Charging over USB on Computer

Question

Charging over USB on Computer

When I charge my iPhone on the USB port on the side of my Apple keyboard it charges up just fine. Now if I'm on a phone call when it's plugged into that USB port, my phone doesn't charge even though it says it is and it runs off of battery. Now I'm guessing since it's plugged into my keyboard and when I make a phone call, it can't get enough power to charge from the keyboard. I haven't tried it on one of the main USB ports on the back of my iMac and I'm thinking that I'll be able to talk and charge just fine over that USB port.

PowerBook G4, iMac 20", Mac OS X (10.6.1), PowerPC 1.67GHz 1gig DDR2 RAM, Intel Core 2 Duo 2.66GHz 4gig DDR2 RAM

Posted on Oct 4, 2009 10:30 PM

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Answer 1

Oct 4, 2009 10:51 PM in response to CrashingEchelon

Apple recommends connecting an iPhone direct to a USB 2.0 port on your computer - not connected to a USB hub. Connecting to a USB port on a keyboard is considered a hub.

You will be able to use your iPhone while charging when connected direct to a USB port on your computer.

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Answer 2

Oct 5, 2009 9:40 AM in response to Allan Sampson

Thank you for answering my question that I should have known to begin with 🙂

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Answer 3

gilesjuk

Level 2

195 points

Oct 5, 2009 9:51 AM in response to CrashingEchelon

When you are using a hub there is less than the 0.5 amps of power available. When you use your phone its power requirements increase and if there's not the full 0.5 amps of power it is unlikely the phone can charge from the USB port.

Your keyboard will use a few milli amps of power from the USB port meaning there is less than 0.5 amps available.

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Answer 4

Oct 19, 2009 9:41 PM in response to Allan Sampson

I do have a further question to ask you. I plugged my iPhone 3G into the back of my iMac instead of the keyboard USB ports. While charging it shows the power bolt like it should but when I get a phone call it changes over to the power plug symbol and doesn't return to the bolt. When I unplugged it, my battery meter was lower than it was before I plugged it in. If I have iTunes open while talking on my phone, the battery status meter will lose any icon it had previously and just show a battery where the current life is at.

Also my friend has a 3GS and when his battery was getting low as we were talking on the phone he plugged it into the wall outlet. The phone showed it was charging but in the middle of the conversation his battery died.

I don't doubt your solution, but given that this happened to a friend that was plugged into an external power supply shows that there's something else in play. Maybe we both just ended up with defects in our phones.

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Answer 5

Oct 19, 2009 9:55 PM in response to CrashingEchelon

The iPhone includes protection for the battery when charging.

If the iPhone's internal temperature exceeds a designated temperature when charging, charging will stop until the internal temperature is reduced. Charging the battery alone (not using the iPhone when charging) increases the internal temperature. Using the iPhone while charging even more so, and excessive heat will cause damage to the battery faster than anything else, which is the reason for this.

Was your iPhone fairly warm to the touch when this occured?

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Answer 6

Oct 20, 2009 9:39 PM in response to Allan Sampson

Thanks.

Yes it was fairly warm to the touch and makes sense that it does that. I do hope in the future they find a way for the phone to run a lot cooler, so that I'll be able to talk while it's charging without having to worry about the battery dying. So far I'd have to say that's the only draw back on the phone is the battery issues. I'd also like to be to able to turn the phone off in order to charge it like I could on previous cell phones.

Again thanks for helping me out and clearing all this up for me.

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Answer 7

Oct 21, 2009 4:43 AM in response to CrashingEchelon

You're welcome.

Do you use a case? If so, remove the case while charging and being used at the same time. A case will prevent the iPhone from dissipating heat properly and as designed - some cases making this much worse than others.

You can charge the iPhone while it is powered off, but there is no indicator available while the iPhone is powered off. You must connect the iPhone to a power source first before powering it off.

I don't consider the iPhone having battery issues. There are many who have never used a 3G phone and all 3G phones consume much more battery than non-3G phones during use when connected to a 3G network, which is why all 3G phones include an option to turn 3G access off.

And the iPhone includes wi-fi access, which all phones don't include. The iPhone always has internet access as long as their is an available wi-fi network or cellular reception, but the lower the cellular reception more battery will be used - the same with every phone but every phone does not have a 3.5" screen that is used as much as the iPhone. The iPhone is probably used more often on average by every iPhone user than any other cell phone they have used before - and I'm not talking about calls and texts. Did you use and other previous cell phone as much besides placing and recieving calls or texting? Probably not.

The problem is battery technology has always been slow in keeping up - which isn't Apple's fault. Apple could improve battery life by using a bigger battery making the iPhone much thicker and heavier, which they aren't going to do. And a removable battery isn't going to happen either. Even though this is an option with just about every other cell phone, the far left tree and bunny huggers would come down hard on Apple if they did the same. And a removable battery is a joke IMO. You need to always carry around the spare battery in your pocket or elsewhere and always making sure both batteries are charged before leaving your home or office. How many people do you know who actually do this?

I have a vehicle charger and my iPhone is always connected to my vehicle charger when driving regardless the battery level and regardless how short the drive. I also have an external battery that I take along during a flight for watching a movie or listening to music so I'm not low on battery when landing.

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