I have the opposite problem. I have a 15VDC supply across a proposed resistor network that has a 10VDC zener setting the bottom voltage. The resistors have to be configured so that the network is tapped at:
These are selected via a rotary switch into a LM339 comparator for a "CUTOFF" action when actual input voltage drops below the selected value, so must be accurate (+/-5%).
It's been so long since I've done this (over 20 years) so forgotten all the formulas to make this. Know the values between points, due to consistant 0.2 voltage increase will be the same, but have no way to determine the top and bottom resistor values at this time. Would like the ends to be between 10-50K and the middle one a common resistor value like 2K.
I'm running KiCAD Suite on Kubuntu Linux, if that helps. It's supposed to have a sim package, but do not think it installed correctly!