I am looking for an LED driver circuit that would illuminate when a voltage is at zero, and which would gradually shut off as a voltage rises to 3.3v, with a (somewhat) direct relationship between brightness and voltage level. I have already designed this circuit using an inverting op amp to invert and offset the control voltage signal with a negative reference, and then a second op amp to drive the LED using the feedback path. I am hoping that someone might know of a simpler design, that would be lower cost and fewer parts. As it stands, this will cost me about $0.30 and uses 5 parts (not counting the LED itself) [![Inverting LED Driver Circuit1][1]][1] And here is the signal analysis, where the Green line is the 0-3v3 control signal, and the Blue line is the current used by the LED itself. [![enter image description here][2]][2] [1]: https://i.sstatic.net/eeqFH.png [2]: https://i.sstatic.net/Id0yz.png