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I have a nice bunch of TI LDC0851 inductive proximity switches and would like to use them for some anti-tamper experimentation, but their connection is 3x3mm WSON-8, which as far as eBay, Digi-Key, Mouser, TI, specialist obsolete product firms and so on have shown to no longer exist outside of somehow finding out some devices they were used in and then buying those devices to harvest the connector. I'm very much game to teardown some stuff to get the proper connectors, but I'm not sure how I would search for and find candidate devices with this specific connector.

I've contacted some firms about fabricating some new sockets from the datasheets and schematics, but cost and time are both absurd.

My idea is since I can have things 3D printed in conductive metals and the contacts on the chips begin at the side then go under, but at a narrowing slant, if I 3D printed eight contacts to fit under the chip a bit and a little up the side for a good contact and then attach surface mount tabs to each, soldering the 3D contacts on each side, is there anything that I'm missing that would cause the chip to not function properly? Interference, likelihood of excess EM radiation that would interfere with the chip reading the EM locations accurately, etc? Basically something beyond my knowledge that would be a reason to keep looking a solution?

Datasheet for LDC0851
UPDATED per Advice from PDF to screenshots and from whatever random file host I was using to Imgur: Datasheet for the WSON-8 in 3x3 https://i.stack.imgur.com/3QqPc.jpg

Edit: Am informed this might be more easily done by other methods. More detail or where I might read more about this or, ideally, both would be appreciated if that's possible.

Edit Edit: Datasheet for socket changed to screenshots instead of PDF and Imgur rather than whatever random file host I had tried before.

Diagram Alley
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  • It’s a complex solution obsoleted by easier technology using other methods that cost less to mass produce. Capacitive anti-tamper, eddy current, coupled PCB coils and optical to name a few. Did you consider other methods? – Tony Stewart EE75 Jul 24 '21 at 08:30
  • I was intending to place these between PCB coils with a the chip between them. – Diagram Alley Jul 24 '21 at 09:10
  • Your WSON-8 link goes to a website that splashes ads and requires a download to inspect the file. Can you post an image instead? You'll get a lot more interest in your question. – Transistor Jul 24 '21 at 09:17
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    Would a "WSON-8 3x3mm breakout board" work? – Andrew Morton Jul 24 '21 at 09:57
  • it's not the adsplash... I'm just put off by someone expending electricity to prevent a user from repairing something. – Abel Jul 24 '21 at 13:00
  • Your intentions still are more effort and expense. – Tony Stewart EE75 Jul 24 '21 at 13:22
  • I'm confuse as to what sort of 'connector' you're expecting to find. These are surface-mount packages and are intended to be soldered directly to a PCB, not placed in a connector or holder of some sort. – brhans Jul 24 '21 at 15:27
  • Why would surface mounted chip contacts taper inward at the bottom and not make contact with the board? In any event they're TI chips and according to TI support they go into WSON-8s at 3x3mm connectors/packaging. – Diagram Alley Jul 25 '21 at 08:27
  • Oh, I didn't post an update properly. I accept that this is basically needlessly complicated. I updated the OP to that effect, but I think it was missed. "Am informed this might be more easily done by other methods. More detail or where I might read more about this or, ideally, both would be appreciated if that's possible. Edit Edit: Datasheet for socket changed to screenshots instead of PDF and Imgur rather than whatever random file host I had tried before." – Diagram Alley Jul 25 '21 at 08:37
  • @AndrewMorton It sounds promising, but the title implies the connecting socket would still be necessary. I checked the quoted search query and didn't find results so I couldn't really check more thoroughly yet. – Diagram Alley Jul 25 '21 at 08:41
  • I don't know if this is helpful, but here is a WSON-8 socket at 6x8mm. https://www.dediprog.com/product/SOK-SPI-WSON68 – Diagram Alley Jul 25 '21 at 08:43
  • @DiagramAlley If you can't find a breakout board that takes the 3x3 mm variety, you could get PCBs made up to fit. You can use free design software like KiCad, and a manufacturer like PCBWay or JLCPCB will get the finished part to you in a reasonable time (watch out for the expensive shipping options that you probably don't need). Once you have something that can plug into a DIP-8 socket, you are in the land of easily-available sockets. – Andrew Morton Jul 25 '21 at 09:15

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