Hi James,

Interesting experiment.

To help me confirm I understood your test I did the math and all was well
until I got to the second set of readings.

The calculated voltages at the input pin are below.

I am curious how you determined equivalent Input Pin Internal resistance.

..

> Pull-up Resistance to 3.00V: 0.994M-ohm
> Current: 2.28nA
> (Equivalent Input Pin Internal Resistance =3D 1.3G-ohm)
>
 2.964V

>
> Pull-up Resistance to 3.00V: 99.5k-ohm
> Current: 16.6nA
> (Equivalent Input Pin Internal Resistance =3D 181M-ohm)

 3.0046V


> Pull-up Resistance to 3.00V: 9.66k-ohm
> Current: 43.7nA
> (Equivalent Input Pin Internal Resistance =3D 68.6M-ohm)
>
2.99782V


> Pull-up Resistance to 3.00V: 1.00k-ohm
> Current: 51.8nA
> (Equivalent Input Pin Internal Resistance =3D 57.9M-ohm)
>
2.99922V


>
>
--=20
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