Touchstone Dock: Really odd USB thing! - TouchPad General

I found out today, that if I am booted in Android, the Touchstone WILL charge my Touchpad via my MacBook Pro USB port. The tablet will show the "Home" screen in its "night stand" mode, and I will get a full charge after some time.
If the Touchpad is booted into WebOS, it won't charge when attached to my MacBook Pro USB port, as expected (it's indicated in the product's brochure).
Really odd!

its simple really.
you're a wizard.

WebOS has fail safes in place where it has to be receiving full power to charge the battery to prevent damage to it. Android does not have this. My TP shows charging anytime I connect it in android to transfers files.

HazzaBlake said:
its simple really.
you're a wizard.
Click to expand...
Click to collapse
Of Oz?

monkay01 said:
WebOS has fail safes in place where it has to be receiving full power to charge the battery to prevent damage to it. Android does not have this. My TP shows charging anytime I connect it in android to transfers files.
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Click to collapse
That's more like it, thanks!

monkay01 said:
WebOS has fail safes in place where it has to be receiving full power to charge the battery to prevent damage to it. Android does not have this. My TP shows charging anytime I connect it in android to transfers files.
Click to expand...
Click to collapse
The TP will charge from any USB source as long as it is receiving the correct switch signal (actually a voltage) on its data lines.
Currently (pun intended!) only the HP AC barrel charger has the correct switching properties "of the shelf".
There are mods to enable the use of other chargers.
It is this switching signal that allows the TP to charge at full rate (nominally 2Ah). Without it all other chargers operate at much slower and lower charge rates.
It has nothing to do with which OS is in use.
The major difference is the speed of charge and this is governed by the charger (be it AC or car charger) and its rated charging current. If it is too low and the device is in use then the battery will discharge quicker than it can be charged which kind of defeats the object of charging!
The touchstone is more interesting as it can be plugged in to any USB port and operate within the tolerances of its specification and provide an element of inductive charge based on the output of the USB port being used. But once again low current means slow charge.

pa49 said:
The TP will charge from any USB source as long as it is receiving the correct switch signal (actually a voltage) on its data lines.
Currently (pun intended!) only the HP AC barrel charger has the correct switching properties "of the shelf".
There are mods to enable the use of other chargers.
It is this switching signal that allows the TP to charge at full rate (nominally 2Ah). Without it all other chargers operate at much slower and lower charge rates.
It has nothing to do with which OS is in use.
The major difference is the speed of charge and this is governed by the charger (be it AC or car charger) and its rated charging current. If it is too low and the device is in use then the battery will discharge quicker than it can be charged which kind of defeats the object of charging!
The touchstone is more interesting as it can be plugged in to any USB port and operate within the tolerances of its specification and provide an element of inductive charge based on the output of the USB port being used. But once again low current means slow charge.
Click to expand...
Click to collapse
funny enough it will show you that its charging but most likely its not pulling any power. If you do in terminal cat /sys/power/charger/currentlimit it should show you how much power its actually pulling, and since induction is actually pulling about a 1/4 less power (lost during the induction process) your actually pulling 125mah less aka 375 mah which at that point is useless

