Strange behavior of mintyboost

[Oby One]

No, I didn't make the current measurements with the 3V supply because minityboost behaved in the same way.
I don't see the point in repeating all of the above tests when it is clear that the main result will be the same.... I will get a 50% charge. I will get the same very low efficiency.

If you tell me what new information I will obtain by repeating the tests.... I will do them again tonight.

[adafruit_support_bill]

The measurements may well agree with your expectations, and that is not a bad thing. But In engineering, we prefer to work with real data when we can get it.

A 50% charge from 4 cells is similar to what others are reporting for their Android phones.
One user in that thread has reported that replacing a (possibly heat damaged) resistor has improved efficiency somewhat.

[Oby One]

very well...
I will first do the new readings for 3V and then try to see what resistor is causing problems.

After reading that other users have the same 50% charge from their mintyboost...I am more relaxed... because if other users have the same problem.... I feel that I will get to the bottom of this.... and solve it

[Oby One]

1.jpg (72.33 KiB) Viewed 2848 times

Ok I finally took the measurements.
I wanted to do a wide range of voltages so I started with 2 Volts and ended up with 5.2 V
The current consumption of mintyboost can be seen in the last column.

[Oby One]

3.jpg (29.18 KiB) Viewed 2901 times

I also made a nice graph
Here you can see in a more visual way how the current consumption increases as the supplied voltage rises.
I am sure it should be exactly the opposite, meaning the current should decrease as you put in more volts into mintyboost...because it has to raise the voltage less and less.

The red line of 0.41 Amps is the actual phone consumption
The yellow doted line is just an average of the amps consumption.

[Oby One]

Please notice the intersection between the blue and the red line, it is at about 3Volts
As predicted by the graphic the phone is not charging if the voltage supplied to mintyboost is bellow 3Volts.
I have done a small experiment now and I confirmed that even if mintyboost is working .... it doesn't charge the phone.
The charging graphic of my phone shows an almost constant charging level... but it is actually slowly decreasing.

So now you have all the possible data in the world. Please help me to debug my mintyboost.
You said earlier to try to remove some resistors... Which ones?
Tell me something....anything!

[adafruit]

hi again,

you're probably not measuring it properly, but that's not something we can provide support for - your solar measurements also do not appear correct. something in your setup is wrong. if you feel that the mintyboost is not working with your phone, you're free to return it to us for a refund - at this point you're welcome to keep it and we can also issue a refund. please email support@adafruit.com

thanks,
adafruit

[Oby One]

very nice
Bravo

You got rid of my problem simply by dismissing me as an able person to take a simple measurement.
That is so unfair.
Do you want me to videotape all my measurements?

[adafruit]

very nice. Bravo You got rid of my problem simply by dismissing me as an able person to take a simple measurement.
That is so unfair. Do you want me to videotape all my measurements?

we do not require or need that. again- if you feel that the mintyboost is not working with your phone, you're free to return it to us for a refund - you're welcome to keep it and we can also issue a refund. please email support@adafruit.com

thanks,
adafruit

[Oby One]

I know you probably hate me very much
You find me very annoying because I am not going away with my problem as others do.
It is possible that I am irritating but that is not my wish at all.
Unlike many of your customers I need my problem solved and I am not giving up until it is working ok.
There might be some cultural differences ( I being from Europe) but that shouldn't stop as from communicating ok because we are technical guys and our language is science.

Please do not treat me like an idiot. I am a very competent person and you should have noticed that by now.
If you can't solve the problem.... just say so... but don't blame it on me... or don't suppose that I am such a moron that I can't do a simple power reading. I have finished a very hard 5 year university of computers ( don't know exactly how to translate it) and I find it insulting when
you treat me like such a no good individual.

If you can, please help me to solve my problem, if you can't do that.... just say so and I will stop asking for help.

[oPossum]

You are clearly doing something wrong. It is unclear if it is a build problem and/or a measurement problem.

I did a quick characterization with an Agilent 6632A power supply, Agilent 3455A DMM and a 10 ohm 3 watt load resistor.

It works as expected. Does not get hot. Does not make noise.

This is the result...

[Oby One]

Hi
Nice graphic.It is exactly how it should be.

However :

You are clearly doing something wrong.

it is not clearly that I am doing something wrong. It is the real behavior of MY mintyboost.
Yesterday I went to a friend and repeated the tests with a different ampermeter and setup environment and the readings were the same.

What is clear, is that my mintyboost is not working correctly... and I don't know why ...or how to solve it.
I build it exactly like in the instructions said and I posted clear images with it in the hope somebody will notice something wrong.

All the advices in this thread were directed to correcting me or my test methods. None was directed to actually repair the mintyboost.

I only want to repair my mintyboost. Can someone in this world help me to do just that ?
Please!!

[yeoj4151]

OK.....lets try this again and clarify your problem because you have had a few issues corrected in this thread so lets find out whats left. What exactly is the precieved problem with your mintyboost? That it will only charge your phone 50% and you are outraged at its efficency?

[Oby One]

My problem with this device is the very high power consumption on the battery pack.
It draws way to much current .... making it very inefficient .

It is charging correctly the phone.... within the required specs of 5V and ~400ma but at a too great expense on the battery pack.

[Oby One]

First step from the repair attempt... is to remove R1,2,3,4 resistors.
I just did it now... and the phone is still charging ok. I noticed a reduced power consumtion from 1.18 to 0.96 Not a big difference... but it is something.

Now I will try to remove R5.