Hello! I am working on building an android phone (got a cheap Blu Dash Music C) solar powered server. I am working on the power system and an torn between several possible power options, and I guess it boils down to the following scenario:
What will happen if I root the phone and modify the "fast charge current" to 2000ma (or whatever the max rate the hardware allows) but the source is unable to supply that current? Will it just charge at whatever the available power rate is, or will this cause some issues which I have not thought of? I am thinking I will replace the phone's battery with a 20ah 3.7v (4p 5ah). If it would indeed be capable of charging at 2a, this would be perfect as:
- I could use all parts I have on hand, and use the phone itself as a charge controller.
- That would be similar my solar panels output (wattage)
- If power gets low, phone should power off like normal vs having to install some type of low voltage cutoff for an extrnal system.
But obviously as it gets dark power will drop off to zero.
Thoughts?
Thanks
P.S. Got this working reat with a Raspberry Pi and simple SLA battery but I believe an adroid phone will use less power overall and has 3G/4G built in.
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Hi guys,
I've been trying to use the navigation on my SGS2 (particularly iGo). The problem is that, even the phone is connected to the lighter socket, and indicates that it's charging, the battery level still drops. I tried two separate USB power adapters, one rated at 1000mAh and another rated at 2000mAh, same results. The phone was in front of the air vents in the car, so no question of overheating.
Any ideas what may be happening?
Do you know what are the power requirements when nav/data are running?
Thank you
I noticed the same, back on my former galaxy I7500, and still on my sg2.
Navigation works great, but use simultaneously 3D display, gps and wifi for localisation, sensors for direction and position intropolation (I guess), plus 3g.
It seems that heavy use comsume more juice than the typical 500ma you get out of a car plug.
On SG2, it drain slower than on the I7500, despite the larger screen. I guess the hardware is more energy efficient.
If it's a real issue, you can try to :
reduce screen brigthness
switch from 3g to edge only (fast enought for navigation)
Disable bluetooth (unless you use blutooth to get navigation from car speakers).
Use a 1000ma usb car plug
The cigarette plug on my car is supposed to give out some 10Amps, so there is juice available. In any case, I'll try different adapter/cable/car combinations, see if all behave the same or it's just a case of incompatibility.
I am using bluetooth to connect to the car audio system, so that has to stay. I suppose I can disable data connection as the maps are on SD, but not sure if it would make a difference. Anyway, is there an official (or unofficial) spec about the max current drawn by the device?
Read in some other thread that charging is limited to 700 mA so don't think it will matter.
So no workaround?
Can you please point me to that thread?
No way to fix this yet. Charging is limited to 650 mA in the driver, and the phone pulls more than that doubt tasks like navigation or gaming. Your best shot is use min screen brightness to bring current draw down.
It seems part of the problem was the USB cable, it was a 3rd party one. I tried now with the original cable, and the battery level remained constant, which is a definite improvement
Will try with the second charger (the 2000mAh one) and see what gives.
The stock charger from Samsung was for 0.7Amps and it charges ok, but I find it slow.. about ~4 hours to fully change my SGS2 from with less than 10% left of battery life.
If I plug into the laptop, it takes like ~6 hours due to the slow trickle charge with 0.5Amps.
I don't know what the max pull is allowed on this phone, but I did find that when I charge with a 1Amps charger, I can get it from less than 10% to full in about ~3hours.
So, I tried a few such charges and have noticed some strangeness.. (all with the same test conditions, start charging with less than 10% and with the stock usb cable for the phone)
1) older Belink ac-usb 1Amps out put, it does seem to charge the phone good and faster finishing around ~3 hours ... but, when charging, the touch sensitivity of the screen is out of whack, any subtle movement, will cause the screen to jump around.. like in gallery, trying to select an individual pic is difficult as the screen jumps around; forget about using the browser and selecting links...not sure why..
