yashsingh1/xdaforums huggingface dataset:
[Fascinate Android Development] beray5:
"Power usage would increase by a factor of 4 if the resistance of the transistors in the processor were changing. However, the resistance of the transistors is relatively constant, so power consumption should change somewhat linearly as voltage is raised/lowered."

Increase voltage also altered the FET fundamental biasing -> shifting transconductance performance curve.

upload.wikimedia.org/wikipedia/commons/thumb/d/d7/IvsV_mosfet.png/800px-IvsV_mosfet.png

----------------------------

"Read on, it says that was in my words. He talked for about 15 minutes explaining... Try typing 15 minutes of explanation, see how big of a novel you write."

How would increasing "Biasing Voltage" allowed for less power consumption?
[Fascinate Android Development] adrynalyne:
Sadly, degrees are no match for common sense. I will take my common sense over your buddy's degree, kthx.
[Fascinate Android Development] imnuts:
+1 I know people with the same degree that I have and their knowledge of various subject matters I have talked with them about is no where close to what I learned. Just because someone has a degree in something doesn't mean they know any more than a random person off of the street.
[Fascinate Android Development] soba49:
Quick advice to yutsoku: Just drop it. You probably feel like people are insulting your friend without warrant. Let it go anyway. Thanks for your post, your input has been registered. I was minorly flamed for implying that UV kernels run a higher minimum clock speed.

Though I would really like to have a ready explanation for what conditions cause one kernel to outperform another, the most important thing to me is finding the configuration that gets me the most hours of use for a day.

So, on to that.

System Configuration. Blackhole v3.0, DL09, Adrynalyne 1/16.

Extras: live wallpaper (Ocean Waves), ADW, auto brightness, buzzbox news (updates every 30 minutes on wifi or 120 minutes 3G), accuweather quick, tweetdeck (updates every 60 minutes), google voice default theme. Gmail (push updates roughly every 15 minutes),

charged to 100% in the evening, and left unplugged overnight - no battery conditioning of any kind, nor any battery saver apps.

Report 1/17 - UV Novoodoo Kernel Day 1 mixed WIFI and 3G usage:

@80% Part 1 (first 20% of battery used)

Time Tot.: 10:04:11 = 33:46 display + 9:30:25 idle

6% - display (30%):

1.5% - standby (43%)

7.1% - standby NS: (83% no signal)

4.4% - idle:

1% - android + XDA App

@45% Part 2 (first 55% battery used)

Time Tot.: 15:42:01 = 1:28:30 display + 14:13:31 idle

22% - display (41%)

5.8% - standby

10.7% - standby NS (65% ns)

8.8% - Idle

1.7% - Maps

1.1% - voice (34 second call)

4.9% - android, etc

@ 3% Part 3 - (97% of battery used)

Time: 22:08:17 = 3:43:46 + 18:24:31

53.4% - display (53%)

11.5% -standby NS (54% no signal)

10.8% - cell standby (22% total)

10.7% - phone idle

10.6% - Android (3% of total), dolphin 3%, XDA 2%, phone calls not reported

Note: For cell standby I broke out no signal from otherwise. So for part 3 it was reported at 22% of the 97% usage that day with signal available only 54% of the time, 21.3% = 11.5% + 10.8%

In brief, 224 minutes of actual phone use sapped 53% battery, or about 14.3% per hour. 1104 minutes of standby sapped the remaining 47% battery or about 2.5% per hour. Part 1 and 2 are provided for your reference. Not as good as I used to get (http://xdaforums.com/showthread.php?t=861091), but not bad either. That said, my 'no signal' is about 3X as bad as usual, so I'm probably due for a *228.

Thank you for the SV kernel, adrynalyne.
[Fascinate Android Development] beray5:
Have you tried straightening up your battery charging calibration yet?

If not, then let your phone drop down to 20% charge and preferably less before plugging back in for a complete 100% full cycle charge. At the most you'd have to to is performing it twice in a row to correct the problem.
[Fascinate Android Development] J Shed:
You're clearly paraphrasing something you know nothing about.
[Fascinate Android Development] RacerXFD:
Seriously, this should be for learning rather than flaming. So please be kind. Thanks.

