portable phone charging using AAA problems

[Guest dudutzu]

First I'd like to send a big THANKS to all www.modaco.com developers !

I'm having a little problem. I'm trying to make a portable charger (using AAA battery's).

Using a battery adapter, 5v regulator and couple of diodes I managed to get 5v. I've connected it to my g300 using a "custom" micro usb cable (cut one end and solder + & - to red and black wires) but nothing happen (and by that I mean it's not charging )

After a little research on the internet I fount that due to a new standard (apple like) most new phones need a short on D+ and D- pins or a specific voltage in order to work.

The components work, I tested them successfully on a few other devices plus a dumb samsung phone.

My problem is that I don't have a wall charger therefore unable to "see" what are the special request for huawei. If anybody can help or wants more information I'd be more than happy to share.

Thanks for your time and effort!

Edited July 4, 2013 by dudutzu

[Guest george109]

When you say not charging, what happens if you turn off the phone and then plug it into your charger? Does anything happen then?

If you have a multimeter, what are the current and voltage readings from the solder points between the USB cable and the diodes (+ battery etc) on the + and - wires?

[Guest akarana]

Your charger can't supply the peak inrush current when the G300 starts charging. Sorry I don't have any real numbers to tell you what you need in your charger, but,

I have a portable folding solar panel, 12 volts 4 watts that i've modified with the regulator board from a car cigarette socket USB charger. This should in theory give me 700mA on the 5 volt side, and it does charge everything else I've got, iPod, video camera, etc, except it does not charge the G300. When I plug it in the charging light flashes about once every 2 seconds, and the G300 battery -discharges- :angry:

[Guest dudutzu]

When you say not charging, what happens if you turn off the phone and then plug it into your charger? Does anything happen then?

If you have a multimeter, what are the current and voltage readings from the solder points between the USB cable and the diodes (+ battery etc) on the + and - wires?

Nothing happens even with the phone off :( . The circuit supplies 5.13v but due to the fact that it's all soldered and I'm currently unable to desolder and measure I cant say what is the exact amount of current supplied, in theory I should get 5v 1A at this moment ( for testing I'm using a wall dc convertor instead of batteries ). I'll do some desoldering tomorrow and get back with the values.

TY !

Your charger can't supply the peak inrush current when the G300 starts charging. Sorry I don't have any real numbers to tell you what you need in your charger, but,

I have a portable folding solar panel, 12 volts 4 watts that i've modified with the regulator board from a car cigarette socket USB charger. This should in theory give me 700mA on the 5 volt side, and it does charge everything else I've got, iPod, video camera, etc, except it does not charge the G300. When I plug it in the charging light flashes about once every 2 seconds, and the G300 battery -discharges- :angry:

If that is true then a "pre-charge" system would solve the problem :) still in order to do that i need more info about the "peak inrush current". But in order to measure that current i need a better multimeter :( If you or anybody has access to a multimeter that can measure that without cutting the cable (mine doesn't) can you PLEASE tell me the exact values ?

You can fix the discharging part with a diode :).

If the pre-charge is a good idea I'll keep you posted with the results,layout and components.

Thanks again for your answers.

Edited July 5, 2013 by dudutzu

[Guest akarana]

Some numbers from a regulated power supply with my G300 showing 35% charge:

Set voltage to 5.0 volts, charging current drawn by my G300 = 500mA

reduce current limit, G300 light starts flashing at 200mA, goes out at 100mA

Set current limit to 500mA, reduce voltage, G300 light starts flashing at 4.5 volts, goes out at 4.3v.

Sorry I don't have access to an oscilloscope to see what's happening when the light is flashing ...

[Guest dudutzu]

Thanks for those measurements.

I've spoken with a friend who owns a memory oscilloscope, I should get a measurement for the peak current in a few days.

When charging the dumb Samsung phone it draws 430 mA since that is in the "limits" G300 should charge :).

Can you "cap" the source at 5v & 400mA and see if its charging the G300?

How did you connect your G300 ? + and GND from the power supply whit any other modifications to the USB data pins ?

[Guest akarana]

How did you connect your G300 ?

Just + and GND, no fast charge mods.

Limited to 5v & 400mA charges OK.

[Guest dudutzu]

Damn !

There must be something else wrong ... :(

I'll give it another go :|

Thanks again !

Later Edit ( 5 hours later :)) )

It turns out that al the problems were caused by the microusb connector. I've sacrificed another cable :( and it;s now charging :D even more in order to get it charging at 1A all i had to do is short the data pins.

:D

Thank for all your awesome support !

I'm planning a wireless charging mod :D I'll keep you guys posted :D

Edited July 7, 2013 by dudutzu

[Guest george109]

Damn !

There must be something else wrong ... :(

I'll give it another go :|

Thanks again !

Later Edit ( 5 hours later :)) )

It turns out that al the problems were caused by the microusb connector. I've sacrificed another cable :( and it;s now charging :D even more in order to get it charging at 1A all i had to do is short the data pins.

:D

Thank for all your awesome support !

I'm planning a wireless charging mod :D I'll keep you guys posted :D

Hope this works well for you :)

You could also make a circuit diagram and post it on the forum, or on youtube, as i would definitely make one (if I was any good at soldering!) :P

Edited July 7, 2013 by george109

[Guest dudutzu]

Hello,

I don't thing a circuit board will be required.

For the mod I've ordered a BlackBerry bold 9700 Powermat wireless charging kit.

Because I'm not very happy with the idea of soldering wires in my phone and loosing warranty I'll try and mod a micro usb B connector (this will be the hardest part) so that it ill fit in the bounders of my silicone case.

If the usb connector mod doesn't work then I'll reconsider adding the wires directly to the phones board, still that will be an issue because it will be limited to 500 mA :( .

can't wait for the kit to arrive :D