Sure, transistor tolerances just like all manufacturing tolerances and standardization are my personal definition, uhuh.
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This must be why there's a thread on denying the utility of dividing by 1023. Because of me. Everyone else knows better. This just gets funnier.
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Just because your calculator spits out a string of digits, reality only matches so many in a row.
The ADC step is almost 5mV wide with 5Vref, you can stop at 2 decimal places.