Surface 3 Charging

[GreyFox7]

Further disappointing events...

To refresh from earlier, when the Battery gets a little over 90% charged it starts to taper off the charge rate. that happened with the Samsung charger and at around 95% it switched to the .54A mode again. This of course is bad because its not charging at that level it's actually discharging. Other chargers may or may not behave differently. It appears there's maybe just a few levels at which it will operate and once we get into the low power mode we're doomed be cause we can't get out of it.

To prove this after it tapered off it's charge rate and discharged to 93% I fired up the Passmark test to put load on it hoping that because it had "intelligently" tapered it's charge rate it might react and be able to ramp back up if there was more demand. That did not happen we stayed at the .5A low power state and rapidly discharged under heavy load. The coffin is now nailed shut on Casual micro USB charging.

 

[Gringuito]

GreyFox, wouldn't the charge rate be controlled in the firmware? This would leave the door open to a fix for this odd behavior. It seems that you've documented a bug that forces the charge to not leave the .54A mode. To be honest I'm not sure why it drops down to .54A under load in the first place unless this is to reduce thermal loading.

 

[GreyFox7]

GreyFox, wouldn't the charge rate be controlled in the firmware? This would leave the door open to a fix for this odd behavior. It seems that you've documented a bug that forces the charge to not leave the .54A mode. To be honest I'm not sure why it drops down to .54A under load in the first place unless this is to reduce thermal loading.

At the moment I don't have a tool to see the negotiation. Tapering would seem to be clearly under the direction of the Surface/firmware/charging logic. Under load id assume the charger can say no mas no mas so they are different entry points to the condition. There doesn't seem to be a way out of the condition. so far.

My battery pack just shuts off completely (0.00A) and wont restart without disconnecting and reconnecting.

Moving onto a different charger from ASUS, but first more on tapering...

 

[GreyFox7]

Wanted to give a little more detail on the charge rate tapering when we get over ~90%

Seemed we started at 91% dropped charge rate to 5500 mw 2.0A from charger. (keep in mind some of the power from the charger is used to run the device, the rest goes to charging)
91.8% 5350 mw. 1.9A
92.0% 5260mw 1.89A
92.3% 5141mw 1.85A
92.7% 4959mw 1.80A
93.0% 4815mw 1.77A
93.3% 4697mw 1.75A
93.4% 0mw .55A
Within seconds of dropping to low power state (.55A) I kicked off the load test to try to recover. No Dice, not happening.
Test ended at 91.7% -615mw .55A

It's possible it's the charger but no matter, you can't just pick up any charger and get reliable results.
Without very close monitoring you will be caught unawares.

on to the ASUS charger...

 

[GreyFox7]

Positive results with the ASUS charger.

This is for an ASUS TF300T Transformer Tablet with powered keyboard dock. Lucky I had one of those The charger Output is 5v 2.0A or 15v 1.3A so it is perhaps a bit more capable than the average run of the mill USB charger. Obviously we're not using 15v with the Surface 3.

Il give a brief description of it's success:
First I started with the Taper measurements, taking a reading at every tenth of percent charge from 90.8% to 100%. It tapered down all the way up to 100% charge so it was perfect on that dropping from the initial 2.25A to 1.11 when it reached 100%.

I haven't yet run this charger for an extended period of time at full power so that still has to be done.

At 100% I let it sit for about 15+ minutes it continued to charge at 1881 mw while the power dropped a little from 1.11A down to .97A at which point it stopped charging completely dropping to 0 mw and power stayed around .95A for a few minutes.

Then I kicked of the Passmark test and power ramped up to a peak of 2.2A and constantly fluctuating as needed all while discharge rate remained at 0 mw. Again perfect, just what the doctor ordered.

Summary out of five "other" chargers I tried this one works flawlessly so far (still need to do that extended run) but will you be as lucky?

Later today I should receive an Anker 2.4A charger... we will see what that does.
Based on what I have seen so far it should have enough power but how will it perform... TBD.

 

[netuser]

The issue could have been avoided if they had used the Type C connector with higher power capabilities and supplied adapters for other chargers. MS said they changed to micro USB by customer demand.
Sometimes the customer is Wrong!

To all customers: Demand Type C on all future devices.

It's still early for Type C. Most people would need to deal with dongles between the Type C port and their peripherals and that would be more inconvenient. The Surface 3 design was probably already finalized and too late to make changes before it might have occurred to Microsoft engineers to consider using USB Type C.
If Type C gets popular over the next year if there are massive sales of the new 12 inch Macbook and there are tons of Type C flash drives, external hard drives, power adapters and monitors released later this year, then it would make sense to have Type C on the Surfaces released in 2016.

