Tablet with no usb port recharging method?

[oszkar]

Hello!

I have a 9,8in tablet with no usb jack inside, removed because it broke and it was unusable.
I have stripped the end of a USB cable and now have in front the wires that compose the cable, can i charge somehow the tablet without the mini usb port?
Thank you!

 

[oszkar]

Are there any contact points inside where I can solder two wires that would further pass to a conector that I will connect the usb cable with a compatible connector at it's end?

 

[oszkar]

Here are some pics of the usb port emplacement where it is to be put in place! It looks to me that pin 2 shows some exfoliation! Do I need that pin, is it the 5 Vpin? I am asking because i have several 5v adapters with amperages from 85 to 450mamp! IF I could fit two thin wires that were used for very fine works(that I have at hand) and a female plug at the end than I could charge the tablet by fitting a male plug to it every time that would be soldered to the wire of the charger delivering the curent necesary to charge the thing! Thank you!

 

[Mooly]

Hi oszkar.

Right... so its broken/missing. As far as I can tell the 5 volts input is on the two outer connections. As best as I can (because they are so small) I measured continuity on my Acers tablet charging lead from outer USB pins (which are the 5 volt) to the outer two pins on the tiny tablet USB plug. You should be able to determine which is negative on the tablet just by measuring continuity to other obvious grounds.

 

[oszkar]

I am having some 1,2A chargers aswell on the 5v, I am thinking wouldn't it be a thing to connect the charger to the battery leads? or does it have current regulators onboard for what electricity gets to the battery so that makes this a no to be done to the battery? If not I am checking up the +/- on the usb leads and an adapter as I said, 1,2A/5V! Till then I am lookin for a service sheet with the description of the power charging unit so that I get the info on the values of the transformer to get it right for the tablet!

 

[Mooly]

No, you mustn't connect to the battery directly. That would destroy the battery and there would be real safety risks to. All of the charging circuitry is on the tablets main PCB. All you need to do is apply 5 volts from a sufficiently high enough rated PSU to the micro USB port.

 

[oszkar]

Ok, so I hand two chargers 1. 6 V / 1200 MA 7.2 VS and 2. 4.6 V / 800 mA!

 

[Mooly]

You could add a series power diode to the 6 volt one to bring it closer to 5 volts. Something like a 1n5401. 4.6 volts is getting a bit to low and 800ma may not be sufficient.

Its important that whatever PSU you use is regulated. You don't want the voltage going over 5 volts or so at light loading.

 

[oszkar]

Transformer 1.

 

[oszkar]

Transformer 2.

 

[oszkar]

how about having applyed the two wires of the usb wire pluged into my usb port of the pc? Would that save the situation for now?

 

[Mooly]

Yes, I think you probably could use a USB socket from PC. The other PSU looks OK but confirm it is regulated... That the output is correct off load.

 

[oszkar]

Ok! It works! I stareted it! Here is a pic atached to it! Thank you!

 

[Mooly]

Well done 🙂 Looking good.

 

[oszkar]

Thanks, problem solved, I have soldered on the marginal pins right and left tho wires + and - and connected it to + and - , red and black of the wires contained in the sleeve of the wire that composes the USB cable! Works very good! Thread closed!

 

[Mooly]

Your welcome, pleased you got it up and running.