Taken from reddit;
[–]krillcoin 21 points 13 hours ago
Very aware.
https://i.imgur.com/4qqgoPD.jpgHowever, as this board has only one layer, no vias from the pads, and no decoupling caps near the chip, we can assume the board is completely nonfunctional.
permalinksaveparent
[–]sherryoak 14 points 13 hours ago
yea thats either the worst fake of a pcb design ever or miles beyond anything ive ever made and ive made some serious shit.
permalinksaveparent
[–]Jeff_R 4 points 7 hours ago
The pads for the chips don't even look to be on a copper layer. It looks like they produced them on the silkscreen layer instead of the top copper layer.
If we look at the dark copper layer for what looks like some power or ground distribution traces they are covered with green copper mask....this is normal looking to me.
The chips however have no exposed copper where their pads would go.
This is why the chips couldn't be mounted....they can't solder to silkscreen.
permalinksaveparent
[–]krillcoin 5 points 7 hours ago
Ugh. You're right. They're not even traces, just silkscreen. I've no idea how I didn't see that before.
If we look at the dark copper layer for what looks like some power or ground distribution traces
I don't think so, as they're all going to individual pads on the edge connector. If there's any power or ground, it must be on the other side.
permalinksaveparent
[–]Jeff_R 8 points 4 hours ago
It looks like a total cock up in any case.
I designed my fair share of boards, maybe 35 different ones over the past 5 years in Eagle and Ultiboard. (I used to own a niche manufacturer of parts for race cars.)
It looks like several layers were not sent to the pcb fab house. I can get boards in my hand from China in less than 5 days...I've made my share of mistakes in the past. Usually you send them a zip containing the readme.txt which gives a layer stackup and other info about the production...and the 5+ layer files in gerber format that you need done.
It looks like they have some stuff on the wrong layer (chip pads on top silkscreen layer)...it looks like they missed several layers entirely, many of the minimum 5-7 layers on a double sided board are not there. No vias at all which is basically impossible in any complex design. Everyone minimizes their use of vias but none(?).
Basically I see a tray of unidentifiable chips...they could be anything from Digikey at all in that package size....who says they are even hashing chips? And about $50 worth of faulty boards.