I'm staring at the datasheet for the LM237 and I can't figure out how it works since it makes a positive voltage negative, but there is no switching going on.
it doesn't change anything, it just provides a 1.25V reference between the adjust pin (the most positive) and the output pin. The input is a negative voltage.
Yeah, I thought it was a non-switching circuit that somehow inverted the voltage and I couldn't figure out how. Then I realized it made a negative output from a negative input.