Related

[Q] Phone doesn't charge fast enough

I spend a lot of time tethering and just using my phone with the charger on... But if I spend too much time on it the phone still dies... I look at my battery usage and even though it IS charging the graph is still going down... Any word?
Sent from my PG86100 using XDA App
Do you have it plugged into the wall or through the USB port?
The phone uses more mAh than the USB port is capable of providing if you are doing almost anything with the phone. The wall charger can have a hard time keeping up at times too.
Thaxx said:
I spend a lot of time tethering and just using my phone with the charger on... But if I spend too much time on it the phone still dies... I look at my battery usage and even though it IS charging the graph is still going down... Any word?
Sent from my PG86100 using XDA App
Click to expand...
Click to collapse
I had the same problem with my EVO and the issue seems to still exist on the EVO 3D. Essentially, as posted above, when plugged into a computer, the phone charges at a lower mA than it does when plugged into the wall. Tethering uses both the WiFi radio and the 3G/4G radio which consume more power than the charging is able to supply, hence you'll see the phone slowly die even though it is charging.
I haven't really seen a good long term solution for this. I know, in an attempt to mitigate power consumption, the CPU can be down clocked and ran at a lower speed (SetCPU common App used for this purpose and free on XDA), but not sure how significant the impact it will have on the power drain.
It really would be interesting to see some detailed stats on how much power each radio in the EVO 3D consumes when used alone and when used together.
Hope that helps!
Thanks both of you but I do charge it though the ac adapter... Its gotten to the point where I got the screen all the way down and only using 3g so it barely charges... I can't even use netflix that way
Sent from my PG86100 using XDA App
Thaxx said:
I spend a lot of time tethering and just using my phone with the charger on... But if I spend too much time on it the phone still dies... I look at my battery usage and even though it IS charging the graph is still going down... Any word?
Click to expand...
Click to collapse
Are you wifi or USB tethering?
Because wifi tethering will chew through battery like nobody's business. When tethering through wifi, you are operating both the 3G/4G radio as well as the wifi radio, and doing so pretty extensively. To boot, the 3G/4G reception where you are may not be ideal, so the radio has to try harder to maintain a signal.
I've had two other smartphones that I tethered daily with, and in both cases the battery would slowly drain even while plugged into the stock charger for the phone, so that by the end of my workday the battery would be around 30-50% despite being plugged in the whole time.
You may want to get a 3rd-party charger with a higher mA rating (something in the 1500mA range), which may help.
saltorio said:
Are you wifi or USB tethering?
Because wifi tethering will chew through battery like nobody's business. When tethering through wifi, you are operating both the 3G/4G radio as well as the wifi radio, and doing so pretty extensively. To boot, the 3G/4G reception where you are may not be ideal, so the radio has to try harder to maintain a signal.
I've had two other smartphones that I tethered daily with, and in both cases the battery would slowly drain even while plugged into the stock charger for the phone, so that by the end of my workday the battery would be around 30-50% despite being plugged in the whole time.
You may want to get a 3rd-party charger with a higher mA rating (something in the 1500mA range), which may help.
Click to expand...
Click to collapse
The charging unit on the phone will down grade to one amp even if you get a 1500 ma charger. I have a iPad charger rated st 2.1 amps and still charges as fast as the stock charger. This is built in protection. I may be wrong..
life64x said:
The charging unit on the phone will down grade to one amp even if you get a 1500 ma charger. I have a iPad charger rated st 2.1 amps and still charges as fast as the stock charger. This is built in protection. I may be wrong..
Click to expand...
Click to collapse
Ah, that's good to know.
ive never had a phone that keep keep up with charging while wifi tethering. 4g phones are especially bad because of the wimax radio
Success100 said:
ive never had a phone that keep keep up with charging while wifi tethering. 4g phones are especially bad because of the wimax radio
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Click to collapse
It kinda makes sense...if WiFi tethering and mobile network on easily will exceed the normal thereshold of over 1 amp...hence battery gets hot and chrarger is working overtime in trying to power the phone with every thing going on and charging the battery with ma usage exceeding regulated power. I never thought of it like that.to bad I cannot diet this way...
life64x said:
It kinda makes sense...if WiFi tethering and mobile network on easily will exceed the normal thereshold of over 1 amp...hence battery gets hot and chrarger is working overtime in trying to power the phone with every thing going on and charging the battery with ma usage exceeding regulated power. I never thought of it like that.to bad I cannot diet this way...
Click to expand...
Click to collapse
Yeah, it's a similar issue to what can happen is using Google Navigation:
GPS + constant data + screen + graphic rendering = drain
I picked up a 1A car charger just to help combat that, though apparently Google is working on this very issue themselves:
http://www.google.vu/support/forum/...n&fid=4cc9c887d2e027120004a7f6a622a7be&hltp=2
