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Jason B

macrumors 6502
Original poster
May 21, 2010
363
32
Does this exist anymore? it used to, see here:

http://justanotheriphoneblog.com/wordpress/iphone-software/monitor-your-iphone-battery-life

snap-134238-thumb1.jpg


Yes, I'm jailbroken if that helps.
 
The reason I asked about this is because I notice when i charge my Iphone4 in the car, is takes FOREVER to charge! When I use the wall charger, it goes super fast. I want to know what's going on.
 
I got a car charger that can charge my ipad and iphone in the car and that charges faster then my wall charger at home. At home when i do use the ipad charger it also charges faster the iphone.
 
I got a car charger that can charge my ipad and iphone in the car and that charges faster then my wall charger at home.

This is typically the case. AC->DC conversion circuits are the most expensive part of home chargers, so they typically exhibit a trade-off between price and current (which is directly proportional to charging speed).

Since car chargers require no conversion circuit, they typically provide much more current than home chargers, and thus charge devices faster.

OP is in an unusual situation. Jason B, are you typically using the phone when you're in the car? Playing music? GPS Navigation? Screen on? All of these would use power that would otherwise go to charging the battery. That may explain what you're seeing.
 
This is typically the case. AC->DC conversion circuits are the most expensive part of home chargers, so they typically exhibit a trade-off between price and current (which is directly proportional to charging speed).

Since car chargers require no conversion circuit, they typically provide much more current than home chargers, and thus charge devices faster.

OP is in an unusual situation. Jason B, are you typically using the phone when you're in the car? Playing music? GPS Navigation? Screen on? All of these would use power that would otherwise go to charging the battery. That may explain what you're seeing.

I can tell you now, when I use the apple home charger in my wall outlet, it's twice as fast than charging it in my car. I can charge my iphone4 from 5% to 100% in a little over an hour in the wall outlet.

In my car, it takes forver. This is what I'm using.

http://www.amazon.com/iLuv-iCC163-Micro-Adapter-Triple/dp/B002VJJLFI

It's a cigarette lighter adapter that lets you plug a usb into it.

Does it matter than I'm not using the white usb cord that came from applei for the one in the car???
 
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Ah. That explains it. USB is typically limited to 500mA, and iPhone wall chargers are 1A. If you had a cord with a cigarette lighter adapter on one end and a dock connector on the other, if it's constructed properly it will provide the full 1A (and typically a little more up to the charging capabilities of the phone). However, the intermediary USB step requires that current be limited to 500mA for compatibility with all USB devices.

This a handy chart for comparing USB (500mA) to wall-outlet charging (1A):
http://whenwillapple.com/blog/2010/07/08/charging-the-iphone-4-usb-vs-outlet/
 
Ah. That explains it. USB is typically limited to 500mA, and iPhone wall chargers are 1A. If you had a cord with a cigarette lighter adapter on one end and a dock connector on the other, if it's constructed properly it will provide the full 1A (and typically a little more up to the charging capabilities of the phone). However, the intermediary USB step requires that current be limited to 500mA for compatibility with all USB devices.

This a handy chart for comparing USB (500mA) to wall-outlet charging (1A):
http://whenwillapple.com/blog/2010/07/08/charging-the-iphone-4-usb-vs-outlet/

I'm not having any issues along these lines - but that's really good info! Thanks for sharing.
 
Ah. That explains it. USB is typically limited to 500mA, and iPhone wall chargers are 1A. If you had a cord with a cigarette lighter adapter on one end and a dock connector on the other, if it's constructed properly it will provide the full 1A (and typically a little more up to the charging capabilities of the phone). However, the intermediary USB step requires that current be limited to 500mA for compatibility with all USB devices.

This a handy chart for comparing USB (500mA) to wall-outlet charging (1A):
http://whenwillapple.com/blog/2010/07/08/charging-the-iphone-4-usb-vs-outlet/

Hmm, so, the thing I'm using is a cigarete lighter plug, and on the back of it, it has a USB port. I'm using a black usb cord that came with it, and the other end plugs into my Iphone. Are you saying if I use the apple branded usb/dock cord, it might charge faster?

I don't know what to do. I just want to be able to charge my iphone in my car as quick as I do at home. I'll buy a new one, but want to be sure it's quicker than this.
 