Swype is the bane of my spelling.
[Fascinate Android Development] mattstakilla:
reading everything in monotone makes it sound less hostile
[Fascinate Android Development] codeman0624:
I've been reading this thread, and all the theories are interesting, but I don't think anyone has hit on the main point of what dissipates the power.

en.wikipedia.org/wiki/CMOS#Power:_switching_and_leakage

(I can't yet post an actual link, post count isn't high enough)

The processor is made of millions of MOS transistors. They only dissipate power when they're switching...there's no static power dissipation at all (except for leakage, but that's usually minimal compared to switching power). So naturally the faster they switch, the more power you'll be using. The equation works out that the power dissipated is proportional to frequency, and proportional to the square of the voltage. So in theory, cutting the voltage in half would lower your power by a factor of 4. (that factor of 4 the other guy was talking about probably)

The only problem is, the people who designed this knew the fabrication process they were using, and thus knew the threshold voltages and other characteristics of the transistors themselves...so they chose an operating voltage they knew would work, accounting for any variations in parameter shifts of the transistors during different fabrication lots. So you could go ahead and lower the voltage and you may be lucky to have a chip in your phone where the parameters for every transistor were on the "good" end, and you'll see a great power savings.

But the more likely scenario is you'll just end up causing bit errors, causing your processor to flush what it was doing and have to start over to try again...which is bad for battery life.

Sorry for the wall of text, that's just by 2 cents about the matter. I'm sticking with a standard voltage kernel.
[Fascinate Android Development] iofthestorm:
That's pretty true, although these days at the really small manufacturing nodes like 45nm leakage current is actually quite high because the threshold voltage drops. You definitely cannot ignore leakage current anymore.
[Fascinate Android Development] codeman0624:
Yeah, you're right. I was just basing that statement off my 0.18um design experience.
[Fascinate Android Development] RacerXFD:
So does that mean under volting is good or bad?
[Fascinate Android Development] iofthestorm:
As with many things, there is no one answer. Undervolting is using the cpu outside of its normal parameters. A modest undervolt will probably save a little battery life, and an aggressive one might cause a lot of problems. Test and see which works for you. There are many sources of variation that could cause one kernel to work great for some phones and terrible for others.

From a purely theoretical perspective, undervolting will definitely cause it to consume less power though.
[Fascinate Android Development] fascinated512:
I've been following this thread pretty closely because battery life is a huge issue to me. I have the extended battery on mine (ugly as it may be), underclocked to 800 mhz tops with 100 mhz minimum, drop brightness down all the way including using screen filter to go even dimmer, and use the phone like crazy. I have been through probably 15 different kernels, nonvoodoo and voodoo. After finally settling on the -100 mv imnuts voodoo5 kernel as my kernel of choice for battery life, I saw the beginning of this thread. After reading a little bit of your posts, I went ahead and tried out a standard voltage voodoo kernel from adryn. I may not know anything about all the physics behind currents and voltages, but from my personal use (100 texts, 60 min talk time, probably 30 min web browsing, multiple widgets and apps running nonstop), I have found the standard voltage kernel gives me more remaining battery life at the end of the day. At 9:33 PM after being unplugged for 13 hours, I have 74% battery remaining. I think I found the setup for me! That's my two cents...here's what I'm running:

SF, DJ05, Goldenstorm's Blackish ROM, adryn's voodoo5 SV kernel, 2200 mAh extended battery.
[Fascinate Android Development] rw9:
less volts = more amps to power a device

more volts = less amps to power the same device

Before the beating starts - I have NO idea how this applies to phones or mobile CPUs. But in building out datacenters for a living, we always strive to maintain 220v power due to lower amperage and relative costs. It's also a huge factor on UPS battery life. I can tell you that it's a fact that 110v power beats the sh!t out of a UPS battery pack while 220v is definitely better for long term life.

But all of this experience is with constant draw and in a TOTALLY different scenario. Again, just my two cents and it's probably worth less than that.
[Fascinate Android Development] soba49:
1/18 report adrynalyne test 2 nonvoodoo UV kernel:

@8% remaining

Time: 20:06:38 standby = 3:29:05 display + 16:37:33 idle

Display - 56%

Cell standby - 20% (42% no signal)

Phone Idle - 11%

Other: Android 3% + 2%, XDA 2%, Voice 2% (55 seconds), Swype 2%

Spent way too much time on analysis last post, so this is just raw battery info.

Not, I spent a couple of hours today transferring data at 1 bar of signal, which murdered my battery. Although the UV kernel did underperform the SV kernel, I would not give these numbers a lot of significance.

Hitting *228 and switching to test 5 UV kernel NV. Cheers. And Adrynalyne, thanks for again providing a standard volt kernel to compare against. I owe you a foamy beverage.

Edit:

1/19 report, test 5 uv nonvoodoo. Poor signal most of the day again (location, not kernel's fault), so keeping the report brief.