life64x said:
The charging unit on the phone will down grade to one amp even if you get a 1500 ma charger. I have a iPad charger rated st 2.1 amps and still charges as fast as the stock charger. This is built in protection. I may be wrong..
Click to expand...
Click to collapse
I don't think that's right. I bought a rapid charger off Ebay and definitely notice the difference from the other Samsung charger I was using. Maybe the Samsung was only rated less than 1 amp, I don't know, but this charger will take my phone from under 50% to about 95% in the half hour drive to work.
I had the same problem as the OP. Running the GPS and Nav apps for the duration of the trip would leave my phone with less juice than when I started. After the new power cord it's a few percentage points higher at least.
I bought this one. For $3 bucks I figured I couldn't go wrong since it was a U.S. seller and had high feedback.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300518663951&ssPageName=STRK:MEWNX:IT
ScottSNX said:
I don't think that's right. I bought a rapid charger off Ebay and definitely notice the difference from the other Samsung charger I was using. Maybe the Samsung was only rated less than 1 amp, I don't know, but this charger will take my phone from under 50% to about 95% in the half hour drive to work.
Click to expand...
Click to collapse
Depends o the amperage of the charger being used. Many older chargers and stock chargers from all but the most recent phones are in the 500mA to 750mA range. The data on the charger should list it's output.
A lot of USB car chargers need to be modded to get the full power out of them. They basically tell the phone that it's connected to a computer and to only take ~500mA. When you mod them, the phone will pull ~1A.
There's a thread somewhere around that talks about it and shows how to do it, I think it's in the EVO 4G forum. Basically, you short out pin 2 and 3 so the phone knows it's not connected to a computer.
Night·Fire said:
A lot of USB car chargers need to be modded to get the full power out of them. They basically tell the phone that it's connected to a computer and to only take ~500mA. When you mod them, the phone will pull ~1A.
There's a thread somewhere around that talks about it and shows how to do it, I think it's in the EVO 4G forum. Basically, you short out pin 2 and 3 so the phone knows it's not connected to a computer.
Click to expand...
Click to collapse
I thought that had to do with getting iPhone chargers to work on the every other device on Earth? Something about Apple speccing the ground differently or something?
I know that with the vast majority of older iPhone-intended chargers, they simply won't charge any other USB device I've tried (my old Xperia X10, my mom's Sony eReader, the EVO 3D, my friend's Samsung Galaxy). If they were simply being limited to 500mA, they'd still charge, just not particularly fast.
-edit-
OK, I think I found the issue (from Wikipedia - http://en.wikipedia.org/wiki/Universal_Serial_Bus):
Non-standard devices
Some USB devices require more power than is permitted by the specifications for a single port. This is common for external hard and optical disc drives, and generally for devices with motors or lamps. Such devices can use an external power supply, which is allowed by the standard, or use a dual-input USB cable, one input of which is used for power and data transfer, the other solely for power, which makes the device a non-standard USB device. Some external hubs may, in practice, supply more power to USB devices than required by the specification but a standard-compliant device may not depend on this.
Some non-standard USB devices use the 5 V power supply without participating in a proper USB network which negotiates power draws with the host interface. These are usually referred to as USB decorations. The typical example is a USB-powered keyboard light; fans, mug coolers and heaters, battery chargers, miniature vacuum cleaners, and even miniature lava lamps are available. In most cases, these items contain no digital circuitry, and thus are not Standard compliant USB devices at all. This can theoretically cause problems with some computers, such as drawing too much current and damaging circuitry; prior to the Battery Charging Specification, the USB specification required that devices connect in a low-power mode (100 mA maximum) and communicate their current requirements to the host, which would then permit the device to switch into high-power mode.
In addition to limiting the total average power used by the device, the USB specification limits the inrush current (i.e., that used to charge decoupling and filter capacitors) when the device is first connected. Otherwise, connecting a device could cause problems with the host's internal power. Also, USB devices are required to automatically enter ultra low-power suspend mode when the USB host is suspended. Nevertheless, many USB host interfaces do not cut off the power supply to USB devices when they are suspended since resuming from the suspended state would become a lot more complicated if they did.
There are also devices at the host end that do not support negotiation, such as battery packs that can power USB-powered devices; some provide power, while others pass through the data lines to a host PC. USB power adapters convert utility power and/or another power source (e.g., a car's electrical system) to run attached devices. Some of these devices can supply up to 1 A of current. Without negotiation, the powered USB device is unable to inquire if it is allowed to draw 100 mA, 500 mA, or 1 A.
Click to expand...
Click to collapse
There's also a good discussion on it here: http://superuser.com/questions/7765...connected-with-my-pc-to-charge-my-droid-phone

