At 08:54 AM 11/1/02 -0500, Olin wrote:

>1  -  This does not apply to analog inputs.  I have noticed small Vdd
>protection diode current cause significant errors on the remaining analog
>channels.  I'm guessing this is because the internal reference voltage
>gets messed up.

I think it is because of the way currents flow in the protection diodes,
isolation tubs etc.- the current ends up flowing *out* of remaining inputs
in the port. If so, you can expect the error to increase with increasing
input impedance.

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

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