I have two node voltages that I wish to plot against each other, similar to the XY mode on an oscilloscope. How do I achieve this via LTspice? LTspice only plots quantities against time.
Assuming you are using .TRAN, go to the plot screen, right click on the x-axis label area (time, probably, right now), and change it from time to whatever node voltage or formula you want. That's all there is to it.
Follow the steps indicated by the pictures below:
That's pretty clear, I think.