Related
Hi,
I rooted my N1 and installed a flashlight app (N1 Torch) that uses the phone's LED flash. It warns you that continuously using the flash might break it, though.
What has been your experience? Does "continuous use" mean "hours", "minutes" or just "more than the 0.5 seconds the flash is supposed to turn on when you make a photo"?
frandavid100 said:
Hi,
I rooted my N1 and installed a flashlight app (N1 Torch) that uses the phone's LED flash. It warns you that continuously using the flash might break it, though.
What has been your experience? Does "continuous use" mean "hours", "minutes" or just "more than the 0.5 seconds the flash is supposed to turn on when you make a photo"?
Click to expand...
Click to collapse
I think that using it for a couple of minutes would be fine, the problem is that if it gets too hot it could damage the the phone especially the camera. I remember that I installed a similar program on my nokia n70 and several times happened that by accident i turned on the led while the phone was in my pocket, I only noticed that when i started to feel something burning in my pocket Now my n70's led and camera doesn't work anymore... so just be carefull not to turn on the led by accident
I had read that the LED flash was designed for quick bursts. If that is true than constantly running it could - at least - burn out the LED bulb. I doubt is it user replacable, so that is not a good thing.
I have hoped to use Torch too, but have decided its just not worth it. I will just use the lit up screen as a flashlight.
Yeah.. I'm thinking about uninstalling torch I get random clicking after I turn the app off
It's an LED.. by default LEDs are low-power, have low-heat emission and super long lifetimes. They also tolerate turning on/off repeatedly for extended periods of time.
I somehow doubt you could do any damage to the phone/LED.
Has anyone even heard of doing damage this way, or is this just speculation and ass-covering in case something goes wrong?
my old sony erricson w810i LED flash lasted for atleast an hour of continuous use with no ill effect.
LEDs don't get that bright either, not the ones you are thinking of. The LED in the nexus one is much brighter than "usual", and it's also much smaller.
High power LEDs (HPLED) can be driven at currents from hundreds of mA to more than an ampere, compared with the tens of mA for other LEDs. They produce up to over a thousand lumens. Since overheating is destructive, the HPLEDs must be mounted on a heat sink to allow for heat dissipation. If the heat from a HPLED is not removed, the device will burn out in seconds.
Click to expand...
Click to collapse
(bold for emphasis)
http://en.wikipedia.org/wiki/Led#High_power_LEDs
Obviously the LED in the N1 is designed to deal with its heat under "normal usage" for a camera flash, and it probably can handle longer usages than the stock camera, but I wouldn't push it too far.
Edit:
If anyone wants to use some debug tools to find how many mA the phone pulls when the flash is on vs when its off, they could probably look up the usual heat generation for an LED of that size and see how 'safe' it is to run.
I just contacted the developer on google wave, waiting for his reply now. Please give me your address if you want to be added to the wave.
DarkLord7854 said:
It's an LED.. by default LEDs are low-power, have low-heat emission and super long lifetimes. They also tolerate turning on/off repeatedly for extended periods of time.
I somehow doubt you could do any damage to the phone/LED.
Click to expand...
Click to collapse
High power LEDs do get hot (i have an LED flashlight that gets quite hot after prolonged useage. it chews up batteries as well) and, ill bet that continued useage at high output can damage it.. and the camera... theres a reason that its not enabled stock
A way around heat and power is the cycle the LED at 30-60hz. I am unsure if the developer of N1 Torch could make it happen with software alone though.
Not sure if this helps but I have shot several videos and even changed a flat tire with my BB Storm LED. Besides draining battery, the only thing I worried about was space on mr MicoSd because I could only leave it on continuously in video mode.
I used mine this morning for about 5 mins and no problems.
Still works and so does the camera.
Wait, so the Nexus One uses the High Power LED, not a regular LED?
NexusDro said:
Wait, so the Nexus One uses the High Power LED, not a regular LED?
Click to expand...
Click to collapse
no he was just using that quote to prove that some leds do produce heat. judging by the brightness i would say its relatively high power, and because htc might not have mounted the led on a heatsink big enough to keep it cool after prolonged use because they designed it for a camera flash, not a flashlight. so better safe than sorry.
britoso said:
my old sony erricson w810i LED flash lasted for atleast an hour of continuous use with no ill effect.