usb charging..

how can u disable the usb charging? even if its in mass storage mode its keeps on charging.. pls help..
What's wrong with the phone charging?
Isn't it a good thing?
Charge properly
You wouldn’t think that there is a particular technique to plugging your Galaxy S 2 in to charge – and you’d be right. However, you should pay attention to when you charge. If you’re constantly topping up your phone’s battery whenever you get the opportunity, you won’t be doing it any favours.
mulambo said:
Charge properly
You wouldn’t think that there is a particular technique to plugging your Galaxy S 2 in to charge – and you’d be right. However, you should pay attention to when you charge. If you’re constantly topping up your phone’s battery whenever you get the opportunity, you won’t be doing it any favours.
Click to expand...
Click to collapse
Who said ?????
jje
If i can find the link to a few sites ill post. But lipo batteries LOVE top up charging. Google it. Common knowledge.
Sent from my GT-I9100 using XDA App
Constant charging to 100% is actually bad for the battery, if you stop the charging at 90% your battery will live twice as long, with only a 10% drop in runtime.
I had an Motorola defy, and i am sure you could select not to charge the battery, when connected to your computer.
I'm also interested in the initial question...and my reason: if i connect my s2 with the mass-storage capable usb-port of a Samsung TV for viewing photos directly through the Media Player from the TV, i get an error from it saying too much current on usb because of the charging
so - how to avoid this?
A standard tv usb port does not provide enough power to charge the S2, you need a special adaptor that you plug you S2 charger into to provide extra power, see link below.
New Samsung TV`s don't know when, will provide more power to the usb ports so you will not need the charger in the future.
http://www.amazon.co.uk/TV-Out-Adapter-Samsung-Galaxy-G-HUB/dp/B005GCBVXM
GrandLX said:
I'm also interested in the initial question...and my reason: if i connect my s2 with the mass-storage capable usb-port of a Samsung TV for viewing photos directly through the Media Player from the TV, i get an error from it saying too much current on usb because of the charging
so - how to avoid this?
Click to expand...
Click to collapse
You guys are thinking of NiMh batteries, not Li+ batteries.
Li+ prefers a full charge, does not have a memory effect. If it stays at low power levels 10% it damages the batteries.
Li+ batteries have around 3000 to 5000 deep charge cycle, a deep charge is when you use to around 10% then charge.
It however has more than 2,000,000 micro charge cycles. Meaning you charge it at around 40%~80%
Battery has a cell life span, which means it is going to break regardless how you use it in 2 yrs time.
As for charging via TV, yes, you need a special cable, but that's for HDMI, not USB. The HDMI port is also the USB port on the phone. Standard USB Port supplies 5V 500mA, however, some Computers and Electrical Appliances with a USB port supply different amounts, depending on design.
Computers can supply 5V 1000mA, TVs might supply 5V but less than 500mA. Media Boxes might supply 5V but less than 500mA. Some USB chargers might supply 5V 1000mA but do not have signal in data+ data- lines, which causes the phone to lag while charging.
WIKIPEDIA KNOWS EVERYTHING. Wiki it, it will tell you it is true.. LOL!
so its oki if you plug the s2 to ur pc anytime and charge it anytime?
Pretty much.
I already got an adapter for connection via hdmi, but i forgot and tried to connect as mass-storage. Thought there might be a trick...

Can't charge fast enough?

