Why doesn't the iPhone 3GS smart charge?

[WilliamG]

My MacBook Pros won't start charging until they fall below 95% charge.

If you unplug the iPhone 3GS, and then plug it in after it hits 99%, it starts charging again! I've woken up in the morning and looked at my phone and the battery has hit 99% and is charging again...

Anyone else find this behavior odd?

 

[rKunda]

A little. Though most people likely don't have their phones plugged in on their desks all day, like some people do with laptops. Maybe it wasn't considered necessary?

 

[WilliamG]

A little. Though most people likely don't have their phones plugged in on their desks all day, like some people do with laptops. Maybe it wasn't considered necessary?

It just can't be good for the phone. I'm pretty sure the iPhone 2G and 3G both smart charged. The problem is that if you leave the 3GS plugged in overnight, it charges to 100%, stops charging, and then will drop to 99% an hour later (or whenever that is), and then charges again to 100%. So there's a lot of "bit" charging going on here... Can't be good for the battery...

 

[DotComCTO]

I've never seen that happen - even with my 2G iPhone. Maybe I'm not observant enough, but both of my iPhones (2G and 3GS) go to 100% and stay there...at least that's how it seems to me!

Weird.



--DotComCTO

 

[Johnathan]

My MacBook Pros won't start charging until they fall below 95% charge.

If you unplug the iPhone 3GS, and then plug it in after it hits 99%, it starts charging again! I've woken up in the morning and looked at my phone and the battery has hit 99% and is charging again...

Anyone else find this behavior odd?

You don't know what it's actually doing, you only know what the phone is reporting that it's doing.

 

[hchavarria]

My iPhone says 100% when it's plugged in but when I unplug it's at 98% and draing real fast.

 

[WilliamG]

You don't know what it's actually doing, you only know what the phone is reporting that it's doing.

O....K.....

 

[doubleatheman]

My kill a watt meter reports a constant 1 watt drain even after the iPhone is fully charged, could be a trickle charge, or the power required to keep the phone in standby, or the inneficency in the charging process.

The iPhone itself requires 5-6 watts of power when at full speed charge, then goes to 3 watts at 80% charge, and the. 2-1 watt for the rest.

 

[OneMike]

My iPhone says 100% when it's plugged in but when I unplug it's at 98% and draing real fast.

I've started keeping my phone plugged in while at work and have never noticed this. This was with 2g. From what I see was always reported as fully charged. Will confirm tomorrow with 3gs