Yeah. I was fearing it was multi layer. Was hoping I could just find the two positive/negative feeds. But of cause if they are to multiple places on the other side of the board,
No replacement battery/boards available AFAIK.
As it is a rather random tablet, with multiple revisions, getting a "dead" unit for scavenging parts is also going to be risky I guess, in case it's totally different.
PS, I'm wondering if the two cells are just connected to the same master + and - terminals? Is that too much of a long shot/*really bad idea*?
Thankyou!
Let me know if they need to be closer/higher res again, and I will see if I can figure out how to get closer focus on the camera.
PS, obviously putting a battery + to a + is a bad idea. I guess I meant asking if they charged in parallel, in which case a repair would be easier, as just connecting the positive to negative on one side, and finding where the other positive or negative needs to feed in (which ever master line I've broken).
Are those probe test points on the rear? Could I use those?
Also picture the broken ends so we can see if it is multi layer board.
If those bottom traces are only traces repair is easy but those cans in left side are hiding something (they look like cans)
OK. Rebuilding the board is probably past my expertise. Well, it does only have 7 components. So I guess not impossible, but as you said, safety is important.
I know I might sound stupid asking questions when I really don't have the knowledge to know where to begin, but... what prevents me just bridging the surface traces? There are 3 feeds across the rear of the board for example. Top, middle and bottom. Top appears to be connected to nothing. Middle and bottom seems to be the positive and negative lines?
As an aside question. Where do they keep temperature monitoring on these things? I only see the positive and negative terminals on the actual batteries...
The third option is finding an existing board that does two cell charging? But I'd not know which parts shop/hobby shop to search for that kind of thing. Something like: https://learn.adafruit.com/multi-cell-lipo-charging/simple-balance-charger (Though that won't fit in the tab without modification ).
It's probably two thick traces for power, and the thin one in the middle for a thermistor.
I wouldn't bother trying to glue the board back together, but just jump across the traces with wires --- that way they will stay as two flexible pieces, should you ever decide to open the unit again and forget that this happened.
QuoteOK. Rebuilding the board is probably past my expertise. Well, it does only have 7 components. So I guess not impossible, but as you said, safety is important.
Most likely unfeasible as you would not have the right materials/tools.
QuoteThe third option is finding an existing board that does two cell charging? But I'd not know which parts shop/hobby shop to search for that kind of thing. Something like: https://learn.adafruit.com/multi-cell-lipo-charging/simple-balance-charger (Though that won't fit in the tab without modification ).
You cannot just use random charger it must be suited for your application.
Actually quite a good learning project for someone interested in electronics because the board is so simple.
Though I agree with your concern on the safety aspect, but I just want to drop a note that you made it too unreal.
Firstly, as if you have known all the chips on board and have the library to the package, device and the chip schematic, don't even talk about routing the board.
Obviously you also assume OP has the knowledge of the pcb manufacturer requirements and submission standard and protocol, don't even begin to talk about $5.
Assuming he took months later to manipulate the software, his first submission and the board will be prone to errors.
Furthermore smd skills and tools costs to weigh in.
I reckon, for those who already have the skills and knowledge, they would not be opting for the new pcb board, because they would already know how to wisely and sturdily bridge the board, right?
And because I don't know OP's level of knowledge, particularly I cannot afford and be blame for his injury, so I won't even think of suggesting how to proceed. I don't know really.
Firstly, as if you have known all the chips on board and have the library to the package, device and the chip schematic, don't even talk about routing the board.
Obviously you also assume OP has the knowledge of the pcb manufacturer requirements and submission standard and protocol, don't even begin to talk about $5.
I reckon, for those who already have the skills and knowledge, they would not be opting for the new pcb board, because they would already know how to wisely and sturdily bridge the board, right?
And because I don't know OP's level of knowledge, particularly I cannot afford and be blame for his injury, so I won't even think of suggesting how to proceed. I don't know really.
What the heck are you on about?
if it came from a tablet, I would be careful because there could be some special features not found in the generic protection boards - e.g. a temperature sensor or something else. If you want to replace it then a careful reverse engineering would be in order first to make sure the function is completely understood.
This is so simple board that it could be designed with a pencil on paper or in Fritzing (not that I recommend it). It also limits how many rookie mistakes can be made on it, especially since we are talking about making an exact duplicate of an existing design, not designing a board from scratch.
It's probably two thick traces for power, and the thin one in the middle for a thermistor.
I wouldn't bother trying to glue the board back together, but just jump across the traces with wires --- that way they will stay as two flexible pieces, should you ever decide to open the unit again and forget that this happened.
Yeah why do proper repair when you can do half ass job I forgot my motto.
It's probably two thick traces for power, and the thin one in the middle for a thermistor.
I wouldn't bother trying to glue the board back together, but just jump across the traces with wires --- that way they will stay as two flexible pieces, should you ever decide to open the unit again and forget that this happened.
Yeah why do proper repair when you can do half ass job I forgot my motto.I'd consider an improvement. The board does not need to be rigid, and the only reason they used one long one is because of manufacturing cost.
I will look at bridging the traces. As said, I cannot see any temp connections (only positive and negative from the cells). It may only be load balancing. It also only seems to have positive and negative to feed into the main board (though 3 wires for each red and black, total of 6, they are soldiers into one positive and one negative terminal only).
Space is not a real concern in this model, with possible enough room for an entire 3rd cell, lol. I would probably only use it sparingly or while under supervision if I did a successful repair, as I'd not expect it to last forever. But it is an opportunity to make good something that would become scrap (as I'm assuming the firmware will not boot without a battery, which is stupid IMO, but I understand as it cannot know if batt removed safely, or batt failed dangerously). Else I'd use it without the cells as a nice Windows Powered Picture Frame.
This is more to see if it can be done, what the results are and then move on from there.