@19% battery remaining

14 hr 43 unplugged / 2 hr 25 minutes display on.

Display 40%, standby 17% (68% w/o), idle 8%, voice 27% (14m:37s), remaining 8% split between xda, android, and dolphin
[Fascinate Android Development] adrynalyne:
Seeing how you guys are on a standard voltage kick, my tests kernels (thread) has both uv and sv stuff.
[Fascinate Android Development] RacerXFD:
I think sv is working well so far. How much under volting is going on in your under volt kernels?
[Fascinate Android Development] iofthestorm:
Yeah, not to shoot you down or anything, but ICs are quite a bit different from UPSes. We're talking voltages below 1.5V, and the differences between UV and SV are in millivolts. The chemistry side of it (battery technology) I don't know anything about, but the EE side I do.

The relations you mentioned at the top of your post would only hold true if power was held constant. That doesn't really make sense here. In a UPS this is true because the hardware burns the same amount of power regardless of the wall voltage. Here we're changing the hardware so that the supply voltage for the transistors is different. The voltage we're talking about is around 1.2-1.5V for desktop CPUs too. Much higher and the transistors will do bad things.

One last thing, I should remind you all that the reason Atom and their ilk and Intel CULV CPUs (guess what the ULV part stands for) consume less power is partly because of the lower voltages. The reason you may or may not see a power benefit on a mobile phone is because there are hundreds of other variables in effect (beating a dead horse at this point I realize...)
[Fascinate Android Development] adrynalyne:
1000mhz=-50mV

800mhz=-75mV

400mhz=-75mV

200mhz=-100mV

100mhz=-100mV
[Fascinate Android Development] RacerXFD:
I also learned from my digital circuits class that it's a subtraction of voltage through semiconductors. The current loss is negligible in digital circuits.
[Fascinate Android Development] iofthestorm:
Err, not at the levels we're talking about. Subtraction of voltage is a very simple model that is used for digital design just to make sure the logic is correct, but you still have to look at currents for any real analysis, such as delay and power calculations. Everything in an integrated circuit has units like micro, nano, pico, and femto, but you can't pretend it's not there.
[Fascinate Android Development] rw9:
I figured as much. Again, I'll state that I have absolutely ZERO knowledge on the way phones actually operate at a kernel / battery relationship level, nor did I major in EE. Just thought I'd throw it out there for the sake of things. Thanks to everyone for the enlightening discussion never the less.

For what it's worth, I'm running Adryn's 1230 voodoo5 kernel and battery life is EXCELLENT. I'm not sure if it's undervolted or not, but it's definitely better than anything I experienced with any of the other DI01/DJ05 kernels that I tried out. I'm interested in his other kernels as of late, but am watching from the sidelines at the moment to see the general concensus on what seems to be more stable for everyone. I ran an undervolted kernel a couple of weeks ago and had all sorts of issues with FC's and lockups, so I'm not big on getting back on that bandwagon. If we find some sort of sweet spot where battery life is great and performance isn't sacrificed, then I'll be the first to give praise. But I think we're seeing a swarm of testing right now that's still seems like there's a ton of guess work involved. I'd just like to see the field narrowed down a bit first I guess...

Ok, I'll go stand in my corner again like a good little troll :)
[Fascinate Android Development] Ardilla:
Hey All,

First post here on XDA. I have thoroughly enjoyed this thread so far. I was wondering if someone wiser than me could set up some kernals for testing. The goal would be to keep everything stock except for the changes. I am pretty sure stock voltage is 1300 mA and I know stock processor speed is 1gHz (adjust my math below if necessary if I am wrong). I would like to see:

UV + OC

A 10% decrease in voltage (1170mA) + a 10% increase in clock speed (1.1gHz)

UV + UC

A 10% decrease in voltage (1170mA) + a 10% decrease in clock speed (900mHz)

OV + OC

A 10% increase in voltage (1430mA) + a 10% increase in clock speed (1.1gHz)

OV + UC

A 10% increase in voltage (1430mA) + a 10% decrease in clock speed (900mHz)

Now, I know the 10% increase is possible in the processor but I do not know if it is possible or reasonable in voltage so numbers could be changed to to better reflect hardware capabilities (5%?). But, the key here is equivalent ratio change. I would like to see these kernals created so that I (or someone else) could test the battery life effect.