Click to expand...
Click to collapse
Ya! I had a K750 (flashed with the W800i firmware) that had as one of it's features, used the flash as a torch and a SOS beacon.
SonyEricsson's XPERIA X1 (Win Mo device, HTC manufactured) has an app for the flash too. The app has two options.
First (dimmer) is mostly OK (not recommended for hours of use either).
Second (brighter) caused a meltdown of the LED's plastic holder if used for long enough. The holder melted over the vibrator motor, thus shutting it stiff and ruining it.
aad4321 said:
exactly. led's dont get hot.... someone should email the developer of the app. i know he has done some extensive testing. post what you get
Click to expand...
Click to collapse
Folks should stick to things they know. There are many VERY high power LEDs, such as those used as a flash. Depending on the application they end design may be to be used in short bursts because they create so much heat. LEDs waste LESS power through heat dispersion than a conventional lamp, but they do indeed create heat. I've seen LEDs that need a heatsink 10x their size to keep them cool. In the interest of size I would be willing to bet there is not enough heatsink on the LED flash to be able to use it for extended periods of time without burning it out.
comparing light sources from different phones as others have done here is silly. Unless you are positive that they are the same LEDs and that they have proper cooling behind them, then don't compare.
Source - Me. almost 20 years in the semiconductor design and test industry
Seconded. It's possible the LED is being driven at peak currents, or beyond too, which is fine for a short burst but not for prolonged use.
I'm the developer of N1 Torch, and was pointed towards this thread. So I can offer some answers and insight...
Standard brightness is supported 'naturally' by the LED kernel driver. I tell it to come on, and it comes on until I give it a command to turn off.
High brightness is only enabled by the kernel for ~0.5 seconds before the kernel turns it off automatically. I simply send the command repeatedly to keep it on.
I had the app tested on a sacrificial N1, and the following were the results:
- On standard brightness mode, the torch ran for over 1/2hr continuously with no problems or heat issues detected.
- On high brightness mode, the torch was noticeably warm after 1/2hr, and there was a bit of a 'heat' smell coming from it. After a further 18 minutes (total 48 minutes) the LED started flickering of its own accord and was hot. After cooling, it resumed working normally (no idea how the lifetime was affected).
You can use your own judgement based on these results (and of course, YMMV due to manufacturing differences). I would be happy to say that standard brightness is fine for extended use (1/2hr at least), but try to limit high brightness to a few minutes at a time.
Will using a torch app kill the longevity of the LED light?? I thought I heard this before somewhere but I'm wanting to install the Nexus Torch app on my N1..
pookguy88 said:
Will using a torch app kill the longevity of the LED light?? I thought I heard this before somewhere but I'm wanting to install the Nexus Torch app on my N1..
Click to expand...
Click to collapse
search is your friend...
http://forum.xda-developers.com/showthread.php?t=624592&highlight=torch+app+led
@Krumb
Thanks for the link.
But the discussion stopped in April, pre-froyo.
Now that G has enabled Led-on Video recording in Froyo, I am curious to know if any one faced issues while using it for prolonged night time video recording.
I personally used it for a max of 5 minutes continuously, for video recording as well as for use as torch, faced no issues.
I think the light is fine with 'normal' brightness for extended use, but not the ultra-bright setting.
LED light has "lifetime" - which is, it's built to last X hours on average.
Each time you turn it on, you take Y seconds out of its lifetime.
By analogy, each day you live, you're 1 day closer to death. You don't stop living to avoid death, do you?
Yes, the LED will die one day if you use it. If you're not unlucky, it'll be way after your phone turned to a piece of junk. If you're unlucky - it can die the next time you turn it on. Pure statistics of semiconductors, can't predict it.
Has anyone solved the "Low battery" and "immediate turn off" problem yet?
Man this is the most frustrating issue EVER.
I'm running SRF 1.1.0
I have a 3500 mAh battery.
For some Farking reason, if the battery is under 50% and I get a call. It will RANDOMLY beep LOW BATTERY and turn off, in the middle of the farking call!!!
You turn it back on and it'll have 40+ % charge left!!!
