jlcpcb is amazing but do they really E-Test? - Page 1
Forum section: electronics / general

author: russian2
author_rank: Contributor
timestamp: April 13, 2022, 05:21:17 pm
content: Over three years I've placed about 80 orders with jlcpcb, majority of those with assembly not just PCB. Overall an amazing experience.Yesterday was what seems like second even fabrication mistake, previous fabrication issue was over a year ago. In the order which we've received yesterday it looks like a few vias are shorting planes which should not be shorted.That makes me question the 100% e-test claim athttps://support.jlcpcb.com/article/50-e-testQuestion: has anyone experienced any fabrication defects with JLCPCB personally? Would your experience with JLCPCB defects make you question the 100% flying probe test claim?

author: wraper
author_rank: Unknown
timestamp: April 13, 2022, 05:29:46 pm
content: Had such an issue on a single board. One of QFN outer pads was shorted to a GND pad in the middle. There was another time when a few nearby traces were interrupted, and their interrupted ends were moved in wrong places. Not 100% sure if the latter was JLCPCB though.

author: georpo
author_rank: Contributor
timestamp: April 13, 2022, 05:59:27 pm
content: If you check on their online calculator you will see that above a specific quantity the default option for testing is "random test".From the link you posted it says that the PCBs undergo 100% AOI test and that they can be tested with flying probe as well, but I guess you will have to choose it.

author: russian2
author_rank: Contributor
timestamp: April 13, 2022, 06:02:30 pm
content: the order in question has "Flying Probe Test: Fully Test" option in product detail

author: russian2
author_rank: Contributor
timestamp: April 13, 2022, 06:05:06 pm
content: Quote from: georpo on April 13, 2022, 05:59:27 pmhuh? i read "boards with 2 layers and above will always be 100% tested with a flying probe."

author: georpo
author_rank: Contributor
timestamp: April 13, 2022, 06:11:16 pm
content: To be honest you are right, but I understood something different when reading it.I understood that the PCBs will be 100% tested when they will undergo a flying probe test, not that they will necessary undergo if you do not choose it.From 50 pcs and above you need to choose the option "fully tested"How many pieces was your order to start with?

author: georpo
author_rank: Contributor
timestamp: April 13, 2022, 06:15:33 pm
content: Quote from: russian2 on April 13, 2022, 06:02:30 pmSo maybe they do not make a fully test even if you ask for it.Also to ask your question if I experienced such issue, yes I have. Where I work we assemble boards that the customer send to us.I have seen the exact issue happening before.

author: thm_w
author_rank: Super Contributor
timestamp: April 13, 2022, 10:24:08 pm
content: Do you have a microscope? Look for any indentation on the pads. I see none, which would indicate they don't check many of the boards, or use optical only. They probably know the process is good enough.Previous discussion:https://www.eevblog.com/forum/manufacture/jlcpcb-bbt-(not)/

author: 48X24X48X
author_rank: Frequent Contributor
timestamp: April 14, 2022, 05:24:36 am
content: For small order, the test is included. But if you order big quantity, it is an option that you need to pay extra for. On top of that, if you want it be perfect against any scratches or whatever, you need to pay for that too. You can easily check if they are tested by looking for the small tiny pin marks on your pads.

author: russian2
author_rank: Contributor
timestamp: April 19, 2022, 08:47:28 pm
content: Status update: it was our mistake, we've messed up and JLCPCB has fabricated exactly as we've ordered. Not a JLCPCB fabrication issue.Also we just had our own turn around record time: 9 days from PCB+ASSEMBLY order to delivery on the East Coast. WOW! JLCPCB+DHL is an unbelievable combination.