Latitude 10 USB Charging Specifications

I'd like to know this as well. If I don't have to buy a more expensive and bigger USB wall charger that provides more watts then I'd buy a smaller and cheaper one that provides up to what the Latitude 10 can draw.

Well, I connected several USB wall chargers with max outputs varying from 5W - 15W (5V @ 1A to 3A). I noticed that with all of them, they didn't charge the Latitude 10 unless it was in standby or off. That's when the power light on the bottom turns on. When the tablet is on, the battery icon says the tablet's plugged in but not charging.

Also, when I restarted the tablet while still connected to any of the USB chargers, I get a message that it detected a 5W charger and won't boot unless I disable the warning in the BIOS or connect a 30W charger. If that message is accurate then even though I have a 10W or 15W charger connected, the tablet will only draw 5W. I don't have anything to be able to measure this though.

According, this http://www.eetimes.com/design/power-management-design/4237849/USB-battery-charging--it-s-harder-than-it-looks , the USB Battery Charging 1.2 spec allows a max of 7.5W (5V @ 1.5A) to be drawn. I've also read somewhere else that 25W (5V @ 5A) is the safety limit.

Why does the Latitude 10 only draw 5W even from a 15W charger? Shouldn't it at least draw 7.5W?

Hopefully, someone from Dell can answer this.

Having the same behavior, and I am disappointed. It should be explicit that it has to be turned off to charge on USB. I stupidly went on a trip without my dedicated charger thinking USB was possible. Had to not use the machine for hours one day while it charged. I think it should at least provide working power if not charge while plugged in. That would at least allow me to work without losing more battery.

I'm disappointed to hear that the USB charging is less than what I had assumed and hoped it was. However, I am very grateful for the super fast re-charging that takes place with the regular charger. Compared to some other devices I have and have read about, this is a very nice surprise.   :-)

Since I don't have any equipment to measure the actual charge rate. I just used the change in battery level (60 Whr battery) during a period of time while USB charging from a 10 W wall charger during Connected Standby.

I calculated just under 2.5 W (5 V @ 500 mA). That's not even the 5 W the boot up message mentioned. During Connected Standby, the default configuration of a device should only drain the battery 5% per 16 hours. That shouldn't bring down the 5 W charge to half.

I tried several other 5 W and 10 W wall chargers with the same results. It's very dissapointing that the Latitude 10 only draws 2.5 W when charging from the micro-USB charging port. USB charging is all negotiated. When connected to a PC USB port, a max of 2.5 W can be drawn. When connected to a USB dedicated charging port, a max of 7.5 W can be drawn. The Latitude 10 only draws 2.5 W no matter what kind of port it's connected to.

Hopefully, this can be fixed with a BIOS update but it's likely a fixed hardware configuration and that the Latitude 10 will always draw less power than all other Android and iOS tablets out there when charging through USB.

I agree that the dedicated charger is fast, but I think it was a design flaw to connect it on the bottom. It makes it a pain to use the tablet while charging in the case. I have resorted to using it upside down with the charger stuck in the top side. It works, but not ideal. I realize the charge port is also the dock connector, and I do like the dock a lot.

I agree that finding a good location for the charger is a challenge. No matter where you put it, it is going to get in someone's way.  ;-)  Same problem with the audio out jack. But, having the ability to use the machine upside down goes a long way toward alleviating the problem for me.

As I recall, every tablet I have had has the charging port on the bottom of the device. Some of these tablets work better upside down than others though. The Dell actually is one of the better ones to use upside down because there are no stupid manufacturer's logos on the front, other than the Windows button.

Very disappointing that this is the case. Have you seen this Dell video?

The implication is pretty clear (you can charge it "just like your phone", which to me means you can use it. I also have a chat log with a Canadian Dell staffer where he confirms that it will power through the micro-USB.

OK, I just tried charging my tablet from the micro-USB for the first time. Here is what happens on mine...

(I am using my phone charger which states it puts out 1.0A)

1. When the screen is off, the white charging light is on, suggesting it is charging. The tablet is in sleep mode--not off.

2. When the screen is on, it says that the tablet is plugged in, but not charging.

I didn't leave it plugged in long enough with the screen off to see how long it would take for the battery to completely charge. It appears that it does charge the battery when the screen is off, but I am assuming very slowly. I am also curious to know if the tablet would actually run without draining the battery while it is plugged into the micro-USB.

BTW: Other tablets I am familiar with typically require more output than a standard mobile phone charger to charge their battery. For example, I have a light adapter which has two ports on it. One of the ports is a special port just for charging iPads, because they require a lot more juice than a standard phone for charging.

The problem with the Latitude 10 is that it only draws 2.5 W (5 V @ 0.5 A) through the micro-USB port no matter what charger you plugin. I've tried several 10 W (5 V @ 2 A) USB wall chargers and the Latitude 10 only charges at 2.5 W. No wonder it can't be charged while in use since with WiFi on and lowest brightness, the battery discharges at 2.5 W to 3 W when idle. That's more than it draws from the micro-USB port.

Other non-Windows tablets and smartphones I've used can draw up to 5 W to 10 W through their micro-USB port. Of course, they still charge when connected to a 2.5 W charger.

I wonder why Dell capped the charging rate to 2.5 W max? Especially when it draws more power than most Android and iOS tablets. It should detect what kind of port it's connected to and draw what it's allowed to per the USB Battery Charging specification.

I imagine the 2.5W cap is to allow the Lat 10 to be (emergency) recharged with whatever device happens to be available (cell phone charger, etc.) when your Dell charger is unavailable. It is a business device, after all. If you try to pull too much power from a cell phone charger (or any small charging device), it could overheat, get damaged, or catch fire.

I imaging a scenario where I forgot to pack, or lost, my Dell charger while traveling on a business trip. I used up most of the available battery on the plane watching movies. I could just hook the Dell up to my phone charger overnight, and be ready for the big sales presentation the next morning. I love PowerPoint!

Just a thought.

Nice sharing.

I don't understand the usage with a micro usb charger. I see the white lamp, but after several hours I have the same power level. My smartphone is charged without problems... Do I need an other charger? Technical Information from by charger: 5V with 1A.

I suggest you read through previous posts in this same thread. The issue has been discussed at length.

Bottom line: the micro USB charger feature is for emergency situations only, providing enough power to charge the battery only when the tablet is turned off. And, it is very slow. It is NOT intended to replace the normal way of charging the tablet with the power adapter.

I have read previous posts. Therefore I didn't understand that implementation. Every device is able to use micro USB charger, but not a Business Tablet... - here we need a new charger, which isn't compatible to all other. More components for the transport and more components which need resources for the production and later get useless and will be thrown away.

You are true, it charge really slow. 12h charge for 5%... - it's even for emergency situations useless.