Editing N900 Hardware Power Consumption

Warning: You are not logged in. Your IP address will be recorded in this page's edit history.
The edit can be undone. Please check the comparison below to verify that this is what you want to do, and then save the changes below to finish undoing the edit.
Latest revision Your text
Line 12: Line 12:
* WLAN transmit 802.11b - 150 mA
* WLAN transmit 802.11b - 150 mA
-
Battery parameters can be monitored thru fuel gauge chip TI BQ27200 [http://focus.ti.com/lit/ds/symlink/bq27200.pdf]
+
Battery parameters can be monitored thru fuel gauge asic TI BQ27200 [http://focus.ti.com/lit/ds/symlink/bq27200.pdf]
==Some preliminary numbers using [[N900 Hardware Charge Meter|the battery monitor chip]].==
==Some preliminary numbers using [[N900 Hardware Charge Meter|the battery monitor chip]].==
-
These numbers are biased, and represent best cases. Some have had outliers which may be normal and unavoidable current spikes removed. This is under the assumption that the minimal power represents the minimum power achievable, and it should long-term be possible to - possibly with software patches - achieve these. +x indicates the measurement is for that element only. A raw measurement has no + (marked "T"), and is a total consumption of whole device, when operated in that state. Unless otherwise mentioned, numbers are for the idle locked case, with screen off, battery voltage "full" = 4.0 to 4.1V.
+
These numbers are biased, and represent best cases. Some have had outliers which may be normal and unavoidable current spikes removed. This is under the assumption that the minimal power represents the minimum power achievable, and it should long-term be possible to - possibly with software patches - achieve these. +x indicates the measurement is for that element only. A raw measurement has no +, and is a total. Unless otherwise mentioned, numbers are for the idle locked case, with screen off.
Assume  
Assume  
-
* Suspend (echo mem >/sys/power/state), wifi and GSM off. 2 mA T *)
+
* Suspend (echo mem >/sys/power/state), wifi and GSM off. 2 mA
-
* Suspend, GSM on, connected to 3G (2 bars) 5 mA T *)
+
* Suspend, GSM on, connected to 3G (2 bars) 5 mA
-
* Suspend, GSM on, connected to 2G. (2 bars) 3.6 mA T *) 
+
* Suspend, GSM on, connected to 2G. (2 bars) 3.6 mA
-
    *): states not recommended, used for test purposes only
+
* Idle, no SIM, wlan off 7 mA@4.1 V
-
* Idle, no SIM, wlan off 7 mA@4.1 V T
+
* Wifi on with maximum powersaving. +~2 mA
* Wifi on with maximum powersaving. +~2 mA
-
* BT enabled, no headset connected +2 mA with ~1/5 time spikes to +9 mA
+
* MMC card in. Under 1 mA
-
* MMC card in. Under +1 mA
+
* Xchat running, sporadic traffic. +8 mA
* Xchat running, sporadic traffic. +8 mA
* Screen on, no backlight. +80 mA
* Screen on, no backlight. +80 mA
-
* Backlight on max +150 mA, +40mA on 4 of 5 steps in simple brightness applet & low ambient (/sys/class/backlight/acx565akm/brightness = 63)
+
* Backlight on max +150 mA
-
* Media player playing MP3, one step above mute. 110 mA T
+
* Media player playing MP3, one step above mute. 110 mA
-
* Vibrator at max +120 mA
+
* Vibrator at max +100 mA
-
* md5sum /dev/zero 250 mA T
+
* md5sum /dev/zero 250 mA
-
* md5sum /dev/mmcblk1p1 - 1G SD card. 240 mA T
+
* md5sum /dev/mmcblk1p1 - 1G SD card. 240 mA
-
* md5sum /dev/mmcblk0 - internal MMC 240 mA T (these indicate the CPU is somewhat idle, waiting on IO, and this counteracts any increased power use by the memory)
+
* md5sum /dev/mmcblk0 - internal MMC 240 mA (these indicate the CPU is somewhat idle, waiting on IO, and this counteracts any increased power use by the memory)
-
* camera active, showing preview. (backlight off) 210 mA T
+
* camera active, showing preview. (backlight off) 210 mA
* GPS - location test gui - in continuous GPS recieve mode - +50-80 mA
* GPS - location test gui - in continuous GPS recieve mode - +50-80 mA
* 3G connected, good signal, no data or other activity +8 mA.
* 3G connected, good signal, no data or other activity +8 mA.
* 2G connected, good signal, no data or other activity +5 mA
* 2G connected, good signal, no data or other activity +5 mA
 +
===2G data, short pings===
===2G data, short pings===
-
(all Total - ATTENTION, these values depend on distance from device to base station and thus how much TX RF power it needs)
 
