Can use ipad charger to charge iphone?

I've been charging my iPhone 3G with the iPad charger for 1 1/2 years. It's working fine and charges the iPhone faster.

I did notice a small decrease in iPhone's battery performance, but I think that's just down to the fact that the phone is now 3 years old.

If 'clearly this IS harmful' were true, then why have I never had any problems charging my iPhone 3G, 3GS, 4, 4S using an iPad charger.

Apple's power supplies are intelligent and will not supply more current than the device can handle. In your case, I'd venture something else is causing the problem.

You can use an iPad charger with any iPhone. Or any device that can be charged from USB, for that matter. One of the few things the industry has done right is standardize the power supplied by a USB port. An iPad will need a higher current than an iPhone, so you can't charge an iPad effectively from an iPhone charger, but the other way works.

Yes, you can charge your iPhone with the iPad adapter. There's a lot of confusion about this, partly b/c Apple is mum about even basic tech specs. However, the basic issue is that the 10W spec (pretty much the only detail you can find on Apple's website) is the power output, not the voltage (as some people on this thread have said). Presumably, this is significantly higher than the power output available from the iPhone power adapter, but that doesn't matter. It "wattage" is the power output *available*. The iPhone will simply draw less current than the iPad.

Also, it says that it is compatible right on the Apple website. Quote from iPad charger website:

"Featuring a compact design, this power adapter offers fast, efficient charging and includes a 6-foot-long power cord so you can plug it in under a desk or behind the couch. It also charges iPhone and all iPod models with a dock connector."

I just recently got an iPad and have the iPhone 4, iPhone 4S, iTouch, Ipod, basically I have everything Apple makes. I can see that a lot of people are confused about chargers due to them showing watts, volts, & amps and since I have a very extensive background in electronics I will clarify all this in this post.

Chargers:

PC USB 5 Volts, .5 Amps 2.5 watts

iPhone Charger 5 Volts 1.0 Amps 5 watts

iPad Charger 5.1 Volts 2.1 Amps 10 watts

Will they all charge an iPad even when your PC shows "Not Charging" YES your PC USB will charge your iPad, but very, very slowly because it is 1/4th of what an iPad charger is so it will take 4 times longer than an iPad charger (BUT YOUR SCREEN MUST BE OFF). To test that plug your iPad into your PC USB charger before you go to bed and write down what the battery percentage is and in the morning you will see it went up. Not much, but it will go up some. Reason it says "Not Charging" when you are looking at the screen when plugged into your PC is the USB is basically powering up your screen and doing nothing for the battery.

If you use an iPhone charger it will show the iPad is charging, now look above at the numbers and you see that it is about 1/2 of what the iPad charger is so it will take twice as long to charge up your iPad using an iPhone charger. Below these are totally hypothetical numbers and not realistical and I am using them to keep it simple and understandable.

If it takes your iPad charger 5 hours to charge up your iPad with the iPhone charger it will take 10 hours to charge it because it is about 1/2 the watts and amps. Make sense? Its basically just doing the math. I have not tried to do a full charge using a USB Port on my PC, but I believe like I said doing the math it will take 4 times longer because the USB port is 1/4 the output of the iPad charger and 1/2 the output power of the iPhone charger. But remember if you have your iPad screen on the USB on your PC is just powering up your screen and doing nothing for charging the battery. To test that I would have to take a guess and say let your iPad run down to say 20% or so, turn it OFF, plug it into your USB Port and power it up after I would say at least 12 to 16 hours to see where it is at. It will charge the battery I know that for sure, but it is going to take 4 times longer.

I hope this clarifies things up for everyone on this because it is all just math with the output because they all produce 5 volts only difference is Amps and Watts and the equations for that is Volts x Amps = Watts. Apple gives you the 2.1 Amp 10 Watt charger so it won't take a day to charge your iPad due to the battery being much bigger.

Most USB Hubs produce the .5 Amps even though they have an external power supply you plug into the wall. Their are some USB Hubs that have usually 1 port that will produce the 10 watts 2.1 amps, but it will just be out of one port on the hub, so if you buy one read the specifications carefully. Car chargers are pretty much the same, so read before you purchase.

Here is the name of a USB Hub that has ONE fast charge port they call it that is the same as the iPad Charger: Symba 7 Port USB 3.0/2.0 Hub with One Fast Charging USB 2.0 Port (SD-HUB20102) if you want to charger fast and sync your iPad on your PC

If you are looking for a Car Charger that is 2.1 amps just like the Apple Charger I got a Satechi 2412ST and what is really nice about it is that it is pretty much flush when plugged in, meaning you don't have this charger sticking out of your accessory socket it is flush which is really nice if you have a cove that needs to close you can leave this in...

