I have the Minty Boost V3.0 built with a 4x battery pack ( 2xserial+2xparallel giving 3.0 volts) and a htc Desire phone.
The mintyboost output is ok and it is 5 volts.
The strange behaviour can be described like this.
The charging strarts ok.. it goes up to 25% then the phone discharges all the way up to 0% then shuts down.
In the morning I find the freshly recharged battery pack completely empty.
I have a brand new 4x Sony Ni-Mh 2500mah that do very well in other devices.
The temperature of the lt1302 chip goes high ...about 55Celsius or 131 degrees Fahrenheit.
As I read from the lt1302 datasheet.. it has a normal working temperature up until 70Celsius so I should be ok....
Please put a faq
somewere in the site so people wouldn't have to ask what is the normal working temperature of the V3 mintyboost
a) in USb charging mode
b) in Ac charging mode ( the two data lines soldered together )
You have to specify this two different working modes because the output on the usb chaging mode is only about 500ma....and in Ac mode about 1000ma ( the drain is much higher and the chip gets much mor hot)
I have attached a few pictures with my minty boost board and its battery pack.
For building the battery pack I have use the instructable guide from here: http://www.instructables.com/id/Double- ... -parallel/
As specified in the guide I have used 2x 1N5817 diodes for the positive line of the battery banks. Unfortunately I didn't have another two around the house for the negative one... but I will buy some today.
I mentioned this because the diodes also get very very hot ... and I don't think this is normal.
Still .. the battery back provides a nice clean 3Volts to the mintyboost..
So what do you think its the problem ? Why my htc desire doesn't get a full charge ? ...and more important why is it discharging so fast when connected to my mintyboost?