Needs to reset before using AC adapter?

LL, unless I'm standing in a fish market, I also smell something fishy. I bought a 3rd party AC charger, 2 weeks ago, tested it out before taking it on vacation with me, and everything seemed to be fine. I returned from vacation, and installed the new version of iTunes software, and used the iPod updater. Now my AC adapter does not charge or power my 5G iPod, and the blue charging indicator light on the unit flickers rapidly. I thought I may have fried the charger somehow, until I started poking around here on the discussion groups. Reset didn't seem to work, but I still need to try a reset while the iPod is "plugged in" to the computer. I suspect Apple has made some firmware changes, and not for the better...

Anyone else having these sort of issues?

Message was edited by: pcaffyn

I have the Apple AC adaptor and have two 5G 30gb iPods in the family... I have encountered zero problems charging my ipod and then turning around and charging my daughters.... I have 1.1 on my iPod my daughter has 1.0... Both iTunes are up to date..

What about folks with 3rd party chargers? Anyone ever observe this behavior? I have read a few posts here, that mention problems with chargers from older generation iPods. I hope that this is not an indication that Apple has changed the firmware to make iPod incompatable with 3rd party and older versions of their chargers. I am using the iPod on my Windows Box, and my software version is 1.1

I believe the issue is that these "dumb" USB power adapters really just supply power and don't communicate with the 5G to tell it they are able to supply "USB high power" (500mA max) not just the 100mA default maximum. In other words the 5G is following the USB Specification: Low Bus Power devices take all their power from the bus, but no more than 100mA at a time. High-power, bus-powered devices can draw up to 500mA after they are configured by host system software, but must not draw more than 100mA until they are configured (USB Specification, Version 1.1, Section 7.2.1).

I have read that early 5G firmware did not have this issue leading me to believe Apple could someday provide a help full firmware update that allows the 5G to draw Full Power if it does not get an answer when it asks the AC adapter how much it can supply.

Meanwhile the only way I have found to begin the 5G charge cycle with any third party USB power Adapter (AC or Auto) is to force a full reset of the iPod WHILE CONNECTED.

Well I finally got my "dumb" USB charger (a Belkin F8Z009 Power pack) to work with my iPod 5G 30GB. To wake up the 5G needs to see 2.5 volts on it's data lines. The easiest way to do this is with a voltage divider made with two equal resistors. Like this:



As a poof of concept I made the device below with four 30K resistors but anything from 10K to 50K should work fine.



A more compact wake up cable could be made by cutting into a standard USB male-female extension cable and soldering in four resistors like this:



Of course if your building your own or can get your "dumb" USB charger open then the resistor voltage dividers can go inside.

Excellent!

One additional hint: This cirquitry didn't work immediately; I had to put the voltage devider bridge a little out of ballance.
I got success with the above cirquitry (4x 47K) when I connected one additional 47K resistor parallel to a bridge resistor.

Finally I use 47K-47K on one branch, and 39K-22K on the other, and pulled one (Green, I think, the one closer to GND on the USB connector) a little lower (22K to GND, 39K to +5V).

This modification is backed by the measurement that I made on a working power plug charger, here the white/green voltages were as well significantly out of ballance.
So, if you can measure the current and verify that the proposed cirquitry works for you, and shift the ballance a little if required.

JonMartin: THANKS A LOT!
-Karsten

Video-iPod and USB car charger