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mintboast charging Samsung Europa I5500

by amateur_25 on Sun Mar 18, 2012 5:48 pm

HI I've built a prototype based on your design. When it's charging my Samsung, it draws a massive 1.7Amps current according to my DMM.
Is this normal for a 1200mAH battery?
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Re: mintboast charging Samsung Europa I5500

by Donziboy2 on Sun Mar 18, 2012 6:09 pm

Need to give more information then that.
How many batteries? And what kind of battery..
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Re: mintboast charging Samsung Europa I5500

by amateur_25 on Sun Mar 18, 2012 6:15 pm

2 double AA Duracell ULtra power for VIN. The battery llevel indicator suggests it is charging but whilest it's charging am pulling 1.7AMPS out of
the duracells. It's a 3.7v lithithium ion @ 1200mAH am charging
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Re: mintboast charging Samsung Europa I5500

by Donziboy2 on Sun Mar 18, 2012 7:49 pm

My first thought is that the voltage on the Duracells is dropping down to like 2v or a little less. Do a quick check and see what the voltage and current on the Duracells is during a quick charge test, if it adds up to more then 3watts then there is a problem, and its gonna take more digging.
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Re: mintboast charging Samsung Europa I5500

by amateur_25 on Mon Mar 19, 2012 7:29 am

May I ask how did you come up with 3w of power? I shall report back if I indeed discover it's drawing more than 3watts. I charged my phone up using the wall adapter yestrday.
Today is a weekday so it's important to have my phone charged.
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Re: mintboast charging Samsung Europa I5500

by Donziboy2 on Mon Mar 19, 2012 9:26 am

The minty is made to output 5v at 500mA, thats 2.5w, and you usually loose some power to the chip from efficiency. 20% is a fair estimate, so 2.5w x 1.2 = 3w
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Re: mintboast charging Samsung Europa I5500

by amateur_25 on Mon Mar 19, 2012 12:58 pm

Thanks for your help donziboy 2. I think it's working now. The output is measuring 200ma.
I actually relised where you were coming from as soon as I bothered reading the datasheet properly. LOL
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