I know this is long, but I hope all this helps and clears things up for everyone and if you buy any USB Hubs or Car Chargers for your iPad read carefully that it produces 2.1 Amps to get the fastest charge or if you don't mind it charging slower (1/2 as fast) you can get a 1.0 Amp one.

Sure go ahead... If you can let me know the name of the Forum I would love to check it out and perhaps learn somemore things about this iPad...If you could let me know the name of the forum that would be great...

A few months back, I left my iPhone 4s charger at a hotel room in another state. I have not got around to buying a replacement so I have been using the iPad 10W charger for my phone. I have been doing this for a few months on a daily basis and have experienced no loss of battery life. No problem at all. .

However I have attempted to charge my iPad with my wife's iPhone charger- it will get it done but it takes FOREVER to finish the charge. For instance, the one time I tried to do this I plugged the iPad in at around 20% battery before I went to bed. I woke up to find the battery had only charged to about 70% overnight (7 hours) I am not sure that this would cause any damage to the batteries. I think you are safe- but who am I?

You can charge the iPhone with either the iPhone charger or iPad charger. It will charge faster with the iPad charger.

You can charge the iPad with either the iPhone charge or iPad charger. It will charge faster with the iPad charger.

Nothing will be damaged in any case.

Sorry for the incredibly late response but yes, everyone is correct, it IS fine to use both. Turned out that I was experiencing a battery flaw at the same time I started trying the switched chargers. Apple promptly replaced the iphone and since then I have used both without issue.

My bad -.-

merlin1128 wrote:

... I used an old iPhone and obtained 2 other ones and put brand new batteries in them. Altered the charger to put out more than 2.1 amps and did 50 charge/discharge cycles on one. Did the same with te other one at 1 amp, and the other at .5 amps

After that let all 3 devices sit for 3 days all at the same settings and the one that was charged at .5 Amps had the best battery capacity and the one with the altered charger was the worst? Please explain that ...

You already did, in your previous post:

"Slow. Charging your battery is best to get the most out of it"

Your words and punctuation.

"why do they sell chargers for cars and ones for motor cycle batteries?"

Because of the current draw difference between a car battery and a motorcycle battery. Since a car battery charger is more robust, it costs more than a motorcycle battery charger. Let's consider something easier for you to understand. If all of Apple's battery chargers have the same voltage output, why doesn't Apple just sell one? Because the higher wattage power adapter costs more to manufacture than a lower wattage device. I have 20 years more experience than you do and 16 of those were with Apple. Ask away; make my Danish.

"What size light bulbs do they use for an L train that ONLY has a 600 volt power source coming in?"

A couple days ago, a guy posted something about a Trifield meter, and asked how to lower the USB voltage to minimize a magnetic field. It has nothing to do with your post, except my realization than the sale of tin foil hats has increased by one.

I still do not see all the questions I put up answered. If any of you are really what you say your background is these are a no BRAINER to answer. one is a little technical I will admit.

Bottom line is over charging a battery decreases its life span. I did the test and proved it. Do I care about what any of you claim you know or do? NO.

Still waiting on the questions I asked. If u really had the background most are simple and you should know the answer instantly. Not answering them tells me all the stuff you typed is something made up.

So. Any of you experts gonna answer these simple questions based on your expertise knowledge? People reading this should be wondering if u claim what you say your knowledge is then why are they not answered. I could have got really technical but figured I would keep it simple.

You do not know about 600 volt supplies or 220V 3 phase??? This is simple stuff.

Actually, as someone reading this thread, I was interested in the discussion until you got angry, bro. I'm more inclined to listen to the calm rational people so you are kind of hurting your case by getting all defensive and attacking everybody else. Calm down and explain, man.

Merlin, you know enough to be dangerous as they say, but not enough to question yourself. Mr. Finch is correct, the iChargers ; ) are just a simple power source. The regulation is done within the device. Now, could there be an issue with the internal regulation design? Maybe, but doubtful. I can tell you there are engineers dedicated to power supply, distribution, and regulation in any decent electronics design company - I know that for a fact from the time you were 10 years old, and these guys weren't brand new at it back then. (and I bet Apple employs some pretty good ones).

Throwing out all that other stuff detracts from your intent, give it up. Mr Finch is also correct about battery chargers for cars versus motorcycles - the regualtion has to be in the charger because it's being directly connected to the battery. That's not the case with an iPhone or iPad.

If you believe your testing has found something, contact Apple - or one of the product review sites, they would be interested in such an issue and could substantiate your finding if it's valid.

Well, having tried that for a month or so:

The iPad charger kills your iPhone battery.

If hook up the iPhone to the iPad charger, the battery inside gets quite hot while charging, which is the cause of the limited capacity of the battery. Meanwhile the proper iPhone charger doesn't rise the temperate of the phone at all for me.

I'm trying now whether charging the iPhone with it's charger restored some capacity, but I think the heat pretty much irreversibly killed it.