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Battery third (temp) terminal as multipurpose analogue input

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Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #30 on: 16 / January / 2014, 10:33:22 »
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I suppose you are right, they are transistors. I think they have three contacts?

If they have three contacts they are transistors.

Using the one that does not work, a photo of the other side of the board would be useful.
Maybe you can even scan both sides of the board ?

Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #31 on: 16 / January / 2014, 10:57:34 »
Definitely need to see the backside  - the one labelled T1 does not appear to have a 3rd solder connection.   Although I suppose they could be transistors wired up as diodes.

Strange.

There is also this :  http://www.flickr.com/photos/timescience/sets/72157623581979614/
« Last Edit: 16 / January / 2014, 11:00:19 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16

Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #32 on: 16 / January / 2014, 12:48:07 »


There is also this :  http://www.flickr.com/photos/timescience/sets/72157623581979614/

Here is one I made earlier (for my S95) from solvent-welded black polystyrene and brass shim.

Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #33 on: 16 / January / 2014, 14:24:04 »
@Karmashinken

If you know someone with a 3D printer ask them to print dummy-battery open-top cases and separate lids.

Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #34 on: 16 / January / 2014, 17:09:44 »
Please have a look at the photo attached. Its the backside. If you need a higher res picture please tell me.

The idea with the 3D printer is a very good one although I would like to try to use the ones I have. They are easily opened and closed.

Now I will try to use waterwingz script tonight to check if I can attach some signal to the contact. I understand the script is meant t o find a channel that is used to read the values? If so,  how do I know I found the right one? Do I need to feed some sort of signal into it,  maybe a steadily changing one from an Arduino?

Thanks a lot!

Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #35 on: 16 / January / 2014, 17:19:42 »
By the way,  I also need the "open battery door"  hack. Where can I find this? Do you know?

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Offline ahull

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Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #36 on: 16 / January / 2014, 17:46:57 »
I think the two components may be zero ohm resistors. (i.e. links) One thought I had was that the board may be dual use. One variant being  as a mounting board for a battery charge control circuit (like the board I extracted from the NB-4L a while back), in other words It could also be the case that you can get a version that contains a lipo cell, allowing you to unplug the power without the camera going off. Its a strange setup however.  The second dual use  would be for this purpose (i.e. as a dummy battery board).

Alternatively the two components  could be reverse polarity and/or over voltage protection of some sort.  Perhaps a diode and a fuse.

I see there are two unused smoothing capacitor spaces on the board too. Most peculiar.


Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #37 on: 16 / January / 2014, 18:24:42 »
As said this is the dummy from China. I can try to find the one from Canon, I have one original branded, but I am quite sure it is all the same in that. It also has that sort of board.

However if it is true what you are writing then one could leave away all that, right? All the "create your DIY-dummy" howtos found on the web do not use any such parts but connect directly to the supply. So it might be the easiest way to build such wooden dummies as described in the link posted by waterwingz.

Actually it is somewhat difficult to make a third contact fit in between the existing two and really stay there. :-)

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Offline ahull

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Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #38 on: 16 / January / 2014, 18:39:55 »
One of those components could be a PTC device.. to prevent over current if you fire in the wrong power adaptor.

"PTCs (positive temperature coefficient) increase resistance as temperature increases. They are designed to prevent unsafe
levels of current while allowing constant safe current levels, and their resistance will “reset” automatically when the current and
temperature returns to a safe level. PTCs are typically used in applications where automatic reset is desired".

It would be interesting to see the Canon version, it may well have different components.
« Last Edit: 16 / January / 2014, 18:44:46 by ahull »

Re: Battery third (temp) terminal as multipurpose analogue input
« Reply #39 on: 16 / January / 2014, 18:44:54 »
By the way,  I also need the "open battery door"  hack. Where can I find this? Do you know?
http://chdk.setepontos.com/index.php?topic=5744.msg57422#msg57422

Ported :   A1200    SD940   G10    Powershot N    G16

 

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