Charge Voltage

Question

Level 1

82 points

Charge Voltage

I was at the Apple Store yesterday afternoon. I asked their employee if the current speaker docks / clock radios that Apple sells are compatible with the iPhone. The employee told me it's a "qualified yes" with the qualification being the GSM Buzz issue. When I asked her about the charge voltage output issues I'd read about around these forums, she said that "all 30 pin iPods use a 5V charger - which SHOULD be compatible with the iPhone." She said the first versions of the iPod used a higher voltage, but since Apple switched to the flat paddle connector they have all used 5V chargers.

*Can anyone confirm (or deny) the statement that "all 30 pin iPods use a 5V charger"?*

I have seen some speaker docks at Brookstone that use the universal 30 pin connector. If this is true, that all 30 pin connectors are only outputting 5V, then those speaker docks should work with the iPhone. The nice thing was that none of the Brookstone speakers I looked at, had the GSM Buzz. I turned them on, tried to check e-mail, made phone calls, and listened to voicemails, with my iPhone right next to the speakers - no GSM Buzz. They appear to use shielded speakers in their docks.

I did not connect my iPhone to the dock, for fear they were outputting a higher voltage that may damage my iPhone.

iMac Intel, Mac OS X (10.4.10), 8Gb iPhone

Posted on Oct 3, 2007 8:34 AM

Reply

Answer 1

Oct 3, 2007 9:46 AM in response to sneirbo2k7

My chargers say 5V output on them.

Reply

Answer 2

sneirbo2k7 Author

Level 1

82 points

Oct 3, 2007 10:46 AM in response to Vincentf3

For which model / generation iPod(s)?

Reply

Answer 3

R C-R

Level 6

17,794 points

Oct 3, 2007 1:16 PM in response to sneirbo2k7

Can anyone confirm (or deny) the statement that "all 30 pin iPods use a 5V charger"?

Yes, but with one important qualification: the most accurate statement would be that "all 30 pin iPods can use a 5V charger." This is because most also can use a 12V charger. Each voltage uses different pins on the connector. To complicate things a bit, the 12 V pins are what the FireWire-based cables use to supply charging power, & not all Firewire ports supply 12 volts -- some supply up to 30 volts!

Thus, a power adaptor like Apple's iPod FireWire Power Adapter will work just fine with most iPods with 30 pin connectors, you should not use a 30-pin-to-Firewire cable to plug into any other Firewire port unless you know its voltage is limited to about 12 volts.

Reply

Answer 4

sneirbo2k7 Author

Level 1

82 points

Oct 3, 2007 1:40 PM in response to R C-R

By that qualification, would a 12V (or 8V) 30 pin iPod charger do damage to an iPhone?

Reply

Answer 5

R C-R

Level 6

17,794 points

Oct 3, 2007 3:12 PM in response to sneirbo2k7

As best as I can tell, all the chargers that display the "Works with iPhone" logo supply 5 volts to the phone, even if they are 12 volt, automotive type adaptors. This implies they use the 5 volt pins in the connector & contain step-down circuitry & (hopefully) electronic regulators to deliver a stable 5 volts to the phone. Anecdotal reports suggest the 12 volt pins (which is an assumption -- they may be designed to accept higher voltages, although I think this unlikely) are also supported by the iPhone.

As you can see, I have no definitive inside info, but if you want an educated guess (with no guarantees other than best faith effort), I would say an 8 to 12 volt charger, assuming it is from a reputable manufacturer, should be safe to use with the iPhone.

Obviously, if the phone starts to overheat or act oddly, I would reconsider!

I know you would like a better answer, but at least this is an honest one.

Reply

Answer 6

sneirbo2k7 Author

Level 1

82 points

Oct 3, 2007 3:19 PM in response to R C-R

Your input is much appreciated!

I think the smart thing to do is to wait for a "Made for iPhone" speaker dock . . . hopefully with 1 million + iPhones on the market someone will decide to shield the speakers on their speaker dock before Christmas. I know JBL is claiming the On Stage 3 will be compatible with iPhone, hopefully others will follow suit and get them to market in time for the buying season.

Reply

Answer 7

R C-R

Level 6

17,794 points

Oct 3, 2007 3:50 PM in response to sneirbo2k7

Thank you for your kind words.

Another possibility is that with so many 'not made for iPhone' products out there, some quite expensive, an entrepreneur will offer adaptors that convert many of them to more iPhone-friendly versions.

Which leads me to a fairly off-topic anecdote (but is at least technical in nature ...kinda):

In an earlier age, I ran an electronics repair shop noted for good work but a twisted sense of humor. When you walked in, you could not help noticing a sign proclaiming our business to be a combined repair shop & cafe, the latter complete with daily specials that (should have) convinced you the cafe part was a spoof. We also offered custom cable adaptors, some of which were bagged up for immediate sale. In keeping with the cafe theme, I made & bagged up a BNC to fork adaptor -- an RF connector expertly soldered to the end of a dinner fork. I never ceased to be amazed at the number of people that expressed an interest in buying it, for what reason I have not a clue.

The point (to the extent there is one) is to make sure the adaptor you buy does what you need it to do. 😉

Reply

Answer 8

Oct 3, 2007 4:22 PM in response to R C-R

Hilarious anecdote! Thanks for that one.

Reply