Re: [avr-gcc-list] AVR ADC

[Clemens Koller]

Hi, Benjamin!

NEMEC, BENJAMIN schrieb:
> " Just use common sense. "
> I like to think I have some level of common sense, but I try to know my
> limits.

Well, from my point of view there are solutions which "just work" and
there are the more "engineered" solutions.

A 100nF X7R ceramic should be "okay".
1uF should also be okay, but IMHO not necessary.
For a propably "better than okay" solution I would recommend a
100pF C0G or even a more priced 1nF C0G capacitor in parallel to
the above, close to the pins, to be very sure to get rid of any high
frequency components.

As the datasheet says: "..., and the reference voltage can
be made more immune to noise by connecting a capacitor..." and
"...Vref is a high impedant source..."
I would take care that the PCB traces stay as short as possible
not to pick up any external noise. If you have the choice,
put a GND-Plane around the analog part, decoupled from any
digital/switching pins/loads.

With proper signal conditioning, it should be quite easy
to get to the specified performance of this 10 bit ADC.

Good luck,

--
Clemens Koller
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