According the block diagram the error amplifier is compensated internally (PI-type regulator based on the shown RC-element).
Almost all design examples in the datasheet shows 100uF capacitance on the output. Sometimes (at lower output voltages 200uF are shown). Also to load transient plot is based on 100uF and shows quite high transients. Its written that " Transient performance can be improved with a higher value output capacitor and the addition of a feedforward capacitor placed
between VOUT and FB. "
The indented application is to supply an processor at 1V. Load transients must be significantly lower than shown in the datasheet plot. We are also concerned about the control loop stability.
I would like to ask which control loop stability (phase and gain margin) can be achieved; especially when load capacitors or a feed-forward capacitor is added?
It's obvious that the control loop stability depends on the output capacitors (including ESR of the load capacitors,..) as well as on the settings of the EA-compensation. A feed-forward capacitor will also increase the gain and maybe decrease the loop stability.
Do you have a average model of the implemented control loop of the LT8613? This would help to simulate the loop performance with the real load capacitor (model).
