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Hardware Hackers Reveal Apple's Charger Secrets
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."
Yay for 30-pin insanity! Kill everyone now! Condone first degree murder! Advocate cannibalism! Eat shit! Filth is my politics! Filth is my life!
Oh, John Waters...how crazy you are.
Living With a Nerd
Resistance is Futile
Is it wrong for me to get a bit hot under the collar, seeing a geek girl with such an impressive electronics workdesk?
Those little resistors probably justify the 40$ price tag of all the iPhone accessories, right?
Better keep looking.
The good, the evil and the vacuum tubes.
Right to repair our own electronics though? (Or build interface devices)?
Lots of companies do this. APC puts a RS-232 serial port on a UPS but wait! They move the pins around so you need a special cable. Cisco used to have a product called the Gigastack that used a standard 6-pin Firewire cable, but no! Pins 1&2 were shorted in the "special" cables Cisco provided.
this is my sig
i've bought iphone charging cables on ebay for $2 each including shipping and they all seem to work. via the USB and in my car. sometimes i've pulled it out a bit by accident and i get the error. put the cable all the way back in and it works.
200 Ohm resistor between the D+ and D-.
Recent iPods and Phones/Touches will use it to charge at 500mA or more. And it'll be compatible with a lot more non-Apple devices than this device is.
See "Battery Charging v1.1 spec and adopters agreement" on this page:
http://www.usb.org/developers/devclass_docs
Or search for "USB-IF charging".
How long will it be before the take down notice arrives?
Someone download the plans, and put them up on a torrent site quick.
If I were God, wouldn't I protect my churches from acts of me?
Every iPod/iPhone ships with an USB cable: i use that one together with a $5 USB charger.... Where's the problem? Why do i need to build my own charger?
So the trick to reverse engineering an Apple charger protection is to look at another third party charger and copy what they did.
The beginning is great, but that end is a complete letdown in the article.
i hate when manufacturers do crap like this to keep peripherals locked into a more profitable licensing agreement. Apples tendency toward total control is one of the things i don't like about them.
tho other manufacturers are just as bad. i will never buy a Dell for my home for the same reasons. at work we had an Out of warranty gx 270 desktop. they were know for their bad capacitors in the power supply. so lo and behold the PS goes out. i have to spec a new one. at first i thought i would hop down to the local PC store and grabe a cheap PS for like $30 would work fine.
found out that the motherboards on those dells had different pin layouts from regular boards. the connector was the same as your usual PS but the lines were scrambled. if you plugged in a PS from the PC store you would fry the mobo. thus i would have to get a new PS from the dell store at a cost of $115 ..
we opted for a used PS from a 3rd party supplier for $30 instead.
wish companies would back off and be more open. the way things seem to go we're heaed back to the old at&t days when it took a court action just to add a funnel to your telephone handset http://en.wikipedia.org/wiki/Hush-A-Phone/
But the shown resistors don't look like the standard micro-USB connector. So is Apple breaking it's prommisses? Or am I missing something?
Doesn't it just use micro USB like all the other new phones?
I thought that the EU had forced all of the cell phone makers to adopt micro USB for charging and that they had complied by adopting the standard everywhere (not just in the EU).
I probably don't need to make this point here on /., but I think this is a great development. The convenience and cost saving to me as a consumer are substantial.
Has Apple managed to avoid this?
than any company that makes products with custom dongles to interface/charge their batteries? All I see is that Apple found a way slightly more clever than just making a unique connector shape...
Magic doesn't work in my presence. My power of disbelief is too strong.
Most third party chargers I see for Apple hardware are Chinese knock-offs purchased for under 20$ from eBay. I somehow doubt these manufacturers signed anything.
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
Monoprice had (has?) iPod/iPhone USB cables for 0.69 (USD). I picked up 6 a few weeks ago. (They had a limit of 6 per order). The cheapest I could find them in a store around here was ~ 10 (CND). Even with the shipping buying the six from Mono was cheaper.
K Man
Yeaaahhhhhh
Signed, Randall Munroe
She did a great job explaining things in the video and her webpage (that is her's righ?) is very clear and even showed how she got the voltages - she didn't label them but there was a clear Ohm's Law calculation there for the voltage dividers.
RIP America
July 4, 1776 - September 11, 2001
In this case, "based on the micro-USB connector" most likely was interpreted by Apple to mean "one end plugs into USB". I mean, that's based on USB, right?
