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vipergts2207

Suspended
Original poster
Apr 7, 2009
4,414
9,885
Columbus, OH
Anyone know the technical reason behind why you've never been able to turn on an iPhone with a battery that just died, but that has since been plugged in? There's always that ~5 minute window you have to wait. Conversely when my MBP dies I can plug it in and turn it on right away. What's going on here?
 
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If the battery is completely dead you risk corrupting the data if you had a power failure. Much safer to have a small charge on the battery. Now with a power failure the phone can shut down properly. The MBP probably has a backup battery. Most computers do.
 
If the battery is completely dead you risk corrupting the data if you had a power failure. Much safer to have a small charge on the battery. Now with a power failure the phone can shut down properly. The MBP probably has a backup battery. Most computers do.
Ah ok, interesting if a backup battery is the difference between the two.
 
I think it's because the MBP can run on the power from the plug but the phone can only run on battery. I have two electric shavers...one can be used when plugged in regardless of the battery's charge, and the other can ONLY be run if the battery is charged up enough, regardless of whether it's plugged in. I think this is a similar situation. Plugging in the phone only charges the battery, and doesn't actually power the phone.
 
Anyone know the technical reason behind why you've never been able to turn on an iPhone with a battery that just died, but that has since been plugged in? There's always that ~5 minute window you have to wait. Conversely when my MBP dies I can plug it in and turn it on right away. What's going on here?
It's because, even when plugged in, the phone still runs from the battery (it's not like it bypasses the battery when charging and just runs off the mains).

Discharging a battery below a certain point can damage it, plus the iPhone needs a minimum voltage to operate, so the iPhone will stay off until the battery reaches a certain minimum voltage.

Regarding the MBP, my MacBook Air has done it before - it's so dead that it won't switch on right away, so that might just be circumstancial.
 
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