Project's power budget calculation

[barakg]

Hello,

I'm designing my new hobby project. also, it's my first circuit design project
I would like to know how to calculate the power budget for my project. how do you do that?
Do you have excel for this? How did the power budget of OpenRex calculated?

I'm assuming that the power budget shouldn't deviate, for example, the power dissipation of LDO in my project.

Thank you very much

[robertferanec]

What do you mean by "power budged"? Do you mean power consumption?

Usually I check maximum currents for regulators in the reference schematic and I use something similar. Also, we check datasheets. However, there is no way to exactly calculate power consumption for CPU board - they have many different modes (e.g. sleep, idle, max, running graphics, CPU, memory tests, ...) and it really depends on what is inserted inside the board (e.g. one USB 2.0 can drive up to 0.5A, we need to include all USB connectors in calculations, Ethernet can drive different currents when in different modes, ...). When we calculate the maximum power we use all the maximum numbers. After the board is finished, we run some applications and measure the real currents.