I am confused by the voltage divider ratio used in loop gain calculation. Some textbook and application note include this ratio in the open loop gain, but some does not. I was convinced that the the ratio should not be considered in analog control, however, when I design a digital controller for SMPS, coefficient of proportional control is related to the ratio. So, my question is should I include the voltage divider ratio in loop gain? Is it different from analog control to digital control?