2) HTC thunderbolt charger 1Amps output (http://www.amazon.com/gp/product/B003WM6SOU).. same issue here, charges faster, but makes the screen jump around
3) iPhone charger 1Amps output; this seems to work the best for me so far.. charges faster ~3hours and while charging the screen behaves normally, I am able to use gallery and browser fine...
4) iPad 2 charger 5.1 V and 2.1Amps: Still charges the phone ~3 hours, but same side effect...
Anyone else have the screen sensitivity issue and what chargers are you using?
I haven't seen any issue when I used a HP TouchPad Charger rated at 2.0A I think..
Max pull is 650 mA - this is set by the charger chip itself.
If the phone thinks you have a normal USB connection to PC instead of a dumb charger, it will be 400 mA.
Having a charger rated more than this won't hurt, but it won't help.
Monoprice "1A" car chargers are rated 300-400 mA at best - the ONLY monoprice product I've ever been unhappy with in my life.
In general, you want to make sure USB D+ and D- are shorted together by the charger - this guarantees that the phone sees the charger as "dumb" and goes to 650. Exception are media and car docks - whatever you connect to these will be assumed by the phone to be a high current "dumb charger".
All phone power usage (CPU, screen, etc.) counts against this current budget - e.g. if you have 200 mA of load, only 450 will be going into the battery.
Unlike the I9100, we don't appear to have any way to change these charging currents. Our phone, for whatever reason, has an additional chip for charge control (MAX8922) instead of using the charge control built into the main power management chip (MAX8997). This is disappointing, I was really hoping to bring over the "charginghacks" modifications from my Infuse kernel series.
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.
Click to expand...
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
I want to make a bike charger for my S3. I made sure the converter is working and can deliver more than 2A of constant current at 5V.
As long as the phone does not detect the converter as a proper charger, it won't draw more than 500mA which is not enough to maintain charge while navigating or using apps. I have tried to measure out the charger that came with the phone and found out that the data lines are shorted. Apart from this, there seems to be no connection from the data lines to the supply voltage. I tried to replicate this on my selfmade charger but still the phone won't draw more than 500mA. I tried searching the net for info on the charging circuit but can't seem to get anywhere. I would like avoid cracking open the original charger.
Does anyone here have an idea what has to be done so the phone will draw more current from a homemade charging device?
you can always get a Kernel with charging control and up the amperage, but that's more of a workaround
There's a reason why i don't like workarounds like this. It violates usb specifications and may lead to damage to a regular usb port if handled improperly. It may be possible that i am missing something. Maybe i'll get another original charger and dig deeper into this matter. I'll post results as soon as available
Noume said:
I want to make a bike charger for my S3. I made sure the converter is working and can deliver more than 2A of constant current at 5V.
As long as the phone does not detect the converter as a proper charger, it won't draw more than 500mA which is not enough to maintain charge while navigating or using apps. I have tried to measure out the charger that came with the phone and found out that the data lines are shorted. Apart from this, there seems to be no connection from the data lines to the supply voltage. I tried to replicate this on my selfmade charger but still the phone won't draw more than 500mA. I tried searching the net for info on the charging circuit but can't seem to get anywhere. I would like avoid cracking open the original charger.
Does anyone here have an idea what has to be done so the phone will draw more current from a homemade charging device?
Click to expand...
Click to collapse
The key in shorting out the data lines to achieve FAST charge rate is that the Phone sees it as shorted at the Micro Usb connection point of the phone. Anywhere else down the line is irrelevant. Depending on the Kernel, most phones slow down the charging rate after...hmmm...anywhere between 70-100%. The closer to full charge...the slower the charge rate gets...until it becomes a trickle charge...just in case you don't know.
If your still having issues, please post back with a more detailed explanation of your wiring and parts as best as you can and I will help you with it.:good:
[Solved] Charger for S3
Considering your suggestions i was asking myself if i've done everything right and as it turned out, i hadn't.