Using a New Trent External charger I noticed that the phone was still losing power, just at a way slower rate than without it charging. Phone showed charging. I was using netflix via 3g at the time. Would this be expected? Not super worried as the battery charges just fine when screen is off and not in use.
How many amp output is that charger??
My phone can't keep up with the charge if I'm veiwing a movie using HDMI unless I run incredible kernel with fastcharge enabled.
7000mAh. Think 1V output?
IIRC, the stock A/C charger is 1 amp.
A lot of aftermarket chargers do not have the balls to charge the Rezound.
you may need to modify a usb cable to short the Data wires to get the full charging potential out of it.
or try one of these cables from amazon:
http://www.amazon.com/Naztech-Micro...3?s=electronics&ie=UTF8&qid=1328727460&sr=1-3
thatsricci said:
you may need to modify a usb cable to short the Data wires to get the full charging potential out of it.
or try one of these cables from amazon:
http://www.amazon.com/Naztech-Micro...3?s=electronics&ie=UTF8&qid=1328727460&sr=1-3
Click to expand...
Click to collapse
Does this cable work for sure with the rezound??
I don't need it right now with the incredicontrol running, but I ordered it just as a handy thing to have.
My new Trent works pretty well, but I wouldn't expect it to keep up with streaming vids. I found that it gives a charge to the idle phone at about 800mA, which is about the same as the stock wall charger.
Pick up battery monitor widget and you can track your plus and minus usage pretty well to decide if everything seems OK.
jmorton10 said:
Does this cable work for sure with the rezound??
I don't need it right now with the incredicontrol running, but I ordered it just as a handy thing to have.
Click to expand...
Click to collapse
Well, I'll answer my own question. The cable definitely DOES NOT force higher charging at least when using an HDMI adaptor.
If I use Incredikernel with fast charging enabled with Incredicontrol, it will actually GAIN charge while playing a full length movie through HDMI.
This morning, I flashed back to dsb 1.3 with no frills cpu control & hooked up the new cable for charging. I started with a 100% charged battery & after playing a 1 hour DVD RIP from my card, it was down to 89% charged. Using Incredicontrol, during the exact same test the battery still read 100% at the end.
Thanks for your results jmorton10. Good to know. I wonder if it's the connections inside the HDMI adapter messing with it.
Not sure why HTC can't just get this right to always pull the max possible from whatever it's hooked into!
-j
My understanding is because the MHL adapter needs the USB data pins to work properly and they can't be shorted out as mentioned above, the phone thinks it's on a USB connection and limits it's current draw to 500mA.
mjones73 said:
the phone thinks it's on a USB connection and limits it's current draw to 500mA.
Click to expand...
Click to collapse
That is definitely the problem, the battery monitor widget claims it is charging from USB even though it is plugged directly into an A/C charger.
I guess I will be flashing back to Incredikernel/Incredicontrol tonight. I do like dsb kernel slightly better as it never freezes/bootloops etc. ever on that kernel. It does stop responding occasionally on IC (requiring a battery pull) although it doesn't happen very often.
The Rezound complies with the USB charging specification. If your power source isn't compliant, it won't draw more that 500 mA (and probably less if USB doesn't enumerate, but I haven't checked). That's what the "short the USB data pins" thing is all about. Earlier USB charging spec said they should be shorted, the latest says 200 ohms. Any "USB charger" which doesn't do that isn't compliant, and shouldn't be sold as USB-anything, because it doesn't follow the USB spec. Return it to where you got it, and complain (loudly).
Regardless of how much power a charger can deliver, even if it meets spec you won't see more than about 800 mA go into the battery. There's a limit to how much current both the connector and the battery can safely handle, and the phone takes that into consideration.
Remember, the mA reported by utilities is (always?) what's going in/out of the battery. The charger would be delivering more than that (e.g. 800 mA into the battery, plus 400 mA to power a phone doing video streaming, etc.). AIR, the micro USB connector is limited to ~1500 mA, and I've never seen a battery charge at much more than 800, as reported by the kernel. Conversely, when charging from a non-USB charging spec compliant port, the phone won't draw more than ~500 mA from the port, and the battery only gets what's left after subtracting what's needed to run the phone.
Another thing which can affect charging is the cable. If you have a long USB cable using 28 gauge wire, there will be a significant voltage drop across it. USB specs say the voltage should be between 4.75 and 5.25 V, and Android seems to limit the charging current so the incoming voltage stays above 4.75V. Using 24 gauge USB cables, especially with longer lengths, can increase the charging current. Most vendors don't tell you the wire gauge used in their cables, but Monoprice does (no relation, etc.).