AHHHHH!!!!!
After watching the 25 how to videos, I fixed almost everything that pissed me off, but this one thing drives me bonkers!!!!
I think that's the battery. Is its a yoo-bao from china (cheapie) or a good brand from a reputable source(sedio)? I have that problem with all the cheapies I bought on ebay.
Sent from my SPH-D700 using XDA App
It's not just the battery. My stock phone and rom does it too when the battery gets to 15%. When it reboots it has 20 or 30%.
This phone should never have been released with such a serious bug.
Sent from my SPH-D700 using XDA App
For "such a serious bug" it doesn't seem like many of us have it... I can keep a call all the way to 0%...did it a few minutes ago. Have you tried calibrating the battery stats?
Sent from my SPH-D700 using XDA Premium App
Now I dont normally let my phone get down to 0% but yeah i know i've gone WAYYYYYYY past even 10% and the phone hasn't done this. Stock battery not extended.
Kcarpenter said:
For "such a serious bug" it doesn't seem like many of us have it... I can keep a call all the way to 0%...did it a few minutes ago. Have you tried calibrating the battery stats?
Sent from my SPH-D700 using XDA Premium App
Click to expand...
Click to collapse
it's a cheapy battery.
However, it's also a bug somewhere in some software...
If it hits 15% when u are NOT on a call, the phone doesn't shut off. It's only when you're actually talking that it does it.
I'm surprised to hear STOCK people saying it happens to them... When I had my phone stock it didn't do this. I assumed it was a ROM issue.
I would try calibrating... I believe there's an actual app in the market to do everything for you. I'm fairly certain its free, so ill post a link, but if its not, I apologize, and well get a mod to take it out.
http://db.tt/NaGV1TB
J3ff said:
I assumed it was a ROM issue.
Click to expand...
Click to collapse
I love how people assume I sprinkle magic fail dust on my ROMs.
Charge to 100% with the device off and wipe battery stats in CWM.
Key word there, "Assumed"
Kcarpenter said:
For "such a serious bug" it doesn't seem like many of us have it... I can keep a call all the way to 0%...did it a few minutes ago. Have you tried calibrating the battery stats?
Sent from my SPH-D700 using XDA Premium App
Click to expand...
Click to collapse
Yes. I've calibrated my battery. I have seen a couple threads on the issue. I have repeated the issue on several roms and modems. Happens every time i'm on a call and the battery gets to 15%. That makes it serious since it is a phone after all. What if I was talking to 911?
Sent from my SPH-D700 using XDA App
k0nane said:
I love how people assume I sprinkle magic fail dust on my ROMs.
Charge to 100% with the device off and wipe battery stats in CWM.
Click to expand...
Click to collapse
Not just YOUR rom, I've read that this is a problem on all different ROM's including the stock one!
J3ff said:
Not just YOUR rom, I've read that this is a problem on all different ROM's including the stock one!
Click to expand...
Click to collapse
Right, but you said you assumed it was a ROM issue before you found out stock users had it.
k0nane said:
Right, but you said you assumed it was a ROM issue before you found out stock users had it.
Click to expand...
Click to collapse
well even stock is a rom right?
What I'm hoping for is I can figure out what you guys are running that doesn't crash on you when the low battery beep happens.
I think this is a battery issue. I never had this problem with stock battery and it happened twice on cheap 3000 ma battery I bought. Returned the battery and got another one (same kind) and this one works fine. I think this is a manufacturing problem with cheap batteries. When you look at reviews of more expensive ones online, you never see anything about this problem.
I have found the solution! It turns out that our phones, much like a simple light bulb, just don't function when they don't have enough juice...
Since I can't modify a light bulb to magically require less power, the only solution I have found is to provide the specified power level. I have applied this same method to my phone - when the battery gets close to that magic threshold, all I do is - get ready for this - charge the phone again!
Seriously, though - everything takes power to operate, and a low battery can't put out the same current and voltage as a fully- or even half-charged battery. This isn't a bug, it's just a fact of life (with current technology, anyway). Who here complains when their almost-dead AA batteries can't power an Xbox 360 controller? Most of us just replace them with fresh ones (or charge them) and keep going.
