I'm LDO designer ,and all stability simulation were with good PM ,but when i add package parasitcal inductance LDO's PM go crasy -LDO not stable at all
Did anybody meet this kind of problem ?
I'm LDO designer ,and all stability simulation were with good PM ,but when i add package parasitcal inductance LDO's PM go crasy -LDO not stable at all
Did anybody meet this kind of problem ?
Over-compensation means to compensate the loop gain frequency response to a greater extent as derived from the classical BODE plot. Thus, you have "room" for some external unknown parasitic influences which are not covered during simulation.
In your case (if you cannot avoid the mentioned parasitics): Try to modify the (theoretical) design with the aim to have about 80..90 deg phase margin. Then, in reality (including inductive parasitics) you hopefully have enough stability margin.
I know, it sounds more simple as it will be in practice.
What's the inductor value you are using for simulation? if you want accuracy, you may need some resistor in serias with this parasitic inductors. Maybe several mohms.