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Modifying a USB cable to charge iPod without PC connection

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Man-wai Chang

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Apr 29, 2011, 10:04:04 AM4/29/11
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http://www.gizmodo.com.au/2008/07/simple_hack_turns_usb_charger_units_into_iphone_chargers-2/


+5V ---50k --- D-
|
10k
|
GND ---40K --- D+

Is this safe? Would it work?

--
@~@ Might, Courage, Vision, SINCERITY.
/ v \ Simplicity is Beauty! May the Force and farces be with you!
/( _ )\ (x86_64 Ubuntu 9.10) Linux 2.6.38.4
^ ^ 22:00:02 up 5 days 2:01 1 user load average: 1.10 1.08 1.05
不借貸! 不詐騙! 不援交! 不打交! 不打劫! 不自殺! 請考慮綜援 (CSSA):
http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa

spamtrap1888

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Apr 29, 2011, 11:32:31 AM4/29/11
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On Apr 29, 7:04 am, Man-wai Chang <toylet.toy...@gmail.com> wrote:
> http://www.gizmodo.com.au/2008/07/simple_hack_turns_usb_charger_units...

>
> +5V ---50k --- D-
>                 |
>                10k
>                 |
> GND ---40K --- D+
>
> Is this safe? Would it work?
>

Show your work -- why make people duplicate your analysis?

Man-wai Chang

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Apr 29, 2011, 11:44:26 AM4/29/11
to
>> +5V ---50k --- D-
>> |
>> 10k
>> |
>> GND ---40K --- D+
>>
> Show your work -- why make people duplicate your analysis?

I dont' wanna kill my iPod Touch... :)

--
@~@ Might, Courage, Vision, SINCERITY.
/ v \ Simplicity is Beauty! May the Force and farces be with you!
/( _ )\ (x86_64 Ubuntu 9.10) Linux 2.6.38.4

^ ^ 23:40:01 up 5 days 3:41 1 user load average: 1.00 1.04 1.05

spamtrap1888

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Apr 29, 2011, 12:06:07 PM4/29/11
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On Apr 29, 8:44 am, Man-wai Chang <toylet.toy...@gmail.com> wrote:
> >> +5V ---50k --- D-
> >>                  |
> >>                 10k
> >>                  |
> >> GND ---40K --- D+
>
> > Show your work -- why make people duplicate your analysis?
>
> I dont' wanna kill my iPod Touch... :)
>

Why not just use the two resistor dividers your link claims do work?

lsmartino

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Apr 29, 2011, 12:17:34 PM4/29/11
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On 29 abr, 10:04, Man-wai Chang <toylet.toy...@gmail.com> wrote:
> http://www.gizmodo.com.au/2008/07/simple_hack_turns_usb_charger_units...
>
> +5V ---50k --- D-
>                 |
>                10k
>                 |
> GND ---40K --- D+
>
> Is this safe? Would it work?
>
> --
>    @~@   Might, Courage, Vision, SINCERITY.
>   / v \  Simplicity is Beauty! May the Force and farces be with you!
> /( _ )\ (x86_64 Ubuntu 9.10)  Linux 2.6.38.4
>    ^ ^   22:00:02 up 5 days 2:01 1 user load average: 1.10 1.08 1.05
> 不借貸! 不詐騙! 不援交! 不打交! 不打劫! 不自殺! 請考慮綜援 (CSSA):http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa

Seems to me that this mod should work. All that this mod does is to
put some voltage in D- and D+ pins, and that voltage will never be
greater than 5V, so I don´t see why it will not work.

Just give it a try. You won´t fry anything.

John Keiser

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Apr 29, 2011, 1:15:57 PM4/29/11
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I made an iPod charger to run off 4 AA batteries using a similar divider.
Not sure why you are modifying the example given, but the values are not
especially critical. Any reason you can't measure the output?

.
"Man-wai Chang" <toylet...@gmail.com> wrote in message
news:ipegh4$qd0$1...@dont-email.me...


> http://www.gizmodo.com.au/2008/07/simple_hack_turns_usb_charger_units_into_iphone_chargers-2/
>
>
> +5V ---50k --- D-
> |
> 10k
> |
> GND ---40K --- D+
>
> Is this safe? Would it work?
>
> --
> @~@ Might, Courage, Vision, SINCERITY.
> / v \ Simplicity is Beauty! May the Force and farces be with you!
> /( _ )\ (x86_64 Ubuntu 9.10) Linux 2.6.38.4
> ^ ^ 22:00:02 up 5 days 2:01 1 user load average: 1.10 1.08 1.05

> ???! ???! ???! ???! ???! ???! ????? (CSSA):
> http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa


Jasen Betts

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Apr 30, 2011, 4:50:06 AM4/30/11
to
On 2011-04-29, Man-wai Chang <toylet...@gmail.com> wrote:
> http://www.gizmodo.com.au/2008/07/simple_hack_turns_usb_charger_units_into_iphone_chargers-2/
>
>
> +5V ---50k --- D-
> |
> 10k
> |
> GND ---40K --- D+
>
> Is this safe? Would it work?

As you're not putting more than 3.3V on the data lines it looks fine
to me.

There's a standard for power-only USB sockets.
it's basically 5V and some resistors, I'm not sure how close to it
that layout it is, I'd research and try the standard way first.

--
⚂⚃ 100% natural

Jasen Betts

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Apr 30, 2011, 5:12:00 AM4/30/11
to
On 2011-04-29, Man-wai Chang <toylet...@gmail.com> wrote:
> http://www.gizmodo.com.au/2008/07/simple_hack_turns_usb_charger_units_into_iphone_chargers-2/
>
>
> +5V ---50k --- D-
> |
> 10k
> |
> GND ---40K --- D+
>
> Is this safe? Would it work?

At initial glance it seems good, but I haven't read the whole USB
charging specification.

http://www.usb.org/developers/devclass_docs/Battery_Charging_V1_2.zip


Man-wai Chang

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Apr 30, 2011, 7:03:20 AM4/30/11
to
> At initial glance it seems good, but I haven't read the whole USB
> charging specification.
> http://www.usb.org/developers/devclass_docs/Battery_Charging_V1_2.zip

Too much information.... -_-"

Are you saying that the voltage over D+ and D- should be smaller than
2.0V and 2.5V respectively?

--
@~@ Might, Courage, Vision, SINCERITY.
/ v \ Simplicity is Beauty! May the Force and farces be with you!
/( _ )\ (x86_64 Ubuntu 9.10) Linux 2.6.38.4

^ ^ 18:57:01 up 5 days 22:58 1 user load average: 1.01 1.06 1.05

Jasen Betts

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Apr 30, 2011, 8:17:32 AM4/30/11
to
On 2011-04-30, Man-wai Chang <toylet...@gmail.com> wrote:
>> At initial glance it seems good, but I haven't read the whole USB
>> charging specification.
>> http://www.usb.org/developers/devclass_docs/Battery_Charging_V1_2.zip
>
> Too much information.... -_-"
>
> Are you saying that the voltage over D+ and D- should be smaller than
> 2.0V and 2.5V respectively?

The only maximum voltage number I saw quoted for those pins was 3.6V
I skimmed it, mostly I did searches and looked at the diagrams.

--
⚂⚃ 100% natural

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