Sent from my SPH-D700 using XDA App
styles420 said:
I have found the solution! It turns out that our phones, much like a simple light bulb, just don't function when they don't have enough juice...
Since I can't modify a light bulb to magically require less power, the only solution I have found is to provide the specified power level. I have applied this same method to my phone - when the battery gets close to that magic threshold, all I do is - get ready for this - charge the phone again!
Seriously, though - everything takes power to operate, and a low battery can't put out the same current and voltage as a fully- or even half-charged battery. This isn't a bug, it's just a fact of life (with current technology, anyway). Who here complains when their almost-dead AA batteries can't power an Xbox 360 controller? Most of us just replace them with fresh ones (or charge them) and keep going.
Sent from my SPH-D700 using XDA App
Click to expand...
Click to collapse
This! Cheap batteries are never worth the money. I bought some cheap chinese rechargeable packs for my 360 controllers... they ALWAYS show low charge even if I just charged to full. Same deal with cheap chinese cell phone batteries.
I am sure the battery calibration is way off with one of the cheapies.
styles420 said:
I have found the solution! It turns out that our phones, much like a simple light bulb, just don't function when they don't have enough juice...
Since I can't modify a light bulb to magically require less power, the only solution I have found is to provide the specified power level. I have applied this same method to my phone - when the battery gets close to that magic threshold, all I do is - get ready for this - charge the phone again!
Seriously, though - everything takes power to operate, and a low battery can't put out the same current and voltage as a fully- or even half-charged battery. This isn't a bug, it's just a fact of life (with current technology, anyway). Who here complains when their almost-dead AA batteries can't power an Xbox 360 controller? Most of us just replace them with fresh ones (or charge them) and keep going.
Sent from my SPH-D700 using XDA App
Click to expand...
Click to collapse
Ok Mr. Smarty pants. You are not understanding the problem. It happens with the stock battery too.
The SECOND you hit 15% while on the phone and get the battery low warning, the phone turns off, MID CALL. You turn the phone back on and it will last hours, even on the stock battery.
If it hits 15% without being on a call, it does not shut down.
That is the real problem here.
This has happened to me once , what could be the cause ? Defective phone or software?
J3ff said:
Ok Mr. Smarty pants. You are not understanding the problem. It happens with the stock battery too.
The SECOND you hit 15% while on the phone and get the battery low warning, the phone turns off, MID CALL.
If it hits 15% without being on a call, it does not shut down.
That is the real problem here.
Click to expand...
Click to collapse
You mean just like a 360 controller can have enough juice to turn on, but not enough to actually play? Or how a flashlight will be too dim to be worth it when the batteries get low?
Would it be better if the battery ran like a champ right up to the second that it shuts off without warning? That would fix your problem - no notification when the battery is low (the sudden shut off can't be avoided until we find an unlimited energy source small enough to fit in our phones)
Your expectations are unrealistic. Just sayin'...
Sent from my SPH-D700 using XDA App
J3ff, it's likely the cheap battery. Here's why:
Charge level is a simple linear voltage function. Our phones consider 4.2V to be full charge (100%), and empty to be around 3.6V (0%). The voltage drops roughly linearly between these two values as charge is consumed.
The kicker is this: The voltage seen at the battery terminals is also affected by the interaction between the internal resistance of the battery and the instantaneous load, or current draw. For electronics buffs, this is the classic V=IR, and what happens is that the voltage on the battery will drop by IR in addition to it's unloaded voltage level due to whatever the stored charge state is.
Good quality batteries have a very low internal resistance, and will not drop much voltage due to an increased load. Crappy batteries are just the opposite, and even though they do carry the charge storage (most of the time) advertised, they are only suitable for low load applications.
What's happening is you have a battery with a horribly high internal R. When you make a phone call, the load increases A LOT -- transmit power goes way up. This if why phones get hot when talking on them -- they really suck the juice.
As a consequence, because of the high resistance, voltage from the battery takes a nosedive. At an "idle" reading of 50% (3.9V, thereabouts) you're probably dropping more than 0.3V when the load goes up during a call, the phone panics, and shuts down to protect the battery (LiIon doesn't like to be discharged below 3.3V, and can be damaged).
