RTC battery connection


I am looking at the RTC connector on the PCB (in pictures my VIM3 does not show up for another week) and its damn small, I was thinking of getting a standard RTC battery like for a laptop and soldering it in but I am fairly sure this will be near impossible as the header is so tiny.

I noticed two things, there are larger tabs that the JST header solders onto, could I use those?
there is an RTC pin on the GPIO, while I doubt I could use that, I gotta ask :slight_smile:

Not sure who to tag in on this for the team, so I Gouwa if I missed could you redirect to an appropriate teammate please.

Thank you

Hello, The RTC header’s(J1) part number can be seen in the schematic. You would need that connector’s mating connector. Should be easy to find.

The RTC battery is available from the Khadas shop, however, shipping options are limited to pricey ones at the moment. I don’t think it is yet available on the Khadas Amazon shop, but you may want to check it.

Thanx for the reply, I would by far prefer the Khadas RTC battery but I have extensively searched for it and can only find it on the khadas shop at the moment. 2$ battery 30$ USD shipping… NOPE!

I know where the header is, but it is a very small header, de-soldering it leaves two tiny pads and I doubt I can direct solder wires to these pads, and after hitting it with heat several times I bet they pads leave the PCB…

I dont want to turn one of these rather expensive items into a paperweight…
I may have to shelf it for many months before I can make use of it over this issue.

I have been waiting since early feb to get a Vim3 as it is…

I understand your concerns about soldering to the PCB, the traces/pads can be delicate. I would only use hot air soldering and paste in a case like this. However, I think these(2 pin, 1.0mm pin spacing) are the mating female connector for the header. I am not 100% on this. But it is Amazon so sending them back is likely an option. You can find batteries and splice in the connectors.
The Khadas RTC battery spec sheet is seen in this image…

I wish I had something better. Good luck.

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I will say I have seen RTC batteries that look like this, and vertically sit on the small pitch pads…

this one is a bit too big, If I find a suitable size, I will try to follow up…

All the best

Thanx all, I have decided not to risk it and will just shelf the Vim3 until I can get the Khadas RTC battery.