do i have to design the gain ang PM of a cmfb circuit?

[ella1923]

cmfb question

hi all.

do i have to design the gain ang PM of a cmfb circuit? what to do with stable open-loop but unstable closed-loop circuit?

thanks in advance.

 

[fuelight]

cmfb question

the difference betwn open loop and closed loop is loading capacitance / feedback capacitance.

As you know, it changes the pole locations from your calculation

Unless you consider the loading capacitance with each phase , you may face those situation