When you reboot, the high load is gone, so the voltage shows higher again, reflecting the fact that there is truly still plenty of charge stored and available. The battery simply can't handle gulps, but only slow sipping.
High internal R is one of the most common reject reasons from mfgs, and those batts are sold on the cheap to dealers and distributors in a secondary market. Honest ones then resell into appropriate application spaces where low-current is all that is needed. Most, however, are not that scrupulous, and sell right back to the same market, leaving behind puzzled and unhappy customers.
Sent from my mind using telepathitalk
On every rom I have used, when I'm outside in a pitch black situation and I need my flashlight on my phone. When I leave it on for more than 60 seconds, the phone automatically restarts. I suppose because the LED gets too hot? This is on Torch bright widget or widgetsoid flashlight using method 2 for led. However I'm fairly sure that using heart rate monitor app in the market the phone can stay on with the flashlight for more than 60 seconds. I'm going to test this now. This is weird since my HTC HD2 could leave the led flashlight on for hours if I wanted. Well I never had it on for more than say 20 minutes but it worked and the phone never restarted. Any help would be great, thanks!
By the way this happens on all roms including with all kernels and all radios.
I wouldn't leave it on for more than 10 seconds at a time. That is just plain stupid.
Damn I hate useless replies!
Sent from my MB860 using XDA Premium App
Ok try this out. You're going to burn out your LED and the reason it restarts is from the heat. When you take a pic in your camera app does the LED flash for 60 seconds? um no.... you need a flashlight? Get those small LED keychain ones.. how's that for useful? Use your head....
And tour HD2 does not have a Tegra 2 in it so perhaps why that one does not overheat. Either way you'll kill the LED. They aren't designed to be used like that.
I have the exact same problem on CM7 - was fine on my HD2 for a very long time too
At times I find myself needing a flashlight for a minute or 2 at times. The HD2's LED never overheated unless you left in death ray mode but I'm not sure since I can't remember ever having a problem ever. Just use regular brightness at a reduced continuous voltage therefore reducing heat production. That's not stupid to need my f*ing phone as a flashlight for a couple minutes when needed. LED's are very efficient and can take a hell of a beating, however they're efficient in nature so leaving it on may reduce it's life sure. But has anyone reported their cell phone led light going out? I have never heard of it so stop posting stupid idiotic comments. Posting dumb offensive comments makes you look stupid. You could respond with an intelligent response unleashing to the world your hidden genius. Instead you decide to do what you do best.
If anyone who may be having the same problem. I have found a solution to the problem. Downloading instant heart rate monitor will allow the light to stay on forever with no problems.
Later
Atrix_E said:
And tour HD2 does not have a Tegra 2 in it so perhaps why that one does not overheat. Either way you'll kill the LED. They aren't designed to be used like that.
Click to expand...
Click to collapse
I'm sorry. I do understand you stating they aren't designed to do that. However I don't care what you think about cell phone led's. I asked a question therefore I would expect an answer. Not an electronic's lecture.
1chris89 said:
I'm sorry. I do understand you stating they aren't designed to do that. However I don't care what you think about cell phone led's. I asked a question therefore I would expect an answer. Not an electronic's lecture.
Click to expand...
Click to collapse
That was my answer. Sorry that you do not like it. Why not troll on now about video playback on your HD2?
Had the same problem with widgetsoid.
Download Tiny Flashlight + LED from the marketplace. My 60 second reboot problem does not happen with this particular application. I am on stock at&t rom rooted.
Sent from my MB860 using XDA App
Atrix_E said:
That was my answer. Sorry that you do not like it. Why not troll on now about video playback on your HD2?
Click to expand...
Click to collapse
Well my suggestion is to you. Next time you post a comment. Please take a moment to think about the question. So then you can give a helpful answer. Questions are meant to be answered, nothing more and nothing less.
jmaddr said:
Had the same problem with widgetsoid.
Download Tiny Flashlight + LED from the marketplace. My 60 second reboot problem does not happen with this particular application. I am on stock at&t rom rooted.
Sent from my MB860 using XDA App
Click to expand...
Click to collapse
Thanks buddy! I will give that app a shot. As for the moment. Instant heart rate monitor from the market works wonderfully.
