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Some nice iPhone charge up hacking…
i need this charger urgently…….what should i do
I want to know how to get hold of that charger app!
this is just voltage division, no? what happens when the iphone stops accepting current? resistors melt?
Thanks! I just modified my 3600mAh USB UPS battery charger to make it work with my iphone 3g, and it’s working great!
It doesn’t take 4 resistors to make a 2-tap voltage divider.
3 resistors in series, from +5 to Ground:
+5 to “D-” = 47k
“D-” to “D+” = 10k
“D+” to Ground = 39k
I found that my USB charger actually put out 5.25V (not exactly 5.0V) – but it worked anyway… I got 2.7V and 2.2V measured on my unit, and it went into charge mode fine.
With 5.0V, these values calculate to give 2.44V and 2.03V output. I imagine many of these chargers are in reality a little over 5.0 V output anyway.
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