usually people try not to have unique parts unless needed
pixalynx
waiting for claude's explanatation hahah
pixalynx
```It's deliberate. The board has two different USB-C receptacles because they do different jobs:
J1 (host), J5, J6 (downstream) J2 (power input)
Part Amphenol 12401610E4#2A, 24 contacts HRO TYPE-C-31-M-12, 16 contacts
Carries 10 Gbps SuperSpeed lanes, USB 2.0, CC, VBUS VBUS, CC and D+/D− only
JLC price / stock (today) $1.34 each, about 7k $0.19 each, about 440k
J2 carries power and nothing else. The charger only needs VBUS, ground and the CC lines, which the HUSB238 uses to negotiate up to 20 V. D+/D− also go to the HUSB238. Nothing on that port carries SuperSpeed data, so a 24-contact 10 Gbps receptacle would have eight contacts wired to nothing.
The 16-contact part is cheaper, easier to source and smaller. It's about 7× cheaper and has about 60× the stock. It's narrower (about 8.9 mm body width against 10.5 mm) with fewer fine-pitch pads.
The three data ports are already one part. J1, J5 and J6 use the same connector and the same circuit block. The only difference is the HD3SS3220's role (upstream vs downstream), and J1's contacts are drawn on the other side of its schematic symbol so the drawing reads left to right.
Using the 24-contact part for J2 as well would mean one fewer unique part on the BOM. JLC charges a one-off loading fee for each unique "extended" part (typically $3). For 2–5 boards that roughly cancels out the extra $1.15 per connector, so it's close to break-even. It would also mean re-placing and re-routing the charger input at the back edge of an already routed and verified board. I'd leave it as is.```
Seve
hmm interesting
pixalynx
does that sound about right 😱 ?
Seve
yep
pixalynx
oh perfect 😄
Seve
so you just want to charge with this usb hub
Seve
J2 is used only for power
pixalynx
the front ports are for data
Seve
oh
Seve
i get it
Seve
J2 is for USB-PD power
Seve
yea i understand
pixalynx
yesss
pixalynx
😄
Seve
cool
pixalynx
recommend any changes? if not im gonna send this to fab 😛
Seve
i would ship it haha
pixalynx
wahoooo 😄
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