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Thread: [EE] 24-bit A/D. Are We in the Twilite Zone Here?
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Andrew Kunz <RemoveMEPICLIST@spam@spam.....MITVMA.MIT.EDU> wrote:

> What we would do is measure an analog signal using the
> time-honored cap/res delay time with a PIC. .... Then we would add a
> random number to this in the range 0-15.
>
> These results were then continuously averaged (Avg = ((sum of
> samples) - Avg) + newsample).
>
> The result was surprisingly accurate.

Andy:

I haven't read any of the previous messages in this thread, so I may
be WAY off-base here... But adding random noise AFTER the A/D
conversion (i.e., adding DIGITAL noise) doesn't give you any more
information than you'd have if you just left the signal alone.  If
you're trying to increase the resolution of your conversion by
dithering, you need to do that BEFORE the conversion, by adding
ANALOG noise.

As I said, I'm not sure what the exact point of the discussion is, so
please ignore this if you were talking about something other than
dithering the signal to achieve higher resolution.

-Andy


=== Andrew Warren - TakeThisOuTfastfwdspamBeGonespamRemoveMEix.netcom.com
=== Fast Forward Engineering - San Diego, California
=== http://www.geocities.com/SiliconValley/2499

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Subject (change) [EE] 24-bit A/D. Are We in the Twilite Zone Here?

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