imho, sound like you need a new battery. . do you have access to a voltage meter and a soldering iron. . i think a thorough test is needed first ( in circuit and out of circuit ) and would seal the deal ( necessity ). . google is your friend. . look for eatatjoes posts !
Battery not charging at all
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had the same problem when i flashed my dropad a8x with a new firmware because i thought the battery not charging issue was a firmware bug. now i cant use it even pluged in on a wall chardger.
thanks for the advice but i cannot access the site!? i would try this first but any other place where i can find the procedure???
Here is the link:
http://www.99pad.com/thread-25029-1-2.html
Here is the picture with instruction in Chinese:
Attachments
The tablet is a gift to my father. The charging problem appears 4 months after getting it from Merimobiles.
Thanks to purplesun's post #33, I manage to fix the problem by replacing the MOSFET mentioned in post #72 of The tablet no longer be charged, what to do?
The MOSFET may be dissipating too much power than it can handle (AntonSV Date • 22.06.2011, 19:02). I replaced the SOT-23 Si2305ADS with a SO-8 FDS4435A I found in my workshop. It has been 20 days since I replaced the MOSFET and it takes less than 3 hours for the charging LED to change from red to green(19% to 100% charge)
If the controller IC EUP8057Q fails, it may be a bit difficult as the pinouts for EUP8057Q(MSOP-8 ) and BQ2057WTS (TSSOP) are different. (Post #68 of The controller battery )
Kernel version
2.6.35.7
MID Serials #123 Fri Sep 30 05:54:06 EDT 2011
Build number
MID Serials 2.3 GINGERBREAD 20110921-113041
Thanks to purplesun's post #33, I manage to fix the problem by replacing the MOSFET mentioned in post #72 of The tablet no longer be charged, what to do?
The MOSFET may be dissipating too much power than it can handle (AntonSV Date • 22.06.2011, 19:02). I replaced the SOT-23 Si2305ADS with a SO-8 FDS4435A I found in my workshop. It has been 20 days since I replaced the MOSFET and it takes less than 3 hours for the charging LED to change from red to green(19% to 100% charge)
If the controller IC EUP8057Q fails, it may be a bit difficult as the pinouts for EUP8057Q(MSOP-8 ) and BQ2057WTS (TSSOP) are different. (Post #68 of The controller battery )
Kernel version
2.6.35.7
MID Serials #123 Fri Sep 30 05:54:06 EDT 2011
Build number
MID Serials 2.3 GINGERBREAD 20110921-113041
I used a metal paper clip to finish the job.
But before you do, shield one end of the paper clip with plastic tape to prevent electric shock when you hold the clip by hand.
Good luck!
Oh I see I connect each end of the paper clip to the two connections for less than a second....
That reminds me when I did this on an old cellphone camera flash accessory (I shocked myself XD)
Thanks Syan
Sorry for the 3rd post in a row but I think I killed my tablet. I desoldered the baterry to solder the jst-hx connector and when I reconnected it it wouldn't turn on. The led is full green and blinks red when pressing the power
button.
I tried jumping the tablet by using a 9V current just like the PDF says but nothing. I also tried formatting the SD inside the tablet but it wouldn't read in my computer (and it got really hot too).
So I guess i'm done with the Dropad...
button.
I tried jumping the tablet by using a 9V current just like the PDF says but nothing. I also tried formatting the SD inside the tablet but it wouldn't read in my computer (and it got really hot too).
So I guess i'm done with the Dropad...
Sounds like you may of damaged it somehow, example wire slipping over the board and hit a contact, or your solder tip shorted out on another contact during de-soldering of the power wire, or the wires are crossed, etc..
You may want to detach the battery all together and then plug it in with AC adaptor and see if you can get a power on. I haven't read your entire situation so I don't know if you were having powering on issues before all of this or not while plugged in. I just got my C8 today, I hope mine don't die to soon from this battery failure it is prone to. However once it does I think I will just get the dx charger and swap cables and then solder in the bypass to the batteries like eatatjoes did.
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Hi, I'm new in this forum.
I'm from Panama so sorry for my english.
This my problem, in september I recived me tablet Dropad A8 from DX and all its cool, only for one thing. The screen had a white spot and the back cover had an elevation.
The tablet had problems with the charge, at the beginning I used it for 2-3 hours, and then 1-2 hours in octuber had dead. Only could be used with the charger connected.
And my question is the next. I will to order this pack battery: http://www.sunsky-online.com/view/211100/Battery+for+S-WMC-0197.htm really the shipping cost don't matter.
How I replace this? I can cut the RED-BLACK cable and then unite with the cables of the new battery?
This are image from my open Dropad A8, and it can see the elevation of the battery, it's broken.
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I'm from Panama so sorry for my english.
This my problem, in september I recived me tablet Dropad A8 from DX and all its cool, only for one thing. The screen had a white spot and the back cover had an elevation.
The tablet had problems with the charge, at the beginning I used it for 2-3 hours, and then 1-2 hours in octuber had dead. Only could be used with the charger connected.
And my question is the next. I will to order this pack battery: http://www.sunsky-online.com/view/211100/Battery+for+S-WMC-0197.htm really the shipping cost don't matter.
How I replace this? I can cut the RED-BLACK cable and then unite with the cables of the new battery?
This are image from my open Dropad A8, and it can see the elevation of the battery, it's broken.