In other words, Apple in effect confirmed they were entirely giving up on Firewire. :-)
If the game could be won only by getting highest sales numbers, Apple would have given up on Macs 3 decades ago.
They sell an adapter for $90 :)
Read the USB battery charging specification, you clods. You've probably never heard of it because it's relatively new and isn't covered by your dead-tree book you picked up at the local library, but it's what most manufacturers follow.
the project to And shE ran while the project come Here but now
So you either have your device set to draw a fixed amount of power (current) and limit your options to *1*, or you develop some simpler way to tell the device how much power (current) a device can demand from any given charger.
If current is within normal limits, supply +5V on the +5V line. If current exceeds normal limits, supply 0 V for a split second. The device ramps up the current it can draw until the charger starts cutting out and then steps down the current.
We all love to call out Apple when they design deliberate incompatibility into their devices, but there is a perfectly valid technical reason for what Apple is doing here, and, in fact, they are following a USB specification (which LadyAda unfortunaterly didn't even test).
Without data communications or when suspended, devices may legally draw no more than 2.5mA from a host, which is useless for charging. In fact, even if you're generous and pretend they're connected, devices are not allowed to draw more than 100mA without negotiating for a higher current, which requires actually talking to the host, and 100mA is still too little to charge properly. 500mA is the maximum allowed by the USB spec, but devices must negotiate it (there may be too many devices on the bus for negotiation to succeed).
Before there was a spec for "dumb" USB chargers, Apple used the resistors as a sentinel to avoid drawing too much current from undersized chargers in order to avoid damaging the host. This is a hack, but it works, and honestly, we're smart enough to figure out a couple resistors on the data lines. It's not like they're using crypto auth on the charger. They have a perfectly valid reason to do this. Devices which charge from "dumb" chargers aren't following the spec, though this is a common industry practice.
As it turns out, the USB-IF came up with a USB Battery Charging spec. The spec is long and boring, but it boils down to: short together the data lines (no resistors required) and you indicate that you're a dumb charger that can supply anywhere from 0.5A to 1.5A.
Guess what happens when you short the data lines of an iPhone 3G and supply 5V. Did Apple just follow a standard? Incredible!
(Yes, I'm not following the USB spec there by in turn using a USB cable to supply the 5V and not negotiating over its data lines. I didn't feel like grabbing a dedicated 5V PSU for the shot, so sue me.)
that they are not doing it the usb battery charging way:
https://secure.wikimedia.org/wikipedia/en/wiki/Universal_Serial_Bus#Power
comment first, facts later. http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm
How about some sort of web page with a description, instead of having to sit through a tedious video?
I've been trying to deal with this EXACT issue for awhile now.. Thank goodness she had the radness to put up a great video about it. THIS is full of 'win'.
PS - geek girls are awesome. Lady Ada and Jeri Ellsworth are my idols. Throw down a little Sarah McLachlan & my gf and my world's complete.
Geeks are also awesome regardless of gender. Though I prefer the lack of a male ego, it's annoying to navigate.
I thought this girl was supposed to know what she was talking about? Take a large gauge, solid core wire and connect the positive and negative terminals directly. You'll get a lot more than 1amp. Of course, the battery will probably melt. Maybe it's not safe to draw 1amp, but it's certainly possible.
A prom-miss, is that what I think it is ?
I'm not a coward by any name.
So is Apple breaking it's prommisses?
Now we know what username Gollum posts under.
"Science is a tribute to what we can know although we are fallible" -Jacob Bronowski
I suppose that was subtle attempt at humor. Anyway, the device used 4 batteries in parallel to generate 5 V and .5 amps. If you connected them in serial you will get more current, but cannot generate 5 volts.
... so why did they need to impose NDA's on everyone who makes these things? Yes, I understand there's a technical reason to build them this way, but why all the secrecy about it? It's hard to imagine any answer other than "we want to make more profit on cables by limiting competition".
A couple of resistors and Apple thinks they can sue anyone that makes a knockoff. http://www.usatoday.com/tech/news/2010-07-29-appleknockoff29_ST_N.htm This needs to be resolved in court so Apple can be forced to pull their heads out of their a-pods.
Is today bizzarro day?
from 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
to 45 2F 6E 40 3C DF 10 71 4E 41 DF AA 25 7D 31 3F
RTFA FFS! Her device uses 2 batteries (2.4-3v depending on chemistry) a chip and inductor etc to generate 5v to charge apple devices. She needs to convince the device to draw 500ma not 1A. On top of that, the method that worked on iPods stopped working on the iPhone 3Gs, so she needed to determine what resistor values (voltages) were required to convince the iPhone to charge, and draw 500ma.