Hopefully this research plus the expertise of the people on this forum we can find the sweet spot for performance and battery life on the Samsung Fascinate.
[Fascinate Android Development] iofthestorm:
Hmm, this thread inspired me to write up a basic introduction to digital integrated circuits for technically minded people. I might throw up a draft in the next couple days. It would just assume basic electronics knowledge (what are Rs and Cs, Ohm's and kirchoff's laws) and start from transistors to the logic level and maybe some big ideas in computer architecture like pipelines, memory hierarchy, etc. No promises I guess, I am fairly busy but it would be an interesting exercise for me as well.
[Fascinate Android Development] RacerXFD:
Thanks, this would be awesome... A geek can only understand so much specs without understanding the actually mechanics.
[Fascinate Android Development] fascinated512:
Every SF is going to be different when it comes to which style and type of kernel works the best. Personally, I'm on my 38th unplugged hour of use and still have 30% battery remaining with the standard voltage. I'd say it blows the UV out of the water!
[Fascinate Android Development] RacerXFD:
Yea, I've been using sv all day with games, e mails etc. not sure, but I like my SV. But it could be that battery fix in general section that may have done it too.
[Fascinate Android Development] agsded:
I've only ever run two rom/kernels on my fascinate. The stock rom/kernel, and the DL09 super clean with the 1230 voodoo kernel adryn had attached to the stock DL09 rom. I believe its UV, but I'm no sure. I had a few weird random reboots at first, but I believe it was caused by app issues, cause I've had a few updates since then, and haven't seen a random reboot since. Anyways, my battery life has improved significantly, typically my phone goes off charger at 10 am, and at 5pm when I'm getting off work, its uusally between 30-40 percent. Since flashing adryn's super clean an kernel, I've been between 60-75 percent battery every day at 5 now, depending on how much I use it. Not sure how much is attributable to kernel am how much to rom, but my bat life is much better now.

Hey, Adryn, any appreciable reason you can see for me to move to one of your newer kernels?
[Fascinate Android Development] uslacson1:
I don't think we can generalize battery life just based on UV, SV or OV.

It seems to me that even the type of rom and themes also affect battery life.

I've tried different UV kernels and not get the same results.
[Fascinate Android Development] soba49:
Though I don't endorse that you can generalize between different kernels/roms/installations/usage areas etc., it probably is possibly to do reasonable battery life testing between the pairs of kernels Adrynalyne just posted. It's just difficult to keep the tests fair, and also difficult to keep the reporting fair.

It would be worthwhile to discuss what would be a fair test. Ie. download and watch a particular video on youtube, open a web page 30 times, etc. as a benchmark.

That said, I LOVE the test5 SV kernel (nonvoodoo). Just got my best [subjective] battery life yet, for any kernel. Mind you the phone spent the entire period bathed in a strong WIFI signal, and I don't have a comparison test for an undervolt kernel in the same conditions. These UV kernels are the best UV kernels I've tried... I just keep getting slightly better numbers out of the SV ones, for unknown reasons. (Side note: my previous guesses as to why UV kernels don't outperform for me all appear to be false based on OSMonitor readings).

1/21 & 1/22

6% remaining

Total Time: 33h:02m:42s = 4:30:37 display on + 24:04:32:04 idle

display (36%), voice (30%), standby (16%), idle (10%), android system (2%), XDA (2%) other apps (4%)

40m:19s of voice calls, 14% without signal

[I previously posted configuration. Blackhole 3.0 with a few frequently updating data apps, live wallpaper, auto brightness, very little audio use, radio, gps, and WIFI were all on for the full period - haptic was on 1/21 and turned off 1/22, haptic and audio feedback seem to eat a noticeable amount of battery]
[Fascinate Android Development] beray5:
1000mhz=-50mV

800mhz=-75mV

400mhz=-75mV

200mhz=-100mV

100mhz=-100mV

Based upon givens above, my phone on UV power consumption is at best possible while idle doing nothing. After 9 hrs on the night stand my phone lost 3% battery charge each time for 2 nights in a row, I guess Samsung didn't lie when they stated "up to 300 hrs".

Previous test on DI01 stock was 5% lost each time for 2 nights in a row.
[Fascinate Android Development] RacerXFD:
So are you getting better results with under volting?
[Fascinate Android Development] garywojdan81:
So far I have tried Adrynalynes voodoo kernels wirh great success. But what I notice with my set-up is that the uv kernels are better on standby consumption & the sv kernels are slightly better on consumption under heavy usage. The best one for my battery life is his 1/16 sv_voodoo. On any of them though, it takes me a couple days to really gauge performance.
[Fascinate Android Development] soba49:
I agree. Significant improvement in overnight battery life for UV kernels. For my usage the SVs last longer, but use up maybe 50% more overnight (ie. 8% vs. 5%)
[Fascinate Android Development] destroyerbmx:
I always use my phone, I bought it to use it so I am currently running an SV kernel, I did notice bad battery life all around with UV but also my phone acts funky with one, from day 1 since I got the phone I have been running UV kernels and in the last 3 days I started running SV kernels and I am noticing all the funky things the phone did and random freezes for a min are gone.
[Galaxy S I9000 Themes and Apps] Kalifax:
Dear devs, theme-makers and users. Anybody know if there is a theme with the gingerbread screen off animation?

