Thats the differential op-amp circuit im talking about, the op-amp it self is integrated in a TL1451A PWM chip, so dont have to worry about the supply rails. Bassicly what im expecting is that when i vary V+ through the R25 pot, i want V- to equal that, what is acutally happening, is that V- is equal to V+ over an approximatly 0.1 votlage range, i.e when i have V+ set to 0.8 for example, and lets say i start varying v-, when v- is equal to 0.85V, v+ is the same, however if go bellow 0.75, v+ will stay at 0.75, even when i keep decreasing voltage applied to v-. The same thing applies when i increase v- to be above 0.85, v+ will get stuck at 0.85.
Is this normal?