Concern:

assuming that leader outputs 5V exactly (since it's what does the step down from 12 to 5). This would affect voltage input to the last PSOM.

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As you can see, minimum voltage required for PSOM is 4.5V. If we're not above 4.5V at each peripheral som's input, it will not work since everything runs off the power regulator (everything is isolated through this).

Research:

Length of car:

"Alright here's the results of the calculation with one wire the entire length of the car. This is assuming 20 gauge wire (if we use 24 there will be less resistance technically, and recommended for 5V is 20-24 AWG) and an upper bound of 1W per board (for a total of 4/5A) which realistically won't happen.I'm a little unsure on whether the wire will be longer than this. It's basically from the leaderboard (around the cockpit) to the back left peripheral (back of the car) and then looping back around to the front right peripheral (middle-ish of the car)." - Ishan Deshpande 

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In order to cause enough of a drop for voltage to be too close to the minimum of the power regulator, we'd need to run wire ~30ft.

CAN Topology investigation:

Note: we run our power lines with the CAN network, so this would affect both.

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A topology like this would also fix our length issues, but it would require development of a power + CAN splitter board that also does some sort of voltage conversion. In terms of CAN topology this means that even if one peripheral node goes down all the other nodes remain active, which is more safety tolerant.

Conclusion:

Option 1 is probably best to avoid having to design a power + CAN splitter board.

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