If you have area, use cap, you need calculate the current, ripple to derive your size.
You can get more than a few hundred pF on chip. More than that the cost is high.
Or you can actively control the supply, frequency etc.
Resistive devider, compare with an referece voltage,doesn't need a level shifter
Only compares, Non compensation is OK
With an external stabilzing capacitor, about 1uF, the voltage ripple will be small