A load will be AC motor, but I don't know which one for sure. But I do have schematic of H bridge with elements ( without motor ) if it will be of any help.
Can u explain maybe how to calculate that , or provide some resources ?
edit:
This buck converter that I am designing is going to give 12 V to power the IC on H bridge (ir2112) and few optocuplers , he will not give and voltage to ac motor, so is AC motor still needed to calculate it ?
H-bride without load do not draw current. As for the optocoupler it's depend on the resistors value you use in the circuit.
So maybe show as a schematic, so that we can be more precise in our assumptions.
Sorry Jony It seems I have misguided you. I explained it wrong.
The H bridge will have load ( AC motor ) and it will be powered with 72 V ( or maybe bit higher, but let's assume it's 72V ) , and I am designing buck converter that will convert some of that 72V and give me power to turn on H bridge ( as in IC ir2112 and these mosfets and optocuplers), it will not have any connection to AC motor nor it will need to power it.
This is schematic of 1/2 of bridge, second one is just mirrored.
So your buck converter will only provide a power for Vdd part. If so you don't need to worry about power consumption. Because the static currents are very low as you can read in datasheet.