Would love it on my sgs...
[Galaxy S I9000 Themes and Apps] GuestK001:
+1 :)

I want it too.
[Galaxy S I9000 Themes and Apps] celeronix:
Gingerbread screen off animation is not available yet.
[Galaxy S I9000 Themes and Apps] dyallo:
Well apparently CM7 has it.

I want it too! Will donate
[Galaxy S I9000 Themes and Apps] Daneshm90:
It's not impossible, but its not feasible either.

Considering you're dealing with closed source and want to add opengl based code to a smali file, it could be tricky and definitely time consuming.

I'd advise just sit tight for a stable gingerbread firmware.
[Galaxy S I9000 Themes and Apps] jaju123:
Cm7 has it because it is gingerbread...
[Galaxy S I9000 Themes and Apps] st4rk:
They also added it to screen on so it must be transferable in some shape or form.. No idea how myself..
[Galaxy S I9000 Themes and Apps] NargalaX:
I have been wondering about this for days now, and I would love to see it on my vibrant :D
[Galaxy S I9000 Themes and Apps] calexus1182:
I would totally show that off :D to the best of my knowledge no phone has such a cool feature
[Galaxy S I9000 Themes and Apps] KLoNe1:
Yeah, everybody is looking for it. +1 to seeing it soon! :D
[Galaxy S I9000 Themes and Apps] vinivius:
+1 i want it too...
[Galaxy S I9000 Themes and Apps] trixnix:
Me tooo!

sent from my Samsung® Galaxy S
[Galaxy S I9000 Themes and Apps] HazzBazz:
Any ideas? Supercurio spoke about it before
[Galaxy S I9000 Themes and Apps] NaabKing:
I would want it too :D
[Galaxy S I9000 Themes and Apps] KLoNe1:
+1 very keen for this! :) (+caps!)
[Galaxy S I9000 Themes and Apps] ADeadlySpoon:
Surely with so much hype over Gingerbread, this must have been found by someone?

I hope someone finds it soon and is able to implement it.
[Galaxy S I9000 Themes and Apps] DJ_GLiTCH:
What really annoys me about this awesome feature is that an iPhone already has the ability to do it (albeit with a mod from the jailbroken community) after some guy spent 3 hours figuring out a solution. You'd think it'd be a lot easier for android phones (since it was originally, well, has been already designed for them) to support and implement it much better than an iPhone... well, that's just my opinion. I'm not too sure how easy it would be to make it work for our phones, and I'm more than happy to wait until someone wise can take the time to make it happen, but either way when it does eventually arrive you can count on me to add it onto every future rom I'll ever use. :D

ps. I'd link you all to the article about the iPhone mod but I don't have the rights to at the moment... sorry.
[Galaxy S I9000 Themes and Apps] Dioser:
In norm terms

I wouldn't use trans, and I don't at the moment, no need to flash, just pure speed XD

But that said, I must admit, this I'll prob use :D Neat how it looks like an old analog television turns off, or this is what it makes me think of,

Nostalgia on Hightech
[Galaxy S I9000 Themes and Apps] scheichuwe:
You all just have to read post #5.
[XPERIA X8 Themes and Apps] danielfonseca890:
CARBON THEME​

This theme is a edit of gingerbread and some anothers themes from x10 you can see some pics of theme on attachments. :)

What you need to have:

- root

- busybox´

- framework-res.apk from attachment

How to install:

Use this method to change your framework :) ->

http://xdaforums.com/showthread.php?t=889963

Widget's:

Dazzle - http://www.androidzoom.com/android_applications/tools/dazzle-configurable-switcher_frdy.html

Information: The home screen theme is not include on framework i use Adw.Launcher Ex to change , if you want the adw theme is called "Phone7 Theme". ;)

Have Fun :D
[XPERIA X8 Themes and Apps] Buddha:
not bad ;D

good work :)
[XPERIA X8 Themes and Apps] Tobi@s:
The quality of the icons is very bad... I'll switch back to my HTC Framework