* 1 s ping 130 mA
* 1 s ping 130 mA
Line 67: Line 65:
3G recieving at 200 k/s 275 mA
3G recieving at 200 k/s 275 mA
-
==random adds:==
 
-
===2x bash infinite loops, by frequency===
+
--
-
* 250MHz 278mW T
+
random adds:
-
* 500MHz 524mW T
+
-
* 805MHz 903mW T
+
-
* 900MHz 1064mW T
+
-
So it seems like the power saving cpufreq hacks are largely irrelevant and one would always use ondemand for maximum CPU peak throughput. Needs further testing with irregular I/O-dependent load tho.
+
WLAN PS-mode medium,10 mW, ssh login active, local xterm with bq27200 script loop -9, screen blanked, aggressive custom breathing indicator light: 20 mA
-
 
+
-
'''NOTE: everything >500MHz WILL destroy your CPU long term, due to overheating and EM''' This is as evident as the rule "You shall not operate 12V incandescent Lamp at 15V or 20V"
+
-
--[[User:joerg_rw|joerg_rw]] 12:28, 13 May 2015 (UTC)
+
-
 
+
-
WLAN PS-mode medium,10 mW, ssh login active, local xterm with bq27200 script loop 20, screen blanked, aggressive custom breathing indicator light: 20 mA
+
xchat 8 freenode chan, wifi PSM medium, screen locked:
xchat 8 freenode chan, wifi PSM medium, screen locked:
Line 101: Line 90:
18:40 4087 99  99  -64  1180 1180 1180 65535 3403  36  0
18:40 4087 99  99  -64  1180 1180 1180 65535 3403  36  0
</pre>
</pre>
-
 
-
7mAh / 4min = 7*60mA_min / 4min = ~105mA(h/h);  obviously depends a lot on IRC activity during test period
 
-
 
-
===A script to monitor the power consumption for a minute using bq27x00_battery===
 
-
 
-
The shell script using i2cdump affects measurements a lot so it's better to use the kernel module.
 
-
 
-
'''CITATION NEEDED! Why should a shell script and i2cget be inferior to a perl script and a deprecated kernel module?
 
-
--[[User:joerg_rw|joerg_rw]] 12:18, 13 May 2015 (UTC) '''
 
-
Go measure it yourself.
 
-
[[User:l29ah|l29ah]] 23:40, 14 May 2015 (UTC)
 
-
this only would show that the kernel module and/or the perl script are buggy. Actually the chip is better in doing sum than a script, it has registers for that and works completely transparent without any sw attention--[[User:joerg_rw|joerg_rw]] 14:26, 16 October 2017 (UTC)
 
-
<pre>apt-get install perl</pre>
 
-
<pre>
 
-
#!/usr/bin/perl
 
-
use strict;
 
-
use warnings;
 
-
use List::Util qw(sum);
 
-
sub mean { return @_ ? sum(@_) / @_ : 0 }
 
-
my @pa;
 
-
for (my $i = 0; $i < 15; $i++) {
 
-
open(my $cf, '<:encoding(UTF-8)', '/sys/class/power_supply/bq27200-0/current_now');
 
-
open(my $vf, '<:encoding(UTF-8)', '/sys/class/power_supply/bq27200-0/voltage_now');
 
-
my $cc = <$cf>;
 
-
my $vc = <$vf>;
 