1chris89 said:
Well my suggestion is to you. Next time you post a comment. Please take a moment to think about the question. So then you can give a helpful answer. Questions are meant to be answered, nothing more and nothing less.
Click to expand...
Click to collapse
Noted and thought about. Wouldn't change my answer.
First of all you don't have to be a flamer, second....you have no clue what your talking about. The led light is led ...led lights put out insanely low amounts of heat...which is why that technology has been incorporated into growing plants...not that it's good ti leave the led on for too long but I have uses the led flashlight for about 30 minutes before on my ATRIX, ya it gets a little warm but that's it. Yes it's possible to burn it out over time but you will be fine for short durations. Why do you think there are so many flashlight apps, if they really caused that much damage google would remove those apps from the market.
And im not talking out if my ass because I know quite a bit on the topic of led technology.
The possible reason for your phone rebooting is because a lot of the flashlight apps out there aren't compatable with the ATRIX for some reason, don't ask me why. You need to download "droidlight" from the market because it was developed for Motorola phones by Motorola ...then I doubt you will be rebooting
But please don't talk like your an expert on the subject and give false information to people because it just adds to confusion for those that don't know. Im no expert on everything so I don't chime in on things I don't know about. Cheers
Sent from my MB860 using XDA Premium App
Atrix_E said:
That was my answer. Sorry that you do not like it. Why not troll on now about video playback on your HD2?
Click to expand...
Click to collapse
Also you should be suspended by mr.clown for a comment like that.
Sent from my MB860 using XDA Premium App
Tiny flashlight +led works great. Has a good widget as well. Don't recall having a timeout. Accidentally turned it on and fell asleep for hour. Woke up to a dead battery and a brown spot on the coffee table lol. Led was still kicking an hour later. I use mine all the time.
Sent from my MB860 using xda premium
Its more than likely the app, I have the same problem using Tesla led + widget locker + cm7. Disregard about damaging your LEDs, as long as the proper voltage is applied... they will never burn out... if its getting HOT(not warm) then I would be worried. LED lights do have a "lifespan" but generally exceed it, tremendously.
Sent from my MB860 using XDA Premium App
J-Roc said:
First of all you don't have to be a flamer, second....you have no clue what your talking about. The led light is led ...led lights put out insanely low amounts of heat...which is why that technology has been incorporated into growing plants...not that it's good ti leave the led on for too long but I have uses the led flashlight for about 30 minutes before on my ATRIX, ya it gets a little warm but that's it. Yes it's possible to burn it out over time but you will be fine for short durations. Why do you think there are so many flashlight apps, if they really caused that much damage google would remove those apps from the market.
And im not talking out if my ass because I know quite a bit on the topic of led technology.
The possible reason for your phone rebooting is because a lot of the flashlight apps out there aren't compatable with the ATRIX for some reason, don't ask me why. You need to download "droidlight" from the market because it was developed for Motorola phones by Motorola ...then I doubt you will be rebooting
But please don't talk like your an expert on the subject and give false information to people because it just adds to confusion for those that don't know. Im no expert on everything so I don't chime in on things I don't know about. Cheers
Sent from my MB860 using XDA Premium App
Click to expand...
Click to collapse
I mean I don't really know anything about it, but if my LED light is on (for a flashlight) it get's noticeably hot within like 10 seconds...
I haven't quite had the same problem as the OP, but I was using TeslaLED with Widgetsoid (had a flashlight toggle in my rotary slider). I turned the screen on, and without unlocking used the flashlight like normal a few days ago, and had it on for 10+ seconds (after 10, my screen timed out like normal). I went to turn the screen on again though, and my entire phone froze - with the LED still on! I had to remove the battery...
I dunno all the technicalities of the LED, nor do I know if this was a freak accident and won't happen again (hopefully!). Might be a problem with TeslaLED/Widgetsoid, or maybe the screen shouldn't go off when the LED is on?
EDIT: Weird, I just tried it out again for fun, and it did in fact freeze my phone again lol. It did the exact same thing: turn on screen, turn on flashlight, use for like 10 seconds. Screen times out, flashlight flickers. Turn screen on, looks normal, but try to turn flashlight off, feel slight haptic feedback then froze.
