use a regulated current source to light them, wire them in series and short out the segemnt you want to be dark.

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 you can possibly use a buck-boost converter to make the 30V if you don't already have a suitable voltage.

here's a simple way to build one using a LM2596S module
remove the potentiometer, and both large capacitors, connect one of the salvaged 
capacitor between +in and +out (positive to +in), fit a 1uF ceramic capacitor where the output capacitor was. connect a 100 ohms resistor from the -output to the centre potentiometer terminal.

modified in this way it will create a negative voltage on the -out terminals and act as a 12.5mA current sink at the centre potentiometer terminal (with source at +out) if power is applied between +in and +out

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