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Hardware Hacking Power Apple Build Hardware

Hardware Hackers Reveal Apple's Charger Secrets 371

ptorrone writes "In this 7-minute video we explore the mysteries of Apple device charging. Usually, device makers need to sign a confidentially agreement with Apple if they want to say their charger 'works with iPhone / iPod,' and they're not allowed to talk about how the insides work. If you don't put these secret resistors on the data lines too, you get the dreaded Charging is not supported with this accessory. We demonstrate how anyone can make their own chargers that work with iPhone 4, 3Gs, etc."
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Hardware Hackers Reveal Apple's Charger Secrets

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  • by joostje ( 126457 ) on Tuesday August 03, 2010 @02:20PM (#33127386)
    According to wikipedia [],

    China and other countries are making a national standard on mobile phone chargers using the USB standard.[13] Starting in 2010, Apple, Nokia, Motorola, Samsung and RIM will begin making handsets with a standard phone charger based on the micro-USB connector

    But the shown resistors don't look like the standard micro-USB connector. So is Apple breaking it's prommisses? Or am I missing something?

  • Confused (Score:4, Insightful)

    by Qwavel ( 733416 ) on Tuesday August 03, 2010 @02:21PM (#33127408)

    Doesn't it just use micro USB like all the other new phones?

    I thought that the EU had forced all of the cell phone makers to adopt micro USB for charging and that they had complied by adopting the standard everywhere (not just in the EU).

    I probably don't need to make this point here on /., but I think this is a great development. The convenience and cost saving to me as a consumer are substantial.

    Has Apple managed to avoid this?

  • by TheGratefulNet ( 143330 ) on Tuesday August 03, 2010 @02:22PM (#33127436)

    posted by a bunch of guys who lack the capacity to win her.

  • by Kenja ( 541830 ) on Tuesday August 03, 2010 @02:24PM (#33127466)
    Most third party chargers I see for Apple hardware are Chinese knock-offs purchased for under 20$ from eBay. I somehow doubt these manufacturers signed anything.
  • Re:Good Lord! (Score:2, Insightful)

    by Orestesx ( 629343 ) on Tuesday August 03, 2010 @02:27PM (#33127544)
    Dude, that is busted. Do not want.
  • by betterunixthanunix ( 980855 ) on Tuesday August 03, 2010 @02:28PM (#33127580)
    Do you even have to ask? Yes, we should have a right to repair, and a right to build interface devices.

    People often talk about how wasteful Americans are and the problems of a throw-away society. If people were more willing to repair their devices, especially complex electronic devices (most of which fail because of simple and repairable problems, like a broken lead), we would be better off. Aside from less electronics in landfills (let's face it, few people actually dispose of electronics properly), people would not be spending their money so quickly, and presumable that would mean fewer debt problems (or they might just spend it elsewhere).

    Of course, we will never see anyone other than a few activists pushing this sort of mentality -- corporations have enjoyed ever larger profits because people are unwilling and unable to repair their own equipment (or to find a local repairman to do it for them).
  • Re:Good Lord! (Score:5, Insightful)

    by commodore64_love ( 1445365 ) on Tuesday August 03, 2010 @02:43PM (#33127842) Journal

    >>>but 'hot' she's not

    Come here sonny. I want to give a brief talk. I recently went to my 15th reunion, and you know those "hot" girls in my class? Well they ain't hot no more! In fact they were downright repulsive (sorry, but it was true). So might as well go for the brainy, geeky girl because that will last. The beauty won't.

    If you want "hotness" that will last, go Playboy.
    The 1995 centerfold will always be hot,
    even if the model no longer is.

  • Re:Stupid chargers (Score:1, Insightful)

    by Anonymous Coward on Tuesday August 03, 2010 @02:51PM (#33127968)

    While trollish, the parent post does have a point. Is there a practical reason that the iPhone / iPod cannot be recharged and / or synced via a simple USB mico connector interface?

  • by DNS-and-BIND ( 461968 ) on Tuesday August 03, 2010 @02:52PM (#33127982) Homepage
    Sorry to distract you from the "profit is evil" theme, but the reason consumer electronics can't be repaired in America is due to the fantastically high cost of labor there. But don't listen to me, read here []:

    Do we repair DVD players?
    Yes and no. We recognize the fact that DVD players, like most electronics, were expensive when new. Now that the format has been on the market for over a decade, the cost of players has dropped radically. Most models are less than fifty dollars with all of the features one would dream of in a player. Repairs on DVD players are only economical a small fraction of the time. We recommend Albany merchants such as Target and Radio Shack as being good places to consider the purchase of a new DVD player.

    The source is a video repair shop in flyover territory which charges $60/hour for labor. Here in China, I can get my DVD player repaired for $3-10 because the cost of labor is so low. Indeed, one of the delights of living here is you can actually get things repaired. I'm just so used to automatically buying a new electric razor, rice cooker, electric lamp, (etc) when mine breaks. Here, I can actually get it fixed! In America, don't even bother phoning the repair shop as they'll just tell you that the cost of a new unit is less than the cost of their labor.

