 4V or so. Where do you get inexpensive
>>> 4V or so reference?
>>> TL431 or LM431
>>
>> Anyone looking for low noise accurate references may like to look at the
>> new Analog Devices range. Look at the ADR44x range, each voltage output
>> comes in 2 grades of tolerance, and includes 2.048 and 4.096V references.
>
> That is a totally different grade of component than the TL431. I am
> using ADR03 and tried ADR421 as well because of their good temperature
> drift performance (3ppm worst case). They have much better
> speciifcation than the TL431 and are much more expensive as well.
>
> But TL431 is more than a reference. You can refer to the following
> written by the famous R. B. Ridley (ok, he is famous only in the
> field of power electronics).
>
http://switchingpowermagazine.com/downloads/15%20Designing%20with%20the%20TL
431.pdf
>
> Xiaofan

I always believe that it was a mere *adjustable* zenner, excellent article.
Dennis.


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