Being an electrician by trade, I also specialize in luminaire devices, and tend to push LED devices over traditional flourescent, incandescent, halogen & HPS/MH lamps, for various reasons & applications. In fact LEDs last longer than the auxiliary components driving them .. which is why the still have a rated life span, many suppliers guarantee 12,000+ hours.
Sent from my MB860 using XDA Premium App
JaronBang said:
Its more than likely the app, I have the same problem using Tesla led + widget locker + cm7. Disregard about damaging your LEDs, as long as the proper voltage is applied... they will never burn out... if its getting HOT(not warm) then I would be worried. LED lights do have a "lifespan" but generally exceed it, tremendously.
Sent from my MB860 using XDA Premium App
Click to expand...
Click to collapse
I don't know about everyone else but my led starts getting hot after only having it on for ~10 seconds. I try not to leave it on because of the heat. But yah I do leave it on for more than a minute all the time so it was probably the specific app causing a rare OS bug that caused it to crash.
I just found this out yesterday but the Note 2 has a separate controller for gathering sensor data.
In short, unlike previously where the CPU had to wake up to gather data, a dedicated low power processor takes care of this!
It works for the accelerometer, magnetosensor, and orientation sensors for sure.
It may also work for the other ones.
Source: Samsung SGS2 Note Development Engineer i talked to yesterday at Samsung's Tech Fair
Interesting. I wonder if that's partly why it gets such fantastic battery life?
Sent from my SGH-T889 using Tapatalk 2
Instead of waking up the whole phone it uses a low-power unit for sensors?
It sounds plausible.
Like when you move your hand above the front sensors when the phone's locked, and half of the screen lights up for a few seconds.
Handwritten from my GT-N 7100
how about the wifi and bluetooth? if i turn on the wifi and bluetooth all the time, will i get less battery drain than other device?
Olaeli said:
Instead of waking up the whole phone it uses a low-power unit for sensors?
It sounds plausible.
Like when you move your hand above the front sensors when the phone's locked, and half of the screen lights up for a few seconds.
Handwritten from my GT-N 7100
Click to expand...
Click to collapse
yes that is exactly one of the features it enables without destroying battery life
dseo80 said:
yes that is exactly one of the features it enables without destroying battery life
Click to expand...
Click to collapse
And I guess, the Smart Stay, which checks on you every now and then when looking at the screen.
Olaeli said:
And I guess, the Smart Stay, which checks on you every now and then when looking at the screen.
Click to expand...
Click to collapse
Doesn't Smart Stay use the front-facing camera? I understand that the camera isn't a sensor, as opposed to the proximity and light sensors beside it (correct me if I'm wrong...)
MarionCast said:
Doesn't Smart Stay use the front-facing camera? I understand that the camera isn't a sensor, as opposed to the proximity and light sensors beside it (correct me if I'm wrong...)
Click to expand...
Click to collapse
Smart Stay pushes the CPU freq to 1600 (aka max freq) every time it has to check.
I don't use smart stay.I prefer a longer battery life.
Sent from my GT-N7100 using Tapatalk 2
DanDroidian said:
I don't use smart stay.I prefer a longer battery life.
Sent from my GT-N7100 using Tapatalk 2
Click to expand...
Click to collapse
if u never idle til the timeout, smart stay wouldnt activate and no battery drain
emprize said:
if u never idle til the timeout, smart stay wouldnt activate and no battery drain
Click to expand...
Click to collapse
Once it activates, does it continue to check at the regular intervals you have set?
Sent from my GT-N7100 using Tapatalk 2
DanDroidian said:
Once it activates, does it continue to check at the regular intervals you have set?
Sent from my GT-N7100 using Tapatalk 2
Click to expand...
Click to collapse
afaik it only check when u idle til timeout, so if u keep interact, it should be no extra battery drain
never knew this, great find
It makes sense. That's how it keeps the accelerometer on to let you know when you a missed call or message. And also led notifications hehe. Makes sense to me! And I'm glad they did it this way.
Sent from my GT-N7100 using Tapatalk 2
emprize said:
afaik it only check when u idle til timeout, so if u keep interact, it should be no extra battery drain
Click to expand...