    Don't let that put you off of blaming stupid Americans who are unwilling and unable to repair their own equipment and of course blaming those eeeeevil profit-makers. The only people who see the world the right way are a small group of activists, for example yourself!

  • Re:Good Lord! (Score:2, Insightful)

    by cgranade ( 702534 ) <cgranade@g[ ] ['mai' in gap]> on Tuesday August 03, 2010 @03:03PM (#33128194) Homepage Journal
    Grow up. The author of that blog is a real, honest person. I don't think she likely appreciates that kind of treatment. Has it ever occurred to you that Sarah may actually find your comment? That there is a person behind that picture? That Sarah may not, in fact, be writing to entertain your "nerdlust," but because she has an interest in, say, science?
  • Re:Good Lord! (Score:4, Insightful)

    by couchslug ( 175151 ) on Tuesday August 03, 2010 @03:06PM (#33128244)

    "So might as well go for the brainy, geeky girl because that will last. The beauty won't."

    ++ for extreme truthiness!


  • Re:Stupid chargers (Score:5, Insightful)

    by countertrolling ( 1585477 ) on Tuesday August 03, 2010 @03:07PM (#33128264) Journal

    Is there a practical reason that the iPhone / iPod cannot be recharged and / or synced via a simple USB mico connector interface?

    Yes... Profit!

  • by Gordonjcp ( 186804 ) on Tuesday August 03, 2010 @03:20PM (#33128516) Homepage

    How about some sort of web page with a description, instead of having to sit through a tedious video?

  • by DrgnDancer ( 137700 ) on Tuesday August 03, 2010 @03:32PM (#33128736) Homepage

    But you yourself admit to being unable or unwilling to repair your stuff, you just have access to cheap labor to do it for you. I mean sure, the American shop could work for $3-10... They wouldn't be able to pay for electricity to tell if the repairs were successful or not and they'd have to work out of a tent, but they could. The simple fact of the matter is that between the extremely small cost of electronics, and the generally quite reasonable desires of electronics repair people to be able to eat and pay their rent it's simply impractical to perform repairs on most consumer grade electronics.

    The expense involved in acquiring a decent electronics repair bench, plus the limit knowledge of electricity most people have makes self repair a sort of unavailable option.

  • Re:Good Lord! (Score:4, Insightful)

    by DrgnDancer ( 137700 ) on Tuesday August 03, 2010 @03:46PM (#33128984) Homepage

    Dude, has it occurred to you that given she has a science blog with a very nice picture of herself setup obviously next to it kinda saying "Look at me, I'm a pretty little geek girl", she probably likes the attention? I'm not trying to knock her or anything, it's a perfectly normal and reasonable thing to like attention. I also greatly doubt that she wants to have wild monkey-sex with any great percentage of her readers, I'm not saying that either. She clearly likes to be paid attention to: both for her obvious intelligence and for her equally obvious good looks. Her website gives her to opportunity for both in a very safe and impersonal way, good on her. Don't expect people to ignore that she's pretty though.

    Personally I kinda liked Ada better. I'm more of a technologist than a scientist, and I like the alt-girl look. To each their own though.

  • Re:Stupid chargers (Score:1, Insightful)

    by illumin8 ( 148082 ) on Tuesday August 03, 2010 @04:01PM (#33129250) Journal

    Is there a practical reason that the iPhone / iPod cannot be recharged and / or synced via a simple USB mico connector interface?

    Yes... Profit!

    No, actually, if you RTFA, the iPhone has 2 charging modes - one uses 500ma, which is the upper-limit of a standard USB port, and a quick-charging mode which uses 1000ma. The iPhone needs to do a power negotiation to determine if the port is capable of providing 1000ma of power. This requires some signaling.

    So, in an effort to provide a superior product that can charge twice as fast from a wall charger, but won't fry your computer by drawing too much power from it's computer port, Apple put some logic in the iPhone and some corresponding resistors in their charger.

    Or, naw, you're right, Apple just wants to charge everyone for everything...

  • Re:Stupid chargers (Score:4, Insightful)

    by Rasperin ( 1034758 ) on Tuesday August 03, 2010 @04:17PM (#33129504)
    If that was the case and it wasn't for profit, why would they require a secret contract? I get why the resistors were initially added but I'm not understanding why it needs to be a trade secret.
  • by EkriirkE ( 1075937 ) on Tuesday August 03, 2010 @04:53PM (#33130008) Homepage
    Is today bizzarro day?
  • Re:Stupid chargers (Score:5, Insightful)

    by asdf7890 ( 1518587 ) on Tuesday August 03, 2010 @05:13PM (#33130376)
    But there is nothing to stop them just drawing the 500mA if the right sort of charger is not detected. Refusing to charge at all unless the licensed parts are present is pure market control, nothing else.
  • Re:Good Lord! (Score:4, Insightful)

    by geekoid ( 135745 ) <dadinportland AT yahoo DOT com> on Tuesday August 03, 2010 @05:43PM (#33130812) Homepage Journal

    except dumb womens usually aren't any good in bed.
    Smart women are far better. However crazy women are the best, but get the HELL out when you are done.

