I have some doubts about the design of this DC/DC converter circuit/PCB circuit:
On the left side there is a 400V to 12V DC/DC converter (Vicorpower DC/DC Mini, 300W). The maximum output capacitance of the converter is calculated with 833.3µF. (Datasheet: "The capacitance value is not the absolute maximum value, but the value for which general application of the converter can be deemed appropriate. Testing will be required to ensure that the module is stable if this value is exceeded. Approximately 10X the value calculated will cause the converter to go into current limit at turn-on.")
On the 12V output side of the converter there are several PCBs. Each of them has some DC/DC converters and some capacitors at different voltage levels. Also, each PCB has an eFuse of the type TI TPS2592AL (programmable SoftStart control). The DC/DC converters on the right hand PCBs are of the type TI TPS6213X (buck converter, programmable Soft Start).
Now I have two questions about this case:
The Vicorpower DC/DC converter has a maximum output capacitance of 833.3µF. Does this only mean I have to add the capacitor values on the 12 V line in front of the eFuse? Or do I also have to add the capacitor values on the 5V/3.3V line of the PCBs for the total output capacitance?
For the circuit calculation of the eFuses I have to figure out the "Load capacitance" of the eFuses. Similar question: Do the capacitors behind all DC/DC converters count? Or just on the 12V line?