I'm using a pi in a portable application, where it will be powered by a cellphone backup battery. The battery part works fine, but I'm concerned about the possibility of the system continuing to run as the battery becomes discharged. In most cases this will not happen, but it's not impossible.
To avoid unpredictable operation, I'd like to include a circuit that will detect a low battery condition and drive an IO pin low, which could then be used to start an orderly shutdown procedure. I've searched, but even though this seems like it should be a common issue, I haven't found anything really useful. The circuit needs to be simple, small, and use minimal energy on its own. Any ideas?
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Hi,
I've got a very strange problem: After replacing the display of my Alpine the 2nd time, the display is just light and yellow when the battery is full.
As the battery level gets lower and lower, the problem disappears.
When the battery is 100% full, there is no way to get a screen (except reset). Everything is just white!
The more lower the battery, the more and quicker are the ways to get a screen: When I call the phone, the phenomen disappers or when I switch on wireless lan or bluetooth.
When battery is ca. at 60% level the display works normal. The phenomen is gone.
My obersvation is:
- The lower the battery, the more is the display working
- The more "power consuming" things (incoming call, activating camera, pressing buttons, wireless LAN, ...) I do, the faster I can get a working display.
First, I hope you can understand my observation and my description.
First question: What could this be in your opinion? It is no software problem as the problem persists over hardresets.
My assumption is: Maybe there's a voltage regulator or a capaciator broken. Or something similar. This means that the voltage level is maybe just a little bit higher than normal, say a few mV. For all other components this does not matter. Except the display.
Can this be true?
At the moment, I can work normally with the PDA iff I just load the battery up to 60%. But as you might guess this is no persistent solution.
In my opinion, I could do two things:
1.) Build something that draws exceptional high power for just a very small time and activate this thing when powering on the device. This would not solve the problem but make the PDA useable again. But: How could I do this?
2.) Better way: Repair. Does anybody have some insight of the hardware? Is there a regulator or something that would explain this phenomen? Where is it and how to replace/repair (Soldering SMD would be no problem).
Thank you very much in advance,
Niki
i bought my diamond mainly for the gps built in device...
the problem is that i use it allmost every day + i use a bluetooth handsfree with it...
becouse of the low battery issue it's allways connected to the car charger in the car while im driveing and useing the gps+bluetooh
every day it get so hot that it stop chargeing the phone and i lose power for the rest of the day...
and i replaced 2 screen allready becouse of the heat...( the oily liquid thing)
what can a man really do about it?
there is a way to prevent the heat? or just disable the heat protection from chargeing?
I find my phone heating up during long phone calls. I haven't had a chance to however a common resolution is to update the radio stack. To do this you update the SPL on the phone. Thats what I have read haven't done it yet as I said.
... And I think many people (including me) who have done it didn't find much change...
I have the same issue.
Charging the Diamond on the car and using it at the same time as a navigation system can be a problem. There are mainly 2 components that produce heat (the processor handling TomTom) and the battery.
This is even worse if the Diamond is on a hot environment exposed to direct sunlight (very common on my car ). There are times that the device is so hot that it shuts down completely and it doesent even turn on when it's charging (probably some sort of security temperature sensor that switches off the equipment at high temperatures).
Placing the Diamond on a cool environment seems to work like a charm. On hot days i do not place the diamond on it's standard support, instead i place it very near the air conditioning exit, cooling it continuously, and like that Diamond can be charged and used like a Navigation device at the same time without reaching high temperatures. Performance is very stable.
I believe that charging the battery on hot environments is very dificult (much slower), GPS navigation aplications suck a lot of power from your device and if it is on a hot environment the battery will not be able to handle with charging and delivery of power to the device. On cool environments i have no problems
montanelas said:
I have the same issue.
Charging the Diamond on the car and using it at the same time as a navigation system can be a problem. There are mainly 2 components that produce heat (the processor handling TomTom) and the battery.
This is even worse if the Diamond is on a hot environment exposed to direct sunlight (very common on my car ). There are times that the device is so hot that it shuts down completely and it doesent even turn on when it's charging (probably some sort of security temperature sensor that switches off the equipment at high temperatures).
Placing the Diamond on a cool environment seems to work like a charm. On hot days i do not place the diamond on it's standard support, instead i place it very near the air conditioning exit, cooling it continuously, and like that Diamond can be charged and used like a Navigation device at the same time without reaching high temperatures. Performance is very stable.