increase charging speed by raising voltage levels

my SGSII takes about 3 hours to fully charge. in japan, we had charging stations, where youd place a battery in a machine, and itd charge it from 10% - 70% in about 8 minutes,. and to 90% in about 15. this was because the machines used a higher current.
ive noticed the stock usb charger that comes with the S2 is a lower voltage of those compared to HTC, or say one youd buy at radio shack. yet even with a higher voltage charger, the phone still charges at the same rate. this is because the kernel controls input levels. the input levels are set to slowly take in a current, there are many reason youd want to have a slower charge.
one is to reduce salt bridge deterioration, which is ware on the battery. while this may be an issue for some who plan on keeping their phone battery for years, without upgrading their phone, or battery, for most of us a year of ware wont make a difference.
a second issue is heat, a faster charging battery generally charges warmer than a slower charging battery. however the phone will still not get as hot as a phone sitting in the sun, or playing a high graphics intensive game.
i would like to adjust the kernel to allow higher frequencies, how much of a higher frequency? well that would require bench testing. but a higher frequency indeed
has anyone played with these settings in the kernel, or done any benchtesting on the matter? id be very interested to hear your findings.
It's not possible.
http://forum.xda-developers.com/showthread.php?t=1468834
This has been asked more times than I've been able to keep count on here over the past month :-/ Answer doesn't change (unless you want to blow **** up).
so then the only way is to use an external battery charger?
because i know for a fact, an external battery charger can charge a battery very fast, ive experienced this first hand
on that link you posted, it said that the sgs2 charging limit is 650mA, but the USB charge is set lower.. has anyone raised the USB charge to 650mA? this would at least help my phone charge faster in the car, or while plugged into my laptop
soraxd said:
so then the only way is to use an external battery charger?
because i know for a fact, an external battery charger can charge a battery very fast, ive experienced this first hand
on that link you posted, it said that the sgs2 charging limit is 650mA, but the USB charge is set lower.. has anyone raised the USB charge to 650mA? this would at least help my phone charge faster in the car, or while plugged into my laptop
Click to expand...
Click to collapse
The USB charge is not set to low, the current given by that of a computer USB port is less than 650mA (500mA if i remember correctly) and also depending on the car charger the output (might) be less than 650mA. I use the same computer USB cable with an external USB charger and i notice 2 things:
1- Since the phone pulls the required current from where ever the USB is plugged in, if it has capability of providing 650mA the phone will take 650mA. And with the external USB Charger (iSound Portable Charger) i can charge the phone in 3 hours.
2- Secondly while plugged in the iSound it shows charging "AC plugged in" this is because it can provide 650mA (which is the same as the wall outlet adapter)
Actually from what I know, and correct me if I'm wrong, even using the charger that comes with the sgs2 isn't the healthiest choice for your battery because the voltage is high to cut down on charging time. The best should be by connecting to your pc
I think it is the amps of the charger what makes a difference in charging speed
Sent from my Galaxy Nexus using XDA
Jetmantrunks said:
Actually from what I know, and correct me if I'm wrong, even using the charger that comes with the sgs2 isn't the healthiest choice for your battery because the voltage is high to cut down on charging time. The best should be by connecting to your pc
Click to expand...
Click to collapse
Mistakenly pressed the thanks button, instead of the quote lol
Anyhow see if the phone is plugged in to the device that can provide as much current from 0.1A to 2.2A (from simple devices to Iphone <- they require 2.2A) the phone automatically draws the amount of current it is made to draw which is SGS2 is 650mA which is coincidentally the same as the wall outlet adapter.
I might be wrong, so correct me if i am.
I as thinking of lower the 650Ma AC rate to 450Ma or less, to allow the phone to slowly charge up overnight, with the aim of finding a rate that acheives a 5-6 hour charge time from empty.
Any thoughts? I was just thinking it should cause less heat and perhaps extend is life accordingly?

[Q] MHL charging rate on i717 unacceptable

So with the Current Widget installed I can monitor the incoming charge rates vs different usb chargers. Here is what i have found:
USB on samsung 1A charger: 10050mah
USB on computer: 4950mah
Shorted data pins usb cable on computer: 9550mah
MHL cable 2950mah max via any type of cable/charger.
This enevitably will drain the battery from 100% to below 10% within a few hours even plugged in. No marathon sessions of any type or even a casual flick if you start out below 50% remaining to begin with.
There must be a software override to force the current governor in the phone to allow the full amp in the charger be used in cases of MHL. Has this already been done? Anyone have a solution?
I dont think the current widget is accurate.
Sent from my SAMSUNG-SGH-I717 using XDA
accuracy
The Current Widget states support for the galaxy note, but only shows the current flow while charging (ie it will not report current drain rate) My testing and subsequent numbers are proved accurate by the charge rate over time vs displayed current rate vs battery state. So I believe in this case the numbers reported by Current Widget are quite accurate.
[email protected] said:
USB on samsung 1A charger: 10050mah
Click to expand...
Click to collapse
That would be 10 amps - the battery would charge in no time
The rates are from a dump of a register on the phone and are ten times the ma being used/charged.
accuracy
This makes alot of sense, thank you. In this case the results are still valid as long as we divide the result by 10 at the end of the formula. The recharge rate with MHL is limited to 300ma, which inevitably leads to battery drain. There must be a software switch to override the maximum charge rate.
Charge cable
Use a cord meant for charging or a very short cord. The wire used in a normal usb micro cable is a very fine gage and gives enough voltage drop to severely limit the current. This is even with the high power charger or the shorted data lines
cord length
Thanks for the advice, but I have already tested multiple cables, down to just 2 feet. Voltage drop is negliable in any cable i have tested with. It is obviously a software limiter of some type. With MHL cable plugged in but not active, regardless of the source power, charge rate is limited to 300ma. Test it for yourself!
Read this thread, it's very informative.
http://forum.xda-developers.com/showthread.php?t=1519084
I have a Samsung MHL adapter and when I used it last night, the battery status showed "AC" but it only was drawing 460 ma according to the charging register (which the current widgit uses). With the same wall charger and cord plugged directly into my phone, the charging register starts out at 1007 ma and drops to the high 900's.

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