Thank you for the question Al!
It is more for the 12v than the 5v, but to allow for the voltage drops in the battery supply side under heavy drive load (see supply drops to 9v/10v during heavy acceleration / motor use). Mainly to avoid brown out conditions for devices that need that stable higher voltage.
My understand as well for why they are stepping up the voltage in the PD for the devices connected there (cRIO, radio, camera). Voltage rail stability. I could be understanding incorrectly as well. (in looking at the schematic, this may be the case of me being off)
Now I see in the PD schematic that there is both a 24v, 12v step up and a 5v buck switching. The corresponding devices i think would step down to 5v and 3.3v.
Now it could be the cRIO only came in 24v, so that could be the reason as well, but would expect the step up would help with supply side stability.
Rethinking (or as the GPS says, recalculating). For the 5v supply I might be able to get away with the buck now that I think about it some more, and may be able to get away with the 12v step up only.
I really appreciate the question as it made me think more about it. Maybe we will just build these like the PD has and do multiple supplies (now to find the best way to SMD
)
I am not a EE, so may be WAY off here.
Thanks!
Randy