T/E charging on USB

[golfnut]

I have heard that the Tungsten E charges whnever it is on the USB connection to your computer. Is this true? If so it would explain some unusual battery life...

[matrix42]

Well not sure of the T|E but does that battery icon indicate it's charging?, I have a T3 that charges off a USB mini Sync cable.

[golfnut]

The battery icon does not show charging, but it has bee a week without a charger...:D:confused:

[wvit]

It's charge through USB.

If you use launcher like zLauncher, you will see that the percentage of the battery gradually increase.

[kazuni]

You can charge using the USB just like they say here, but much, much slower than a charger (since USB does not provide full 4.2V charging, it won't trigger the charge icon)

[fastpat]

Originally posted by kazuni
You can charge using the USB just like they say here, but much, much slower than a charger (since USB does not provide full 4.2V charging, it won't trigger the charge icon)

Does the green charge light only come on when the screen is off, while plugged into the USB only, or is charging only in progress while the T3 shuts down with no activity?

Pat

[golfnut]

We were talking about the TT/E not the 3 but the same may hold true for the usb on that ... anyone have the answer, I don't have a TT/3.

[cutiepie]

you can charge your palm through USB, but be careful. It might decrease your battery life dramatically.

[ziggy]

Originally posted by cutiepie
you can charge your palm through USB, but be careful. It might decrease your battery life dramatically.

Why does USB charging affect battery life? Do you have a good explanation or a link to a website confirming this?

[cutiepie]

I am not engineering major, so honestly, I do not know. but I've heard that it is related to amps.
On the power wires, the computer can supply up to 500 milliamps of power at 5 volts through USB. However, your palm needs 1A.

hope this source could be helpful

http://www.embedded.com/internet/0003/0003ia2.htm?_loopback=1

[ziggy]

Originally posted by cutiepie
I am not engineering major, so honestly, I do not know. but I've heard that it is related to amps.
On the power wires, the computer can supply up to 500 milliamps of power at 5 volts through USB. However, your palm needs 1A.


I don't understand why that would be damaging for the battery. Could someone with more knowldedge comment on this? I have seen similar claims on other boards as well, but never saw a good explanation. It is, however, quite important to know since many TE users charge via USB.

[ziggy]

I did send an e-mail to PalmOne. Surprisingly, I got an answer within 30 min. They claim that charging via USB does NOT affect battery life.

[Gnam]

Originally posted by ziggy
I did send an e-mail to PalmOne. Surprisingly, I got an answer within 30 min. They claim that charging via USB does NOT affect battery life.

Oh well!, if PalmOne support says so then it *really* must be okay to do then! :D

[ziggy]

They would probably not mind it if battery life would be a bit shorter.....

[cutiepie]

I found this at palm one website. Mayb it's ok to charge your palm through usb. sorry ! :-)

Solution ID: 20114


Information on charging the Palm(tm) Zire handheld battery







The Palm(tm) Zire handheld has a lithium-ion rechargeable battery that is charged with the included power adapter, or through the mini-USB connector through trickle charge. However, some systems may not support trickle-charging, such as laptop computers.

We recommend using the power adapter to recharge the Palm Zire handheld. It takes three hours to charge the handheld using the power adapter. The trickle charge method can take nine hours to fully charge the handheld; therefore, this method is recommended as a supplemental charging method only.

Using the mini-USB cable simultaneously with the power brick to charge the handheld does not cause damage. However, this does not speed up the charging process.


Note: Charge the Palm Zire handheld for three hours as part of the handheld setup process.

[JohnKes]

Each USB port puts out 500mA, however, if you use a 4 port unpowered hub, the 500mA must be shared among all 4 ports. This greatly slows down charging. Also, some laptops turn off the 500mA, esp. if you set it on power save or try to use more than 500mA. The adapter puts out 1000mA.

[smoothjordan]

This is really weird. Yes, the USB does charge. Over at the Tungsten E forums at brighthand.com, it says that the trickle charge (charge through the USB) is good for the battery, and using it is almost a must. It also says there that you shouldn't drain your battery because it hurts the LiIon battery.
J-Shep