I do know that chargers current depends largely on the charging state of the battery. Good chargers start initiate completely drained batteries with a low current, which is ramped up to the max at around 5-10%. After reaching 85-90% the current drops down to small trickle pulses as the charging finishes. These values can be adjusted within the firmware/kernel to get a longer battery life/more power. That's why i always do charging tests with a battery that is at least down to 33%.
But back to topic now
Using an oscilloscope i found my switching regulator to have about 150mV ripple voltage which apparently is a bit more than the S3 is willing to take. After sorting it out, ie. resoldering a cold joint, it finally works as expected, the ripple voltage is now around 32mV. The regulator could deliver more than 2A before, but only with about 600mV ripple, which i unfortunately overlooked
Charging the phone's completely drained battery, i get around 320-340mA current draw from the battery(12Vnom LiFePO4) .
The phone takes around 950mA at 5.1V. I wonder why earlier charging circuits had to be so "complicated" like with Apple phones or Galaxy Tab, while most newer phones are happy with just shorted data lines.
The circuit i use is composed of a three-phase voltage doubling rectifier, that takes bike from a generator hub in the front wheel. This one is connected to a battery for storage and buffering. A small switching regulator provides 6V 600mA for the lighting system. A larger LM2596-based regulator (you can get those modules around $1.50) provides power for my S3 and a microcontroller that will later be used for monitoring the systems voltages and rotational speed of the front wheel. EAGLE layout files for circuit and PCB will be finished soon.
tl;dr: Is there a confirmed kernel on 6.0.1 that actually allows for a 2Ah charge, am I missing something obvious or am I just SoL?
I recently picked up a 32gb N9 from a sweet deal on swappa. As soon as I got it, I unlocked bootloader before first boot, loaded up the system 6.0.1 image and went to town with SuperSU and ElementalX kernel. I never ran the tablet during the Lollipop era, so I missed out on all of the fun reports of slow performance and constant redraws as performance for me has been pretty good on Marshmallow (not as great as a 6P, mind you, but not many devices are that great).
I say all of this to ask this: ElementalX (as well as a number of other custom kernels) say they have unlocked the ability for the tablet to charge at 2Ah. While I DO have a toggle for a "USB fast charge" in my kernel tweakers set to ON, the tablet doesn't actually seem to charge at that rate.
I used the app Ampere to check how many amps were coming through to the N9. I used an old school ipad 1 power brick (which can charge at 2.1A) with a USB micro cable, and the highest it reported charging was 1.4A, which I think is basically right under what the N9 is supposed to charge at normally. According to google support page for the default charger, "The input voltage range between the wall outlet and this charging unit is AC 100V–240V, and the charging unit’s output voltage is DC 5V, 1.5A." Also, a standard USB port on my desktop computer will charge at 400 mA (or .4A), which is right under the standard 500mA, even with the setting turned on. There is no fast charging going on here in both cases.
So, this leads me to believe that Marshmallow (or something else) is stopping the ability to charge at those rates. Again, I've never used Lollipop on my N9, so I have no way of knowing whether or not kernel's USED to work before and simply no longer do... It's either that, or my power bricks aren't actually charging at the correct rate, but I'm led to believe its the kernel/tablet ensuring the charge doesn't go over the default rate.
I have been told that one possible reason for this happening is that the N9 has inherent idle power drain? Actual amperage will report around 1.7amps as a result. However, I don't know if this is actually the case because I've never gotten that much charge on my charger.
I'm not sure about 6.0.1, but NaHCO₃ and Elementalx threw off all the charge measuring apps I installed. Although, using my s4's 2 amp chrager gave a significant increase in the speed of charging over my stock charger.(I have reason to believe that my stock charger is broken but this does't affect my first observation)
If your battery is charging from empty to 100% in 3 hrs, you are getting the max charging speed. That's what I was getting on LP with a 2A wall charger.
I see you've already tried SimpleStream kernel, which claims 2A charging, so you're not likely to get higher charging rates than that.