Why yes, I *AM* new here. Why?
That has to be one of THE most useful sites on the web I've seen in a while. BOOKMARKED! Someone mod this guy up please!
This is considered reverse engineering now ? The only knowledge required to understand what is going on is Ohms Law ..
Why is it that Americans pronounce the word "solder" as if it were spelled "sodder"?
The author is very mistaken in their belief that AA and AAA batteries cannot deliver 1 ampere. NiMH and lithium batteries can provide several amperes of current.
It would seem that Apple's AC chargers for MacBooks have a serial prom or similar with a serial
number:
AC Charger Information:
Connected: Yes
ID: 0x0100
Wattage (W): 85
Revision: 0x0001
Family: 0x00ad
Serial Number: 0x00b2fce8
Charging: yes
But, perhaps the FCC should ban nonsense like this.
Open up the connection details, and perhaps even enforcea 'standard' so we don't have 15 kinds of connectors when all they really do is charge and send data back and forth.. I mean come on, does everyone really need their own damned custom connector? Why cant regular USB connectors work for everyone when they are USB on the other end anyway?
---- Booth was a patriot ----
Proprietary connectors are NOT "clever", they're generally asinine and should be considered criminal unless a DAMNED fine case can be made each time.
Sometimes it's (literally) criminal to use standard connectors. Example: Antenna connectors of type-approved devices (WiFi, cellphone, etc.). The radio regulatory bodies of a number of countries required the manufacturers to use proprietary connectors (and not sell them generally) to make it difficult for users to attach high-gain directional antennas or external signal boosters that might make the device exceed the country's emitted signal levels. (Of course the manufacturers had a financial disincentive to build models with standard connectors for other markets. So things were hard for modders until the inevitable marketing of mating connectors by third parties.)
Of course that isn't the situation with Apple's charging system. But just thought I'd mention it in case anybody was fuming about a radio device.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
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.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
" If you don't put these secret resistors on the data lines too, you get the dreaded Charging is not supported with this accessory" Ive got one of those official Apple iPod Hi-Fi docks and i still get this with my ipod touch.
In Google we trust.
parallel, not series. in series, you'd get 6v with the current sourcing capacity of one battery. in parallel, you'd get 1.5v with the current sourcing ability of 4 batteries.
See:
http://pinouts.ru/PortableDevices/ipod_pinout.shtml
http://en.wikipedia.org/wiki/Dock_connector#Apple_30_pin_dock_connector
In addition to USB signals, the dock connector provides, Left/Right Line in/out, Control signals to/from accessories like radio clocks, Video out, S-Video Luminance, S-Video Chrominance output, VGA out and it also used to provide firewire data signals on older iPod models.
Jesus was a compassionate social conservative who called individuals to sin no more.
The article talks about pullups and pulldowns all the time. I've read the article at http://en.wikipedia.org/wiki/Pull-up_resistor, but I still don't quite get what this means in the context...
What do they mean by "Hmm, Looks like we need to have two pull ups after all. We made a new version that now had either a pulldown or pullup on the D+ line"
Being as all these portable devices are part of interstate trade and an integral part of our lives, the federal government does have jurisdiction. Just like they can mandate how wide interstate roads are, or that we all use the same parameters on the power grid. One company cant decide to run 75hz at 190v for fun.
No, they don't need to go further then just mandating interoperability...
---- Booth was a patriot ----
If my memories were correct, Dell's now using standard ATX pinouts, since it has switched to P4(long time ago). Optiplex GX 270 is a P4 machine so I think you're fine with a 3rd party off-the-shelf PSUs(if you could find one that fits to that formfactor).
O.k., I checked out that link, yes she's smart, but it seems to me that "ravishing looks" is a slight exaggeration. She's definitely attractive, but what really stands out is not her super-great looks, but rather her prominently carried, very voluminous breasts. Not that there's anything wrong with that...
Tried this on my iphone and my ipad to fix my wires not working issue. Worked without issue.
http://www.huanix.com/2009/06/20/iphone-2g-3g-fix-this-accessory-is-not-made-to-work-with-iphone/
The legal and marketing geniuses* at Apple probably will construe that to mean, "we'll start thinking about developing the iPhone 5 with a micro-USB socket in 2010."
* Tongue in cheek...
"We are Microsoft. You shall be assimilated. Competition is futile."