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jrguy8
14-07-2007, 05:34 PM
why is it that ordinary chargers or other cellphone usb chargers (motorola,etc) won't work with xda's and htc smartphone? does anybody know what's the difference?
CameoTabby
15-07-2007, 12:01 AM
why is it that ordinary chargers or other cellphone usb chargers (motorola,etc) won't work with xda's and htc smartphone? does anybody know what's the difference?

USB Chargers for HTC phones and many other WM phones have both ping 4 and 5 grounded, while it is simply no connection to anything on Motorola or Blackberry chargers. So, they look the same but internal connections are different.
jrguy8
15-07-2007, 11:56 PM
pin 4 is NC and pin 5 is ground as shown in this site
http://www.networktechinc.com/technote.html
do you mean they are both connected to each other?so pin 4 has use on those devices.
CameoTabby
16-07-2007, 12:18 AM
pin 4 is NC and pin 5 is ground as shown in this site
http://www.networktechinc.com/technote.html
do you mean they are both connected to each other?so pin 4 has use on those devices.

Yes, in fact, many WM devices, including HTC, and ASUS actually use mini-A as charger. Look closely at the spec published by the manufacturers. They only specify USB mini-B as sync port or USB host, but not the charger port.
We assume it's USB mini-B, because it looks like it and the plug goes in well.

Take a look here. http://www.hardware-bastelkiste.de/index.html?usb.html#miniusb

while mini-A and mini-B look almost the same, can be interchangable in many cases, but, they are different.

When grounding pin 4 (with pin 5), your WM device knows it is not connect to a computer to exchange data (ActiveSync or otherwise), so the battery can open up to accept higher current from the charger without the worry about interfere with data flow.