CR2032 Battery holder - sanity check
#11
Its a 3V battery, so 2.85V with two in parallel makes perfect sense. I need to get a couple batteries and test, as I, like xalius, looked at the holder wiring and were skeptical..I opened mine up after seeing his post and agreed with what he was wondering about...doesn't there is nothing else in the holder besides switch contacts, wire, and the switch itself. I see a small piece of shrink tube on one contact at the switch...so doubting its anything at all exotic.

Installed as the holder seems to indicate, the + and - terms of the two batteries are connected..so at the moment, not seeing how they undo that series connection. Will definitely look at it closer later this evening or tomorrow morning.
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#12
One thing i notice is that the voltage start at something below 2.6 and increase with time after a few seconds. May be a capacitor?
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#13
Nope, no need for a capacitor. This is a simple battery holder, nothing more exotic.

Common lead is attached to one of the +/- junctions (if you follow the imprint on the case), positive lead , thru the switch, to the other +/- junction.

Going to pick up a couple batteries tomorrow, but just not seeing how you get 3V with them installed as per the case imprints. Install them the same way, and you have two 3V cells in parallel, as I would think was intended.
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#14
Picked up two 2032s, and confirmed what I expected to see, and it is exactly what Xalius saw.

Installed as per the imprint in the case, you have the two batteries in parallel bucking each other. Couple tenths of a volts at the terminals, as one would expect to see.

Flip one, so you have battery polarity the same way, you now have the two 3V batteries in parallel, and of course have 3V at the output.

Definitely appears, as was originally stated, the battery case is mis-marked.
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#15
Mehh, You won't believe but this explains why my (wrong) wiring works: https://plus.google.com/photos/photo/113...9qH8vnl6AE

** This video is made for education purpose **
DON'T trust every single battery coin without checking.
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#16
(07-25-2016, 05:55 AM)@lex Wrote: Mehh, You won't believe but this explains why my (wrong) wiring works: https://plus.google.com/photos/photo/113...9qH8vnl6AE

** This video is made for education purpose **
DON'T trust every single battery coin without checking.

Makes sense..dead or defective battery. With the huge delta between the two cells, as they were connected, you don't see the minimal difference as you would from two fresh batteries connected that way.

The also explains some of the behavior you saw that you mentioned a few posts (#12) previously.

I pinged KH Gog and TL Lim re the issue; not that its anywhere as major as some of the other issues being worked, but if nothing else, a note on the wiki, or even something inserted with the batter holder, would help those who may not look at it as closely when installing batteries.
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#17
can someone explain why 2 cells are needed for the pine64? is it just for extended lifespan of the rtc? i have been using 1 2032 for a month and the time has been good every boot. my experience is these single cells last for years during normal duty. this board is the first i have owned that suppopsedly needs 2 cells.
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#18
I assume its for the higher-than-typical RTC current draw spec of 1 mA, compared to typical.

There's no peak current draw issue, so would expect its a battery lifetime issue.
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#19
sounds right , Don. although I was not aware of the 1mA
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#20
(07-25-2016, 10:02 AM)dkryder Wrote: sounds right , Don. although I was not aware of the 1mA

For the record, I'm quoting xalius, and trusting his source.. Smile Smile
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