  • Re:Stupid chargers (Score:3, Insightful)

    by The Spoonman ( 634311 ) on Tuesday August 03, 2010 @06:19PM (#33131302) Homepage
    it takes almost 8 hours [] to fully charge an iPad over a USB port. I'd rather plug it in for 5 hours to the Apple charger than wait so long

    Hmmmm...why would you be waiting? Why wouldn't you just go to sleep? :)
  • Re:Good Lord! (Score:5, Insightful)

    by shiftless ( 410350 ) on Tuesday August 03, 2010 @08:33PM (#33132656) Homepage

    Actually, it has occurred to me, as I am a personal friend of Sarah's. You may not believe me, but either way, that's somewhat besides my point. I'm sure she wants attention for her outreach work and her scientific research, but to get attention only or primarily because of one's looks is to very unwelcoming. It serves to alienate people, to denigrate them-- it's why we have terms like "sexual objectification" in our language.

    OK, this just keeps getting better and better. As I read more of your posts about this girl, I begin to see what your motivation is. You're the overprotective geek friend/wannabe lover who thinks by defending her honor on some random geek message board, you will curry favor with her and this will somehow lead to her fucking you. I'm sad to inform you this will never happen.

  • by Ungrounded Lightning ( 62228 ) on Tuesday August 03, 2010 @08:59PM (#33132838) Journal

    There was a way to do this that didn't involve unsoldering and measuring the resistors.

    Tests with an ohmmeter and visual inspection had already shown that the charger tied each D line to an independent voltage divider across the supplied voltage. This produces the (Thevenin) equivalent of:
      - a voltage source at the same ratio to the supply voltage that the lower resistor's value has to the sum of the resistors' values,
      - in series with a(n equivalent series) resistance equal to that of the two resistors in parallel.

    Measuring the supply voltage and the unloaded voltage on a D line gives the resistor value ratio. You can measure the parallel equivalent resistance by either of two methods:
      - Shut down the supply, short + and -, and measure the resistance from the D line to the shorted supply.
      - Load the D line with a resistor to ground of known value that pulls the voltage down appreciably. (In the ballpark of cutting it in half is ideal.) Measure the amount it droops (and recheck the power supply voltage in case you pulled that down a bit, too.) This presumes the pullup resistor can handle 2x the normal current and 4x the normal power dissipation, for the duration of the test.

    With those two measurements you can calculate the resistor values. If they fall near standard values it provides a sanity check on your calculations and measurements. You only have to pull 'em off if there's an additional "black box" component hooked to the D lines that might foul up your measurements.

    (Of course if you already have the tools handy, pulling off and measuring the resistors may be easier. It also lets you check that there wasn't something else hidden in the circuit that you missed.)

  • by IICV ( 652597 ) on Tuesday August 03, 2010 @10:43PM (#33133630)

    Actually, I just wanted to point out that if you RTFA (instead of just WTFV), you'll see that Lady Ada does in fact acknowledge that the USB spec says some things. Here, I'll quote it for you:

    We thought "is there a enumeration chip inside every charger?" but since thats expensive and kind of overkilly we decided instead to read up on the USB protocol (go Jan!) In particular, in her fantastic book there's a part about the low level signaling states. Since you want to get the iPod charging, but NOT make it try to enumerate, we figured that we should see if there was some sort of special state you could put the data lines into that would say "no computer is attached but there is power". Turns out there is! Its called the SEI and occurs when BOTH data lines are at 3V. For mega details, read this chapter

    And if you did watch the video, you'll notice that around 1 minute she says "for iPhones and iPods, they actually use these data lines in kinda... non-standard ways", with obvious hesitation before "non-standard".

    The USB standard can say one thing, but if actual in practice implementations vary significantly, then something that conforms to the standard in theory can be non-standard in practice.

    She's glossing over that distinction and this whole discussion by just saying "non-standard" in the video, since spending five minutes talking about this would not be conducive to the demonstration she was performing.

  • by WillDraven ( 760005 ) on Wednesday August 04, 2010 @12:17AM (#33134100) Homepage

    I would say it's more Analogue Ripoff Management, as the only "right" involved here is the right to charge you an extra ten bucks for a two dollar part.

    Oh, and it also has absolutely nothing to do with copyright. The only creative expression in this series of resistors is the creative use of bullshit scam-artistry. Maybe it falls under patents? "Method And Apparatus For Fucking Customers Via Voltage Transformations And Douchebaggery"?

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