I set up an inverting Op-Amp with the following schematic, inputting a 32.8 kHz signal. Two identical resistors on each side of the inverting input. Bias voltage is 7.5 V, Supply voltage is 15 V and 0 V respectively.
I expected an output like this, where the input is near-identical, but 180 degrees out of phase to the output. (This is done with the LTSpice's own near-perfect Op-Amp)
Instead, I got this. I don't know how to describe it with words. Green is the output.
I'm aware that the inadequacies of the LT1490 Op-Amp is a cause in it, but I'm not sure why as the datasheet gives a gain bandwidth product of 200 kHz, which suggests that this Op-Amp should be able to handle operations much less high-speed as 32.8 kHz.
I'd like to solve this problem without getting another type of Op-Amp if possible as my budget is low though I'm open to using other high current, rail to rail op-amps (preferably low-cost with recommendations) if needed.