That was based upon an assumed linear response between 0 and the bias voltage. That’s what the voltage chart in the appendix looked like to me. That of course is before I looked at the magic algorithm.
That’s the reason I asked what your voltage source was. You want to ensure the voltage source has sufficient emf to overcome the bias voltage. A potato won’t cut it. 
May I suggest a quick test with a AA battery to confirm that you see a reasonable value?
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What do you know, I put a battery showing 1.4V on the multimeter and it popped up as 1.4V on the hubitat. I guess these MIMOs are built for quite strong signals and don't actually behave like regular ADCs.
Now to move onto how I can get my sensors to show the right value....I have an RTD sensor and have built a 1 mA current source to run through it so that I can induce a voltage proportional to the temperature. The value for that is not near what (1.7V on multimeter disconnected, but turns into 2V when connected to MIMO) should be showing up. This is now completely MIMO related but, would you have any ideas on how to get something like this running?
Another update, just connected the mimo to a 3.3V source directly to see if it could measure that. the sig1 contacts show 3.3V on a multimeter but the hubitat is showing 2.86V so seems like even their magic equation isn't perfect....
Just for grins, I graphed the algorithm.
Given the graph in the Technical Appendix, the function looks reasonable. And pretty linear up to the bias voltage.
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How did you measure these values? I'm still struggling to get deterministic voltage readings on my MIMO's. The numbers just aren't making sense
Not measurements, just a function graph. The X axis is the 0-4095 input value to CalculateVoltage(), and the Y axis is the return value from the function. I wanted to see how the output of the magic function looked compared with the sensor value graph in the doc.
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