Click to collapse
It also shows a little eye symbol in the status bar when it does it. Just before the screen dims it checks to see if someone it looking at it then again just before the screen turns off.
DanDroidian said:
I don't use smart stay.I prefer a longer battery life.
Sent from my GT-N7100 using Tapatalk 2
Click to expand...
Click to collapse
I have smart stay turned on and i don't notice any real difference in battery life.
Sent from my SGH-T889 using Tapatalk 2
Chrissssssss said:
It also shows a little eye symbol in the status bar when it does it. Just before the screen dims it checks to see if someone it looking at it then again just before the screen turns off.
Click to expand...
Click to collapse
busab said:
I have smart stay turned on and i don't notice any real difference in battery life.
Sent from my SGH-T889 using Tapatalk 2
Click to expand...
Click to collapse
Thanks to everyone for that!
Explained well! And I'll definitely use it from now on! It seems it might possibly use less battery to use this feature than having to tough the screen sometimes to stop it from turning off, and if you're not looking at it, it will just turn off like it normally would.
Basically, I have my timeout set to 1 minute.
Normally, I have to scroll up or down when I see the screen get dim moments before turning off. That's annoying, and sometimes probably spend more time touching the screen and messing something up when trying to do that.
With Smart Stay, if I'm looking at the screen, it checks for a split second (and you see the little "eye" symbol pop up) and it never dims out out either. That is really nice, and I don't have to keep messing with the screen to make sure it doesn't time out, which probably saves battery too. It continues to check for a split second every 1 minute.
If I'm not looking, it simply turns off.
Will definitely be using it from now on!
I also tried the feature where the red glowing sensor stays on ALL THE TIME WHEN THE SCREEN IS OFF and you can wave your hand over it to see missed calls, song playing, status bar, etc...
I'm gonna pass on this last feature. Not very helpful, and that must drain your battery somewhat faster, as you can even see the red glowing sensor on all the time when the screen is off. No thank you.
Sent from my GT-N7100 using Tapatalk 2
smart stay i suppose only uses the ffc when your phone is about to sleep. if you set it to 1 min, it'll check every min, 5 min, every 5 min. i don't think it'll use much battery.
the only problem i have with smart stay is that even when i lay it down on my talbe in front of me while browsing on my pc, it wouldnt' sleep. i need to place it away from my face so the ffc can't see my eyes.
For a few years now, there has been another core or companion core in smart phones that handles minimal situations. It is a low power core that does not require the resources of the main processing unit. Tegra calls it “4+1” technology which means there are 4 cores running at the same speed and a slower fifth core that can handle most of what you’d be doing on your device. Here is their comments:
http://blogs.nvidia.com/2012/02/technology-formerly-known-as-vsmp-gets-a-new-stage-name-4-plus-1-2/
VSMP has been around for years and Samsung has used it in their system architecture. Back when one of the big things was increasing processing power one of the big problems was dealing with the low power core.
It just doesn't make sense to use power when you don't need it. Its like the V8 engines which drop to 4 cylinders at the traffic light to reduce gas consumption.
Sebring5 said:
For a few years now, there has been another core or companion core in smart phones that handles minimal situations. It is a low power core that does not require the resources of the main processing unit. Tegra calls it “4+1” technology which means there are 4 cores running at the same speed and a slower fifth core that can handle most of what you’d be doing on your device. Here is their comments:
http://blogs.nvidia.com/2012/02/technology-formerly-known-as-vsmp-gets-a-new-stage-name-4-plus-1-2/
VSMP has been around for years and Samsung has used it in their system architecture. Back when one of the big things was increasing processing power one of the big problems was dealing with the low power core.
It just doesn't make sense to use power when you don't need it. Its like the V8 engines which drop to 4 cylinders at the traffic light to reduce gas consumption.
Click to expand...
Click to collapse
I think there is a difference here as the GS3 does NOT have this feature, you can test this by turning "smart rotation" off then testing the autorotation speed of both phones - which is how it was demonstrated to me. The Note 2 is noticably quicker.
I guess what im saying as in the OP , it is not part of the exynos SoC at all. The microprocessor is a seperate package on the PCB