Apple's iPad - The AnandTech Review
by Anand Lal Shimpi, Brian Klug & Vivek Gowri on April 7, 2010 9:39 PM EST- Posted in
- Smartphones
- Mac
- Apple
- iPad
- Mobile
USB Charging
There's been a lot of discussion about the iPad's ability (or lack thereof) to charge from most USB power sources. Even among accessories, the compatibility situation ranges from relatively to completely uncertain.
Let's start from the beginning though - it isn't like you're going to be unable to charge the thing. The iPad ships with a beefy 10.71 watt (5.1 volt, 2.1 amp) USB power supply and a heartier-than-normal feeling USB dock cable. Given the device's relatively long battery life (as we've already demonstrated), it isn't like charging is going to be something you'll do more than once a day. But Apple has left the charging situation uncharacteristically vague.
We tested charging with a number of dock connector charger accessories we had, and found the state of things confusing. Let's start with the good; Apple's ultracompact USB power adapter, the one shipped with the iPhone 3G and 3GS, does charge the iPad. If you've still got any laying around, the older, larger iPod chargers that have USB charging circuitry also work. Interestingly, both of these power adapters are only rated at 5 watts.
Support for charging from accessories from 3rd parties, however, varies wildly: devices that support firewire-only charging definitely won't work - the iPad lacks that circuitry the same as iPhones and iPod Touches. Other adapters that lack Apple-specific charging circuitry also don't work. Third party battery packs also won't charge the iPad.
Car chargers are a mixed bag - Griffin's PowerJolt SE car charger, sold at the Apple Store, doesn't charge the iPad at all. However, Belkin's Micro Auto Charger (rated at 5 watts), also sold at the Apple Store, does charge. Interestingly, the Griffin has a hard connected dock connector, while the Belkin has a USB termination and aftermarket dock cable - it's likely that the iPad favors USB-based chargers rated at or above 5 watts.
The iPad is picky about its power - it's something of a connoisseur
On the desktop side, charging is even more of a mixed bag. If you've got a PC, you're probably out of luck unless motherboard supports the USB charging specification. Remember that USB 2.0 by default supports 500 mA of current at 5 volts for a maximum of 2.5 watts. From what we've seen so far, at least 5 watts is required for the iPad to charge. Newer USB ports that support the battery charging specification can supply up to 1.5 amps at 5 volts, for a maximum of 7.5 watts. From what we've seen, it's likely that 5 watts is the requirement for USB charging to work properly. Apple's iPad charging knowledge base document mentions that a "high-power USB port" is required for charging, but neglects to enumerate what computers support the standard, or what standard they're calling high-power. Apple notes that "many recent Mac computers" support the high-power USB port charging standard, and that "most PCs or older Mac computers" will charge the iPad when it's in sleep mode.
We tested with a MacBook Pro 2,1 (pre-unibody Core 2 Duo), Mac Pro 4,1 (Nehalem), Latitude XT, and desktop with an EVGA X58 SLI - none of them charged the iPad over USB while powered on or in standby. It's a step backwards that the iPad discharges while syncing, and keep discharging if you leave it plugged into a non-supported USB port. Remember to plug it back into its special beefy power supply, or you'll likely be left without a working iPad.
The iPad a Super Head Unit is Not
Unfortunately, it looks like the dock connector circuitry on the iPad does not support car head units. We tested with a JVC KD-PDR40 and an Alpine iDA-X001 (which Alpine touts was designed in part with Apple to emulate the iPod interface), and both resulted in the following notification on the iPad:
Bad news for people with aftermarket head units
The Alpine iDA-X001 showed the following:
While the JVC KD-PDR40 constantly reported "reading" as its status:
It seems that, for whatever reason, the iPod playback hardware and software playback paths are not present on the iPad. This is disappointing, especially considering the number of car enthusiasts hoping to use the iPad as a super-sized head unit. In fact, much of the initial speculation was that vehicle integration would be part of the iPad's secret sauce. Based on these results, that obviously was never the intention.