Hmm, so, the thing I'm using is a cigarete lighter plug, and on the back of it, it has a USB port. I'm using a black usb cord that came with it, and the other end plugs into my Iphone. Are you saying if I use the apple branded usb/dock cord, it might charge faster?

I don't know what to do. I just want to be able to charge my iphone in my car as quick as I do at home. I'll buy a new one, but want to be sure it's quicker than this.

There may be some car chargers that are better quality than others but you're not going to find a car charger that charges the phone as fast as your AC adapter at home.
 
Hmm, so, the thing I'm using is a cigarete lighter plug, and on the back of it, it has a USB port. I'm using a black usb cord that came with it, and the other end plugs into my Iphone. Are you saying if I use the apple branded usb/dock cord, it might charge faster?

I don't know what to do. I just want to be able to charge my iphone in my car as quick as I do at home. I'll buy a new one, but want to be sure it's quicker than this.

No, I'm saying the fact that you have a generic cigarette lighter -> USB adapter is the problem. If you had a cigarette lighter -> dock connector adapter you'd be good.

The specs on the exact adapter you bought say it's limited to 500mA, which is just not enough. You need at least double that to be as fast as the AC charger, and you're not going to find a generic USB adapter that can do that since it violates the USB spec. If you get a USB adapter specifically designed for the iPhone you'd be able to break the 500mA boundary. Like this one:
http://www.amazon.com/elago-Micro-Charger-iphone-Device/dp/B003ITC3KU/ref=sr_1_1?ie=UTF8&qid=1287662151&sr=8-1 that's rated at 5V/1A, double the current of yours and the same as your AC adaptor.

There may be some car chargers that are better quality than others but you're not going to find a car charger that charges the phone as fast as your AC adapter at home.

That's just not true.
 
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Mine doesn't go to USB first, it goes directly cigarette lighter -> dock connector.

However, that one should be fine. It lists a max output of 1A, which would match your home charger. That one should charge as fast as the one you use in your home.
 
Mine doesn't go to USB first, it goes directly cigarette lighter -> dock connector.

However, that one should be fine. It lists a max output of 1A, which would match your home charger. That one should charge as fast as the one you use in your home.

Ok, on that monoprice link, i don't get it.. At the bottom it's says "* Not compatible with iPad, Iphone 4, Droid and Evo". Why wouldn't it be.. Hmm
 
There may be some car chargers that are better quality than others but you're not going to find a car charger that charges the phone as fast as your AC adapter at home.

I have a usb car charger that puts out 2.1 amps so it charges faster than my home charger.

Thanks again. Is that the charger you have? And it charges just as fast as your AC adapter? Just want to make sure. I need to order a few.

Also, saw this:

http://www.monoprice.com/products/p...082602&p_id=3523&seq=1&format=3#specification

Ok, on that monoprice link, i don't get it.. At the bottom it's says "* Not compatible with iPad, Iphone 4, Droid and Evo". Why wouldn't it be.. Hmm


This charger does not work with the iPhone. I have it and the iPhone does not charge when I plug it in to it. It doesn't work because of the way it lets the device know it's there. The way the iPhone knows it is hooked up to a usb charger is by the data line being shorted (the + and - of the data are connected to each other instead of open like they would be if you plugged it into a usb port on a computer) It will work with dumb phone though.


If you want a really good car charger get this one or this one. I have the first one by griffin and am very satisfied with it. Plus with either they are usable with the iPad and any other power hungry device you may have in the future.
 
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If you want a really good car charger get this one or this one. I have the first one by griffin and am very satisfied with it. Plus with either they are usable with the iPad and any other power hungry device you may have in the future.

I bought the Griffin PowerJolt for my Iphone 4, and am having a problem.

After I plug it in error pops up and says: "this accessory is not optimized for this iPhone you may experience noise caused by cellular interference and a decreased cellular signal strength". Everythings seems to work great, except now, every time I'm listening to music or playing an app with sound and the error comes up, the sound goes away and it doesn't come back....

Also, when it's plugged in, it cuts off all the sound to my Tom Tom navigation app!! I can't stand this. Along with the ipod music from playing out of the iphone4 speaker. Please help!
 
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