while using ADC, is it ok to use the unused ADC pins as o/p?

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hi everyone?

quick question...

using some pins of microcontroller ADC port as outputs to drive relays via relay drivers(port PA0-PA5). I am also using two ADC pins (PA6 & PA7) to read values from an LDR. The Adc values are not required to be accurate.

Is there any harm in this design?

Rodney Almeida

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Quote:

Is there any harm in this design?


If your relays change state during a conversion (and that includes bounce/kickback that could be some milliseocnds later), then your conversion results will probably be affected. How much? Only you can tell with your design, how much noise, how well snubbed, etc.

We try to avoid that, during the pin-allocation design phase.

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Pin AVCC runs the port A outs.... so if you start drawing 30 or 40 ma it will probably pull your AVCC down a little, which might pull your aref (if you are using avcc as aref).

Imagecraft compiler user