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BeAloud - Thursday, April 8, 2010 - link
The rumored new smaller iPad could solve the ergonomics flaws of the current device. I would probably be interested in getting one if these rumors are true!http://www.bealoud.com/technology/ipad-mini-rumors...
Lunarlog - Thursday, April 8, 2010 - link
I read your article and it was well-written. I do have to disagree that it is a disappointment. In fact, I find the contrary. Part of the issue is that we are coming out of an economic recession - some people are still on hold as to whether or not to part with $500 when they already have a computer. Was is the same spree as the first iPhone? No. But I wouldn't expect it to be - not in these times. I wrote two articles as well on the topic. I'd appreciate it if you would give them a glance:This article came out the day after the iPad was released:
http://www.lunarlog.com/ipad-review/
This article was written shortly after the iPad's initial announcement:
http://www.lunarlog.com/the-apple-ipad-the-good-an...
TheHolyLancer - Thursday, April 8, 2010 - link
only when a pokemon rpg comes to the ipad, either with an emulator or otherwise, will it be a gaming platform for it's targeted audience. or maybe let it double as a guitar hero / rock band instrument.of all the games one there, rts is the only one that seems to be fleshed out. fps, driving, action games involving the taps are mostly broken. only rpgs or tower defense / rts games seems to be the games that should have a better experience on touch based input. who don't want to be like a commander that directs battles via the touch interface.
Sahrin - Thursday, April 8, 2010 - link
Anand, I've got to say the Apple conversion you've gone through has really cost you a lot of respect in my eyes. I know, as an Apple fan, this won't matter to you (as facts don't). But the reality of it is, Apple is ultimately like religion. When push comes to shove, there is no quantitative difference between Apple and everything else. What it comes down to is technological laziness, and a blind acceptance of Apple as superior to everything else. Jon Stokes at Arstechnica had the same problem. He OC'ed one too many CPU's, or troubleshooted one too many oddball configurations - and something broke, he just gave up; surrended all his technological know-how and competence to the quiet, white cell provided by Apple. I don't mean to say either you or he got 'dumber' - just that, rather than "do it yourself," rather than apply your knowledge on a daily basis you've just declared yourself smart enough and handed over control and understanding of what you do to Apple. It's like the engineer who builds his own car from scratch finally going over and buying a Ford. Is there anything particularly 'wrong' with that? No. But it's a kind of ... lessening of the man to see him surrrender a passion to something because it's easier.I'm really sad to see someone as intelligent as you are (certainly smarter than I am) give yourself over to this kind of laziness. AT is one of the most trusted review sites on the web; and I hope that over time it doesn't erode the way Ars did into a whining, fawning mess.
splatl - Thursday, April 8, 2010 - link
WTFSilverBack - Thursday, April 8, 2010 - link
The IPad is junk, inflated price and virtually no feature set, why would anyone want this?No USB? WTF!
manicfreak - Thursday, April 8, 2010 - link
I also feel the same way.samirotiv - Saturday, April 10, 2010 - link
You are an ass, a hypocrite, and you're absolutely nobody. I don't think you can comment about Anand's intelligence. Your unwarranted hate towards Apple makes you feel that anybody who appreciates an Apple product is unintelligent.You say there's no quantitative difference between Apple products and other products. So can you tell me another currently existing tablet that I can buy that's half as good as the iPad? Is it the pathetic JooJoo?
If you don't want the iPad because it doesn't have some feature you think you need, then don't buy it. Vote with your money. Stop trolling. I think Anand has mentioned most of it's drawbacks in the review.
Even if a tablet as good or better than the iPad exists, just writing a favourable review doesn't make Anand unintelligent. I think the review was quite unbiased.
Your armchair psychology makes your post sound even less credible. Someone ban this clown.
BTW that was an excellent review Anand, like every other review of yours. Keep up the good work..!!
splatl - Thursday, April 8, 2010 - link
Apple said from the beginning this is not a laptop replacement it is intended to be a device between a Smart Phone and a Laptop. For all waiting for Slate to come out it is still HP crap.ds1817 - Thursday, April 8, 2010 - link
Always refreshing to read a review on Anandtech. The thoroughness and attention to detail are why I've been reading your website for 12 years now. Keep up the good work!