I believe that charging the battery on hot environments is very dificult (much slower), GPS navigation aplications suck a lot of power from your device and if it is on a hot environment the battery will not be able to handle with charging and delivery of power to the device. On cool environments i have no problems
Click to expand...
Click to collapse
that's what i do
but...that's exactly the reson you get the oily liquid underneath the screen!
humidity!!
the device get warmer and warmer and the air conditioning is trying to cool it down ( successfully ) but this combo get the humidity
it's a lose lose situation
So the other day, I forgot to close an app down--the Schwartz Unsheathed, if you are curious--and when I fished my phone out again, it was hot. Very, very hot. Battery information indicated 41C which, in the grand scheme of things, isn't that high (wouldn't worry me with a PC's graphic card, for example, or CPU) but it felt incredibly warm to the touch. Fine, I shut the app down, removed the battery cover and let the phone cool down. No problem.
It might be the apps I've been trying since then, but I have been experiencing performance and stability issues. Things slow down sometimes. On the Desire ROM, Rosie kept force-closing every now and again. On Enomther's which as we all know is just about the stablest thing that ever stabled, Launcher2 does ditto (the Launcher Dock may be the culprit, though, as it seems to do some weird **** and I've removed it since. Fiddling around with BetterCut also seems to cause force-closes). So could that be it? Did the phone overheat (but if so, shouldn't it have shut itself down) and now something's broken? Getting antsy. :/
41°C should not be a problem, but consider that this was a measurement from the battery pack and that a sensor like that can easily go +/- 5 to 10 degrees.
so well, some chip on the nexus could have gotten way hotter than 41°C. maybe something fried, some defect that was already there and now its really broken.
still, this can be a bit subjective, the phone will seem broken if you think it's broken you can always do a factory reset, reflash the current rom and try from there.
Yeah, could just be my own jitters--I'd experienced issues before, usually caused by a ROM or whatever--and lately my PC's been having problems, so it might well be some kind of placebo effect. Unless it and my N1 magically entered a symbiosis or something.
Thanks for the quick reply.
once my phone accidently fell onto my bed and under my pillow while i was charging it over night and i woke up at 4 am and found a burning out nexus under my pillow. i unplugged it and nothing seemed damaged but it still worried me.
I think if you are worried about it and you are rooted you should install SetCPU. It has a profile designed so that is you his a preset temp it will down clock your CPU.
I use setCPU to save my batterylife ie.
100% - 50% run full cpu on demand.
Idle/Standby downclock to 400Mhz
50% or less down clock to 600Mhz on demand
20% or less down clock to min.
I also complement this with locale for low bat. dimness, wifi off, bluetooth off. etc.. etc.. ( a little off topic I know)
Well, looks like updating More Icons Widget was what did it; things seem to work okay now.
Was wondering what the maximum advisable temperature is?
Maybe the phone has protection for the CPU? but Li-ion batteries dont like heat, it shortens their effective life.
my battery reached 44.3C yesterday on a 4 hour journey in the car using co-pilot and the phone actually net discharged despite the fact it was on a 1A USB charger for the entire journey - about 80% at start of journey and 20% at end.
I've installed setcpu now and set the temperature profile to drop the max speed to 768 if temp is >44C and another one to drop the speed if power is less than 30%, may need further tweaking though. This was not in my car and the back of the phone was effectively unventilated, in my car I have an open backed holder near an air vent.
For the past couple of weeks, my rooted Nexus 6 (64GB, rooted, unencrypted user partition, carrier Verizon) was running hot for no apparent reason, thus, poor battery performance. I literally cannot figure out what was causing it, and start turning down the application notification down to a minimum. That helped a bit, but does not resolved the issue. I also cannot figure out why I was running out of storage space.
A couple of days ago I noticed that cache usage on storage uses 17GB. After I cleared it, everything seems to run much better. The unit no longer runs hot for no apparent reason, and battery power retention works better. Anyone else experiencing this?
Not with the cache, but one day (only once thank god) my phone overheated and shut off on me. Just had the nexus in my pocket and when I went to look at the time it was almost to hot to touch. I turned it back on after it cooled down and haven't had a problem since. The phone also was having programs crash a lot on me as well right before this happened. My phone is rooted and I did the update to 5.1.1. I haven't had the issue or crashing since. I doubt that's what stopped it from happening again but still.
...
