[sdiy] Ratio switching!

[Louis van Dompselaar]

> For example a desired 2416.33mV would require (E24) 16.000k ohm and 
> a 5.100k ohm which gives at best a voltage of 2417.06mV error of 0.01661%
>
> Not to bad!
Although it will only be as good as the best components in there.  If 
you want
around 0.01% accuracy, the resistors will have be (and remain at any
temperature) 0.01% accurate as well.  There's the catch.

Louis