If you know how to solder what I would is cut the wires one at a time to remove the battery from the tablet. Then un-solder the remaining wire from the board. Then when you get the new pack, cut the plug off, to where the wires have enough length to reach the area to be soldered back onto the board. Then just solder those wires back in making sure you put the positive and negative where they go. Also when soldering make sure you DO NOT short the wires, make sure your solder tip doesn't touch the other wire after it is already soldered in.
If you don't feel safe doing this, or don't know how to solder then you can splice the wires, cut the wire from the old battery and then cut the plug off the new battery and then splice the correct wire to each other. However even then I would recommend you solder the wires together instead of just tape or a wire connector. If I did it this way I would solder and then heat shrink wrap the wire.
If you don't feel safe doing this, or don't know how to solder then you can splice the wires, cut the wire from the old battery and then cut the plug off the new battery and then splice the correct wire to each other. However even then I would recommend you solder the wires together instead of just tape or a wire connector. If I did it this way I would solder and then heat shrink wrap the wire.
Hi all
Well i did a bad bad thing ............ bought a cigar lighter power adapter and plugged my tablet in with the wrong polarity .......dumb
End result my tablets red and green leds light up at the same time and it isnt charging...............
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so after a lot reading ive ordered the dx li ion charger and decided to add a new charging port.
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i ust xt connectors from hobbyking (robust and impossible to inverse polarity)
What i would like to know is if i correctly did the job.
i soldered the new port to the + and grnd on the main board where the battery is connected and that is all. Is this all i need to do or do i need to do anything else .
What im asking is , is that the way to do the pigtail ? and will my job work with the dx 8.4 charger.
Many thanks for any enlightenment
Well i did a bad bad thing ............ bought a cigar lighter power adapter and plugged my tablet in with the wrong polarity .......dumb
End result my tablets red and green leds light up at the same time and it isnt charging...............
so after a lot reading ive ordered the dx li ion charger and decided to add a new charging port.
i ust xt connectors from hobbyking (robust and impossible to inverse polarity)
What i would like to know is if i correctly did the job.
i soldered the new port to the + and grnd on the main board where the battery is connected and that is all. Is this all i need to do or do i need to do anything else .
What im asking is , is that the way to do the pigtail ? and will my job work with the dx 8.4 charger.
Many thanks for any enlightenment
Joined
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2 Posts
Hi, can you send me the PDF please?
thank you
[/quote]
thank you
[/quote]
Hi Bao,Hi all
Well i did a bad bad thing ............ bought a cigar lighter power adapter and plugged my tablet in with the wrong polarity .......dumb
End result my tablets red and green leds light up at the same time and it isnt charging...............![]()
so after a lot reading ive ordered the dx li ion charger and decided to add a new charging port.
![]()
i ust xt connectors from hobbyking (robust and impossible to inverse polarity)
What i would like to know is if i correctly did the job.
i soldered the new port to the + and grnd on the main board where the battery is connected and that is all. Is this all i need to do or do i need to do anything else .
What im asking is , is that the way to do the pigtail ? and will my job work with the dx 8.4 charger.
Many thanks for any enlightenment
I also had a same problem with you but different situation. My nephew just plugged the wrong adapter on the tablet and it only can turn on while plug the right adapter on it. Battery mode is malfunction. The possibility is because of polarity switching.
Is there any solution on this instead of adding a new port just like what you did? Anyone can help me on this??
Hi all, just get same problems with my Dropad A8: not charging (works with connected charger only), both green and red LEDs light.
Replaced MOSFET as gv7294 did but with no result.
Have anyone any clues about how to check and repair standard tablet's charging circuit? I'd prefer to not use DX's charger due to its poor quality and of course due to several weeks of waiting for it.
Thanks in advance!
Replaced MOSFET as gv7294 did but with no result.
Have anyone any clues about how to check and repair standard tablet's charging circuit? I'd prefer to not use DX's charger due to its poor quality and of course due to several weeks of waiting for it.
Thanks in advance!
Hi seekbirdy
I am in the UK and sourced a good quality 8.4v lipo CCCV charger which has among other things multiple mains adapters and plug ends including one compatible with the Dropad A8 (I use it for my Haipad M7 after the charge circuit died and plugging into the mains didn't charge the battery). That way you don't have to install a new power socket as you can use the existing socket on the tablet.
Here: Conrad-uk.com:
Li-Ion charger LIC 1-2
Part no.: 510741 - 89
Manufacturer part no.: 5307232/510
http://www1.conrad-u...v=7&navi=oben_2
All you need to do is a little soldering to add two wires to bypass the charge circuit. (they connect the existing power socket to the battery). Best of all it still feeds info to the tablet so it displays the charge percentage correctly.
I have more info about how to do this but it was from a user called EatatJoes who has posted lots of the topic if you search for him on the Herotab C8, etc forum, so I will need to ask his permission to post it again.
The batteries themselves in my opinion aren't the issue most of the time - it seems to be the charge circuit that goes in these tablets. Not always the case of course.
cheers
D
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2 Posts
Sorry to say Gents, but pinouts are totaly different
I made a small investigation and found the following:
In my Apad I had "sic" SL1052 charger chip
Analog for this one is EUP8057, it is same pinout and same functioning.(Leg 4 is GND and leg 1 is Vcc)
I think you rfriend made a mistake... because TI bq2057 has totaly different pinout (leg 4 = is Vcc while leg 6 is GND)
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