MisterChuffy said:
Once mine did this too I charged and it God really hot. It wasnt able to touch it really. Unfortunately I wasn't able to see the temperature but it has to be something about higher than 60*°C. I turned it after a while and had to wait like 20 minutes then it was normal. I started again and since then no issue.
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Click to collapse
i get mine to 90C all the time, on purpose, and i can hold it fine. 60C+ is easy to hold. and it takes seconds for it to cool down.
My N6 gets very hot occasionally -- almost too hot to handle. I've never had a phone behave this way. In spite of some assurances that it has an auto-shutdown mechanism if it gets dangerously hot, I'm still concerned.
Isn't heat bad for electronic components? I've read that Li-Ion batteries degrade faster when hot.
RealDogBoy said:
My N6 gets very hot occasionally -- almost too hot to handle. I've never had a phone behave this way. In spite of some assurances that it has an auto-shutdown mechanism if it gets dangerously hot, I'm still concerned.
Isn't heat bad for electronic components? I've read that Li-Ion batteries degrade faster when hot.
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Click to collapse
If getting that hot have rogue app or something else locking CPU wide open. I know having Bluetooth enabled with nothing to pair to will cause this. It is your setup and not a regular issue with device.
prdog1 said:
If getting that hot have rogue app or something else locking CPU wide open. I know having Bluetooth enabled with nothing to pair to will cause this. It is your setup and not a regular issue with device.
Click to expand...
Click to collapse
It's not Bluetooth -- I keep that off unless I'm using it. I don't think it's a rogue app either. One incident that I remember: I was updating a lot of apps over wi-fi and charging (Qi wireless) at the same time. My thought was that the Qi charging was generating some of the excess heat (since it's not as efficient as just plugging in the micro-usb) plus the CPU was working hard with the updates.
RealDogBoy said:
It's not Bluetooth -- I keep that off unless I'm using it. I don't think it's a rogue app either. One incident that I remember: I was updating a lot of apps over wi-fi and charging (Qi wireless) at the same time. My thought was that the Qi charging was generating some of the excess heat (since it's not as efficient as just plugging in the micro-usb) plus the CPU was working hard with the updates.
Click to expand...
Click to collapse
Yes QI charging causes heat and will eventually eat your battery. Should never download and QI charge at same time. Looking to execute your device. Lol
So I don't know if anyone else have this problem. I'm running stock Sony Xperia Z rooted, the problem was there before I rooted it too. Whenever I use the phone for semi-heavy tasks like browsing facebook.com or watching youtube videos the battery drains quicker than what's being charged.
Is this normal? Does anyone else have this problem?
As i saw on my friend phone, this is normal on stock and on any fw. IMO battery is just old and that's reason why it's happening.
normal on stock, it's batter to install CM 12.1
Does CM 12.1 fix this issue???!!!!because this issue eating my head since a long time..i m using stock rom
For problem of draining battery when charing and using phone at the same time: its normal, and not only for Stock rom, its actually problem of how phone distribute power and how demanding those apps are that you use. An because most of apps, even those well known like chrome or facebook lack any optimization and android it self really can manage that either... we end in thin phones with powerful hardware(because xz is still good in this term) that make loots of heat and need lots of power.
Solution that I found when I used XZ was buying charger that had 2A or 2,4A instead of deafult 1.5-1.8A. Its not good for battery lifespan in long term time, and it make phone a bit more hot than normally, but Its only solution that actually work: phone dont lose charge when using apps and it charge way faster than normally.
In terms of hot phone when using heavy apps(because even facebook is heavy looking how resource demanding it is)... its normal, Its really bad for usage experience, its annoying... but its normal, new phones have the same problem, OnePlus, Xperia Z3... they all the same. And its all because of power that Android need to run smooth, and thickness of devices.
In Xperia Z we have glass front and back, and glass is not that great in terms of thermal conductivity, so it can keep that temp for few minutes after usage, and it can get hot really quickly. But even if now I put wooden custom made back on my xz, and I put on chip thermal paste that I had after replacing CPU in my pc, it dont get so hot, but I use it now as a smart extension device for my TV, and with MHL cable+charging it hot all the time, but after whole month of usage as a smartTV I can say that high temp dont affect performance so beside annoying usage its not that bad.
the phone lowers charging current when it's getting too hot, i noticed it with amperly app. also thermanager.xml has listed these values in system/etc/
yes this phone is terribly designed, charging takes forever even if you are not using it