-
my $pc = $cc * $vc / 1000000000; # mW
 
-
push @pa, $pc;
 
-
sleep(4);
 
-
}
 
-
print mean(@pa);
 
-
</pre>
 
-
 
-
 
-
chip-based more exact and smarter way:
 
-
--[[User:joerg_rw|joerg_rw]] 15:02, 16 October 2017 (UTC)
 
-
<pre>
 
-
IroN900:~# bq27k-detail2|grep -A1 0x23; sleep 60; bq27k-detail2|grep -A1 0x23
 
-
0x23 - 0x22:  3031  SAE Available Energy High - Low Byte            29.2  µV2h (2)  R
 
-
                    *29.2 / 20 =  4425 mWh
 
-
0x23 - 0x22:  3029  SAE Available Energy High - Low Byte            29.2  µV2h (2)  R
 
-
                    *29.2 / 20 =  4422 mWh
 
-
</pre>
 
-
(4425 mWh -  4422 mWh) / 1/60h = 180mW
 
-
 
-
<pre>
 
-
IroN900:~# bq27k-detail2|grep -A1 0x23; sleep 180; bq27k-detail2|grep -A1 0x23
 
-
0x23 - 0x22:  3022  SAE Available Energy High - Low Byte            29.2  µV2h (2)  R
 
-
                    *29.2 / 20 =  4412 mWh
 
-
0x23 - 0x22:  3019  SAE Available Energy High - Low Byte            29.2  µV2h (2)  R
 
-
                    *29.2 / 20 =  4407 mWh
 
-
</pre>
 
-
(4412 mWh - 4407 mWh ) * 3600 s/h / 180 s = 100mW
 
-
 
-
 
-
most accurate method: get average of NAC over a long period:
 
-
<pre>IroN900:~# bq27200.sh 300
 
-
LOOPMODE=300 RS=22
 
-
      mv  RSOC CSOC mA  NAC  CACD CACT TTF  TTE  TEMP
 
-
17:50 4115 96  96  -41  1098 1098 1098 65535 1606  25  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
17:55 4131 96  96  -13  1095 1095 1095 65535 4882  25  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:00 4131 96  96  -14  1094 1094 1094 65535 4496  24  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:05 4131 96  96  -22  1091 1091 1091 65535 2884  24  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:10 4123 95  95  -109 1087 1087 1087 65535 594  25  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:15 4118 95  95  -41  1084 1084 1084 65535 1572  25  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:20 4118 95  95  -23  1080 1080 1080 65535 1884  25  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:25 4110 94  94  -33  1077 1077 1077 65535 1906  24  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:30 4118 94  94  -34  1076 1076 1076 65535 1859  24  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:35 4107 94  94  -12  1073 1073 1073 65535 5156  24  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
18:40 4113 94  94  -143 1069 1069 1069 65535 447  25  NOACT:0 IMIN:0 CI:0 CALIP:0 VDQ:1 EDV1:0 EDVF:0
 
-
</pre>
 
-
average delta-NAC per 5 minutes: 3mAh = 36mAh/h
 
-
 
-
delta-NAC 17:50 4115 96 1098  -  18:20 4118 95 1080 = 18mAh/30min = 36mA
 
-
 
-
The noise observed in spot reading of "mA" and "TTE" values is from random system activity. It averages out just fine to match the 36mA from long term measure.
 
-
 
-
Above test been done on a locked/dimmed device on WLAN with working PSM, xchat active
 
==Software==
==Software==
Line 184: Line 96:
* [[Wifi power saving mode]]
* [[Wifi power saving mode]]
-
* http://hssl.cs.jhu.edu/~neal/woodchuck/blog/2011/09/22/Wireless_Transfers_are_Battery_Intensive/
+
 
[[Category:N900]]
[[Category:N900]]
[[Category:N900 Hardware]]
[[Category:N900 Hardware]]

Learn more about Contributing to the wiki.


Please note that all contributions to maemo.org wiki may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here.
You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see maemo.org wiki:Copyrights for details). Do not submit copyrighted work without permission!


Cancel | Editing help (opens in new window)