One thing I noticed with the Surface 3 is that the Micro USB and mini displayport ports on the same side are also similar sizes. It will be easy for people to jam a micro-usb cable into the mini displayport port and damage it. If it was all Type C ports, it wouldn't matter what you plug in or which side is up.

 

[GreyFox7]

It's still early for Type C. Most people would need to deal with dongles between the Type C port and their peripherals and that would be more inconvenient. The Surface 3 design was probably already finalized and too late to make changes before it might have occurred to Microsoft engineers to consider using USB Type C.
If Type C gets popular over the next year if there are massive sales of the new 12 inch Macbook and there are tons of Type C flash drives, external hard drives, power adapters and monitors released later this year, then it would make sense to have Type C on the Surfaces released in 2016.

One thing I noticed with the Surface 3 is that the Micro USB and mini displayport ports on the same side are also similar sizes. It will be easy for people to jam a micro-usb cable into the mini displayport port and damage it. If it was all Type C ports, it wouldn't matter what you plug in or which side is up.

If you read some of the analysis about Lightning it covers the same ground and issues. Lightning vs micro USB or Type-C vs micro USB it's the same. Micro USB is fine for phones and underpowered for tablets.

 

[mtalinm]

More charging problems here. Seems to turn itself on when you plug in the charging cable, so it doesn't really charge much unless you turn if off again.

 

[dgwoodward]

My experience has been great with the chargers I have been using. I tried with a simple USB cable plugged into an iPad charger and it did great. Keep in mind the Microsoft charger block is 13w and the iPad block is 12w so I expect to get simple results between the two. As a result I ran up to Best Buy and picked up a microUSB 12w charger with a 3.3ft USB cord and it is doing well. I plan on positioning several similar setups throughout the house and office to make sure I can charge when and where I need to. I also tried the cables plugged into a cigarette lighter power adapter also designed for the iPad and it did well in that setup as well. Since I travel a lot and usually do not like to take a ton of extra stuff with me, have the versatility of the USB cable is going to make life a lot better.

 

[GreyFox7]

My experience has been great with the chargers I have been using. I tried with a simple USB cable plugged into an iPad charger and it did great. Keep in mind the Microsoft charger block is 13w and the iPad block is 12w so I expect to get simple results between the two. As a result I ran up to Best Buy and picked up a microUSB 12w charger with a 3.3ft USB cord and it is doing well. I plan on positioning several similar setups throughout the house and office to make sure I can charge when and where I need to. I also tried the cables plugged into a cigarette lighter power adapter also designed for the iPad and it did well in that setup as well. Since I travel a lot and usually do not like to take a ton of extra stuff with me, have the versatility of the USB cable is going to make life a lot better.

12w would seem to be fine as I don't think I have seen it draw more than 11.5w under any circumstances. 10w (2.0A) clearly depends on the charger, and any less will likely be iffy at best. If it fails like some of the ones I tried you wont know it until it's too late and if it's a scenario based failure you'll be blaming the surface flakey charging when its really the charger or battery pack.

I have a 10w iPad charger... I'll give it a try.

A tablet charger will probably do better than phone charger. The danger is leading people to believe *any* charger will do. someone already made a comment the MS charger was too big and they wanted to take a smaller charger.

Scenario with small charger. You use your phone all day while you have the charger you brought plugged into your Surface thinking it will be charged. At the end of the day you see your Surface is drained and so is your cell phone. you can only charge one over night because you only brought the one charger. which one do you charge?

 

[netuser]

This looks like it could work and the description says it's only 0.4 inches thick. 3.5 x 2.5 x 0.4 inches. The OEM charger is 2.24 x 1.46 x 1.12.
So, it is longer and wider, but since it seems slimmer, it would better fit in a form fitting sleeve than the OEM charger.
http://www.amazon.com/iXCC-SMART-Capacity-Travel-Charger/dp/B00FCISKIY

 

[colvill]

I'm happy to charge mine over night. I'm also happy with the battery life so far. It took a few cycles to settle down with all the updates and loading software hurting in the first couple of days. Today I've been running full screen movies at 50% screen brightness and I'm up to 6.5 hours with 25% battery left. That's enough for me to be happy.

The advantage of the micro USB is that when travel I only need one small charger and I can find a power source at most places when I out during the day if I need it.

I appreciate all your research GreyFox7.