I have a SIM7600G-H modem and assuming no possible controls, the sim card is exposed to condensation entering the enclosure and is corroding (not subject to water damage).
I was wondering if there is a gel that I can use to coat the sim card to prevent it from corroding over long periods of time, while not impeding on the contact between the sim card and SIM7600G-H sim card slot reader to ensure it can still communicate with the board.
I did research and found TefGel Corrosion Eliminating Gel which is used for electronics, however I am unsure if this will prevent the electrical contacts from working between the board and sim card.
Also, if you have any other gel recommendations that would be much appreciated.
First idea that comes to mind is using conformal coating to coat the board. We have a range of sizes available here.
It would just require either masking the contacts when applying or scraping it off after the coating is completed.
Another option that I’ve seen used for CPU sockets on motherboards for Sub-Zero computer cooling systems is Vaseline or dielectric grease. It would be a lot messier but would do the job ensuring condensation cant form between the SIM and the PCB
Hi Nick.
How often do you need to remove the Sim card. If hardly ever Aaron’s idea of conformal coating has merit. The idea would be to coat while the Sim card is in place. the coating can be removed to remove the Sim but this can be messy unless you are careful. I have replaced components on a conformally coated board and while a nuisance it can be done and the board is recoated at that spot after the operation. When coating you would need to stop the coating substance getting down into the card holder or it would be near impossible to remove the card.
If you just coat the Sim anything you use will be an insulator or if conductive will be a short between contacts. If you clean the contact area you will still get corrosion at that point as you will have removed the protection.
Another way would be to seal the whole thing in an enclosure.
It all boils down to if you have a moisture problem you are better off fixing it at the source. get rid of the moisture or seal everything. It is a bit extreme but pressurisation would help.
Cheers Bob
