Galaxy Nexus Power Analysis: Why chargers can't keep up with navigation
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Please stop selling us features or bigger screens or faster CPU's until you've made a phone that isn't rendered unusable by virtue of a flat battery whenever you use any of its glorious features.
Dear consumers,
Stop buying hardware that has exactly the same flaws time and time again because it has a few new gimmicks.
It makes the phone thicker, but that's a price worth paying. I have one in my HTC Desire Z, and I had one in my G1 before that. They're surprisingly cheap. On the scale of about $15. I had three of them for my G1, so I had no problems going camping for a week, and not having access to a charger.
The issue in this article is different and more serious: the phone gets less power from its charger than it uses. This really has nothing to do with battery life.
Guess some of the Chinese iPhone copycats using Android are following this model to some extent.
Now, I keep my smartphone in my pocket for internet use (like a little computer) but for calls, I use my little Samsung. It lasts about a fortnight with daily use of up to an hour on calls before I have to charge it.
* the early usb portable hard disks i got often had a triple ended usb cable; one end for hard disk, one end for data connection and an extra end to draw extra power for the hard disk. could this be done for charging phones?
* offline maps would reduce the power required for navigation as sucking down data on 3g is power intensive. you can always turn off 3g and use slower 2g for lower power consumtion. perhaps even an option that if they are using voice to turn off the screen completely.
* somehow convince the manufacturers that many don't want a superslim phone. if it's twice as thick with twice or more the battery life then i am really interested! even if it's only as an extra option then a certain amount of people will pay.
* removable batteries. designing for removable batteries makes models bigger and bulkier but they are more useful when you can get and carry spare batteries.
* some form of standard batteries that persisted between makes and models so that people could invest in extra batteries and know that they will work with the next generation?
in 94 i could get a week from a psion pda with 2 aa batteries with no effort getting 40 hours of use.
in 04 i could get 2-3 days from a symbian device pushing it to it's limits.
in 09 i could drain an iphone 3g to zero in about 2 hours.
it just seems we are going in the wrong direction.
(I've spent the last 10 minutes searching google images and the New Yorker cartoon bank for this, but can't find it anywhere – does it ring a bell with anyone?)
I can run the screen at full brightness, 4G and all other radios firing, using Navigation while playing music streamed over 4G onto Bluetooth, and it still charges. I guess the CPU probably isn't pegged at 100% in my scenario but how often does that happen realistically?
My guess is that a lot of the power suck during navigation comes from: - Keeping the screen on - Constantly reading the GPS - Loading new map tiles, traffic data, etc over the radio - GPU rendering at 30fps or so
It's pretty awful carrying around power bricks for portable hard drives, even though your laptop can easily supply the load if needed. Ditto phones and tablets.
And maybe we can all stop using cigarette lighters as DC sources and move to something a little more sophisticated.
I'll argue that our phones need to draw less power in their worst case modes personally.
Its a lot of momentum to fight against; the solution is going to need to be extremely compelling to compete against the existing USB/vehicle DC power solutions.
Rather, the issue is that what is going on inside the phone. In most modern phones the input voltage is fed into a monolithic power management IC which provides the numerous voltages required to run the device, handles power on timings, and often contains the batter charger. The unit in the GN is linked below [0].
There are various ways to hook these up, but a popular method is to only supply the device power rails from the battery. If you've ever ran your phone completely dry, plugged it in tried to power it on, and watched it only start up for a couple seconds and die again, its because the battery didn't have enough charge to get through boot up, which uses a lot of power.
In other words, even when your phone is plugged into the wall, its probably still running on the battery. For the same reason, most newer smart phones can't be powered on without a battery in them. Its also why a phone using a lot of power while plugged in gets very warm around the battery, you are pouring power into the battery just to remove it again, the inefficiencies in the process = heat.
Thus, what it really comes down to is the ability of the phone to discharge its battery faster than it can be charged. The limit of how fast you can charge the battery can be caused by limited power (computer USB port), limits in the charger or simply by the physics of charging a li-ion without causing damage to the battery or the user.
In this case, without doing the math on it, ~5W is probably about the limit of the charging IC linked below, depending on charging mode. Just a guess though, it could also be the limit of the batteries ability to charge.
I have seen phones that can really switch to running on actual input power, but these seem to be less common now. It requires addition components in the form of a power switch and often a regulator. More importantly it takes board space and costs money.
Besides, with an install base that numbers in the hundreds of millions and most of which have well over a decade of useful life.
Instead, the voltage can vary depending on the state of the car's engine, the car's battery, whether or not you're currently hooking up a second battery in order to jump-start your car, and so on.
It's not very sophisticated when considered as a source of 12 V DC, since it has these other parameters that are not something you'd generally expect a clean and simple power source to have.
Some quick looking doesn't show any details of the max power rating unless you buy a copy of the spec for 45 Swiss francs.
"I'd love to test the side charging pins but I don't know the pinout or if it needs to communicate to draw full power."
I have not had much chance to test this on my GSM galaxy nexus but I have not noticed this problem so far.
I've had the original Nexus, Nexus One, Nexus S and wanted to buy the G Nexus but if google/samsung are willing to put a device that can't function under normal operating environment, then they shouldn't have done at it all.
See, with the iPhone (4S), I know Apple would never put out a device like this. It might not have things like a notification LED that blinks when u have a message, but the thing is bullet proof -- it just works.
The mentality is certainly different. I want a finished product, and not be a beta tester for a company.
It's no accident Apple sticks to their time-proven design: small 3.5" screen, no LTE, etc.
And as I get more busy with my life (business, etc), I could careless about the "openness" of the Android platform--it's not like I'll be compiling ROMs all day.
I just want something that works and won't let me down in the 11th hour and with Apple I know that won't happen.
I've only had my iPhone 4S for a week, but I haven't noticed anything drastically worse than my iPhone 4.
It certainly hasn't ran out of power during the course of a day yet.
- Around 1 hour surfing, reading feeds, playing games
- Around 5-10 minutes calls (GSM or Skype)
- Around 1 hour with music (screen off)
- Checking time, emails, or message with it (10-12 times a day)
The battery lasts for one day. I learned to charge it every night. My cousin has an iPhone 4 and it's almost the same thing.
I am wondering which manufacturer will be the first to deliver a decent smartphone that works for one week, that'd probable one of the best selling smartphones ever sold..
I can charge my phone in under an hour. I can do so in the car, at my desk, or any of hundreds of other places given the ubiquity of micro-usb. For me, once I can go all day on a charge any excess capacity just means more weight/bulk.
A week-long battery would be obscenely large, the phone unnecessarily heavy all while providing nearly zero benefit to my use case.
Now: god forbid if i forget my charger when on business trips!
Battery tech is constantly advencing too, but instead of using that extra power for longer battery life they put in more useless stuff. Who needs a fing barometer in his mobile!?
It does, you can use the camera flash as a notification LED (it's under the Accessibility settings).
While running a full blown GPS app, talking on a conference call with Bluetooth, and using live traffic so the data connection is running as well, the iPhone 4 gains about 1% charge per minute with a 2 AMP charger.
My relatives frequently drive from Chicago to Omaha to visit family. Presumably because of poorer reception in Iowa they cannot use Google Maps even when plugged in because the phone still discharges.