u/UltraWafflez

Hello, its me again. I made some changes to the buck circuits and left some alone.

• I saw one of the comments on my previous post mention reducing part count, so I decided to switch to the LM5143 Dual Synchronous buck IC in hopes to reduce part count.
  • The original EVM reference I used was a 6 layered board, I somehow managed to squeeze it down to a 4 layered board to reduce cost.
• I also cleaned up and tried to not let let the green traces on the schematic overlap. there's 1 overlap. hopefully that's acceptable
• I still cant quiet figure out what how many MLCCs I actually need, so I just took a guess. The quickstart guide wasnt much help in that regards, but it was very helpful in determining the values of everything else.
  • I asked multiple AI/LLM on how many i actually needed. They started out with an absurd amount (700uF wow), and eventually got it down to about 200 after questioning its logic for a bit (ended up trying to follow the evm amount).
• I used 12A as a reference for the quickstart guide. I probably wont ever reach that much, but the overhead should prevent edge cases.
• Im not quite sure If that one lone aluminum 100uF capacitor is needed. AI kept saying I need it so I kept it there.

Please let me know If I should add anything. any critique is appreciated. I hope the image are clearer this time. last time was kinda blurry.

rough specs:

• 5v @ 12a
• 3.3v @ 12a
• 5vsb @ 5a

I have to preface this by saying this is my 2nd ever pcb design. I initially only made the board to only control power to the GPU connectors (fan revs like mad for 10s to a minute after sleep or shutdown. the time between shutdown and the rev is random. Could be a few seconds or a few minutes). But then I had the brilliant idea of replacing a pico psu since I was bothered by the amount of wires I had to deal with. Little did I know, this is way over my pay grade. I did my best to follow the design shown on the datasheet.

The specs:
5v @ 10a
5vsb @ 5a
3.3v @ 10a

Not sure of the best practices for this type of design, so please let me know.