What's your power budget?

[schettj]

http://ppc6700users.com/forums/viewt...hp?p=7820#7820

I'm sure some of you know about this nifty tool - acbPowerMeter-0.5.1, but for those that don't it will really open your eyes as to what kind of battery life you can expect out of your ppc6700.

Some interesting tidbits I have learned just by running it on mine, sitting next to me @ work...

My normal power-up usage is 71mA - doing nothing but turned on, backlight at tick 5 from the right, EVDO connected but dormant. Moving the backlight 1 tick brigher costs about 3-4mA per tick...

Quick refresher on mAh, mA, and so on (from http://www.proz.com/kudoz/1053537)

a 1350mAh battery can suppy that much mA for 1 hour, or
135mA for 10 hours, or
67.5mA for 20 hours, or
33.75mA for 40 hours...

So, my "powered on, backlight on, doing nothing but EVDO idle" mode is good for about 19 hours. Not very useful, but good.

When the backlight goes out, but it's still "on" you can dimly see it pulling right around 40mA.
That mode is sustainable for 33 hours or so.

Interesting spikes - doing an email check (no new mail) was nearly 400mA, for a 30-60 seconds... that's a pretty decent hit - pretty much you're drawing in this ballpark when you surf, or more if you have your backlight cranked up.

EVDO use (at least on mine) can be sustained for 3:20 give or take.

A voice call clocks in at about the same power at first, but unlike surfing the backlight goes off after a bit, dropping 30-40mA off the load, and the CPU goes into a low power mode (the radio is doing most of the work) which gets us around 270 - 300mA, or 5 hours talk time.

Finally, I disabled power off completely, and turned off the Screen (InClose can do that - it's on, but the screen is fully off) - that's as close to "standby" as I can get while keeping the CPU on so the app actually runs.

I'm leaving it in that mode now - will check on it in an hour and post the results.

In the mean time, this is how you can think of it
Each minute of talking is 1/300th of your battery (.33/min, 20%/hour)
Each minute it's unplugged is 1/2000th of battery (.03/min, or about 2%/hour)
Each minute you have the display on is 1/1140th (.05/min, or 3%/hour)
Each minute of *active* EVDO is 1/200th (.5/min, 30%/hour)

So, you can mix and match for your average usage to find out what your budget is. If you go 16 hours between charges, that's 32% of your battery. Add in 30 minutes of talking, 30 minutes of data, and you're at about 57% of total. Gives you an additional 33% to vapors to use as you see fit There's a bit of overlap in these numbers which I didn't figure in, but they're within 10% of the total I would expect.

For me, I have mine check email every hour, so thats 16*2 or 32 minutes of data or 15-16% of my battery right there, every day. Plus the standby cost of 30% or so for the day, and on a light-use day I should hit the charger at the end of the day between 45-55% of battery - which is about where it lands unless I top it off.

Interesting stuff!

Ok, well it took a while to type all that in, and lunch, and here is the "screen off" results:

45 minutes running, 27mA drawing, average 36mA over 45 minutes, 3 short spikes to just under 300mA, 24mAh used, battery at 90%

So the "just standing by" draw is probably in the ballpark of 20-24mA, or 56:15 run time, or .02%/min, or 1.8%/hour, or 28.8% of the battery every 16 hours for me, doing nothing but passive EVDO, hourly email check on 2 IMAP accounts, and phone on... So yep, about what i had before. For me, I can also do a couple hours of surfing and/or talking total, and the usual actual use as a PDA, and I'm out of juice

Oh and for fun...
Bluetooth on - couple extra mA, not bad.
Wifi on - 300-idle, 400-600mA pulling data (WHOA! killer there vs EVDO is that the "standby" wifi is burning 3% a minute - just being on. Yikes.)

[jamaa124]

good info!

[colonel]

Yep, very useful app. That is why I included it in my rom. It is really good at helping people who have complaints about battery consumption. All you have to do is let it run for a while and use the device normally and you can see exactly what is eating your battery.

[thejtiggidy]

I cannot run this on my 6700 with 3.3 for some reason. It doesnt require .net does it?

I was able to run it before on a older sprint rom

[schettj]

Dunno - I have .NET1.0 installed on my 3.3 rom