I am designing an electric veichle controller for a University project. The motor driver receives an analog signal (0-12V) to adjust the speed. I use a digipot followed by a buffer to convert the digital signal of the controller to ana analog one. Now I need some way to enable an disable each motor independently. I thought I can achieve this by cutting the supply power off the Op-Amp, but I have no idea how. I think there is Op-Amp with a disable pin, but I cannot what the state if the output is when the Op-Amp is disabled and I tried to simulate it using proteus software but it does not seem to work at all, further more I couldn't find this kind of Op-Amp locally to actually try it out. I am interested to know what you guys think. I will attach the schematic below.
Edit: I also thought about adding a comparator and supplying power to the buffer from the output of the comparator. But think this could be unnecessarily complicated.