RTC Battery Type

[mmb]

I'm amazed this isn't in the Wiki, but what type of batteries are used for the RTC battery dongle?


Thanks,
MMB

[Ghost]

I'm amazed this isn't in the Wiki, but what type of batteries are used for the RTC battery dongle?


Thanks,
MMB

Taken from the Pine64 shop page, there are two types of RTC battery holder available:

https://shop.pine64.com/collections/powe...-batteries
This one takes two AAA batteries

https://shop.pine64.com/collections/powe...um-battery
This one takes a CR2032 battery

Identify which you have and choose your battery accordingly. Both battery types should be widely available.

[pfeerick]

I'm amazed this isn't in the Wiki, but what type of batteries are used for the RTC battery dongle?


Thanks,
MMB

Taken from the Pine64 shop page, there are two types of RTC battery holder available:

https://shop.pine64.com/collections/powe...-batteries
This one takes an two AAA battery

https://shop.pine64.com/collections/powe...um-battery
This one takes a CR2032 battery

Identify which you have and choose your battery accordingly. Both battery types should be widely available.

The next question is naturally "What is to stop me shoving between 1.5 and 3v down down the RTC battery line on the pine64, instead of getting one of those fancy holders?" (meaning I would like to know at some point what the voltage range is of that port - is it 1.5 to 3v? maybe a bit wider range? Hopefully some more knowledgeable can comment on this?

[Ghost]

My bad, the AAA holder takes two batteries, I've edited my earlier post.

@pfeerick: you could, quite easily and conceivably, fashion your own holder, or indeed use any holder you liked to hold a 3v battery to power the RTC. 

To those not wishing to spend any money yet wanting the benefits of a RTC, I would strongly advise against soldering directly to a battery and directly to the board. Use an appropriate holder and connector.

Direct soldering could damage the battery, the board, and/or yourself.

[pfeerick]

My bad, the AAA holder takes two batteries, I've edited my earlier post.

@pfeerick: you could, quite easily and conceivably, fashion your own holder, or indeed use any holder you liked to hold a 3v battery to power the RTC. 

To those not wishing to spend any money yet wanting the benefits of a RTC, I would strongly advise against soldering directly to a battery and directly to the board. Use an appropriate holder and connector.

Direct soldering could damage the battery, the board, and/or yourself.

Indeed it does... nice spot Ghost! 

After some examination of datasheets (seems to be all the rage for this board... hunting through schematics and datasheets! lol), I have come to realise that the RTC voltage will be either 1.8v or 3.0v. Since it is using a coin cell or 2xAAA, it is most likely set to 3v. So, a CR2032 battery in a holder with suitable 2-pin JST holder it is! As 2xAAA would be plain overkill!  Not that my pine really needs it as it should have network access whenever it needs to sync the time, but never hurts to have a backup just in case...

[psychedup]

My bad, the AAA holder takes two batteries

FYI, The CR2032 holder also takes two batteries. I just got 3 of them. They also have an on/off switch, for when you want to lose track of time, i guess.

[pfeerick]

My bad, the AAA holder takes two batteries

FYI, The CR2032 holder also takes two batteries. I just got 3 of them. They also have an on/off switch, for when you want to lose track of time, i guess.

Hm... handy for that excuse of 'I forgot what time it was?' 

Is that two batteries side by side / in parallel? Thus making the output still 3v?

[dkryder]

adafruit has these items,

https://www.adafruit.com/product/653
https://www.adafruit.com/products/261

they also sell the 5 buck 2 cell [2032] holder for 2 bucks
adafruit has good stuff and they ship quick. for small orders in u.s.a you can get 2 buck first class which in my experience is a day longer than 6.50 2-day priority.
they also have good sales support.

basically, if a company does good work they should get mention.

[NexusDude]

FYI, The CR2032 holder also takes two batteries.

Is that two batteries side by side / in parallel? Thus making the output still 3v?

Yeah, I noticed that, too. Why accept 6V or 3V? It seems far simpler & therefore more likely that the RTC only uses one CR2032. For 3V, that'd be 1xCR2032 or 2xAAA. Does it REALLY use 2 of them, or do 2 just happen to fit if you jam 'em both in there?

I think I've got an extra AAA holder floating around somewhere, and plenty of Alkiline AAAs.

[xalius]

From the datasheet, VCC-RTC is 3V typical, 3.3V max. , 3.6V absolute max.