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Please note that OPP transactions may be prevented at all by manually configuring the governor in order to use a fixed OPP.
For more details please refer to [[Linux_and_interrupt_latency_(Axel)|this page]].
==Processor heating and lifetime==
Use of internal LDOs increases the power dissipation on processor side significantly. As a consequence, operating junction temperature increases as well. This fact has to be taken into consideration at system integration level, as it affects directly is strictly related to expected processor lifetime. For more details please refer to
<ref name="AN4724">Freescale Semiconductor, Inc., ''AN4724 i.MX 6Dual/6Quad Product Lifetime Usage Estimates''</ref>
and
<ref name="AN4725">Freescale Semiconductor, Inc., ''AN4725 i.MX 6Solo/6DualLite Product Lifetime Usage Estimates''</ref>.
==Measuring power consumption==
[[AxelEVB-Lite|AxelEVB]] integrates a chip (Texas Instruments INA226) that allows to measure the power consumption of the Axel SOM. Following are the instructions to perform basic measurements (tested with the Linux kernel released with [[Axel_Embedded_Linux_Kit_(XELK)|XELK 2.3.0]]).
SOM power consumption measurements are available to be read from userspace via <code>sysfs</code> entries. Following are the entries for:
* Voltage expressed in mV:
<pre>
root@axel-lite:~# cat /sys/class/hwmon/hwmon0/device/in0_input
5
root@axel-lite:~# cat /sys/class/hwmon/hwmon0/device/in1_input
3286
</pre>
* Current expressed in mA:
<pre>
root@axel-lite:~# cat /sys/class/hwmon/hwmon0/device/curr1_input
425
</pre>
* Power expressed in uW:
<pre>
root@axel-lite:~# cat /sys/class/hwmon/hwmon0/device/power1_input
1500000
</pre>
INA225 - referenced as U25 on AxelEVB - is very flexible. For more details about possible please refer to its data sheet (http://www.ti.com/product/INA226).
==Useful links==
*[[FAQs (Axel)]]
*[[Thermal management (Axel)]]
*[[Power consumption (AxelLite)]]
==References==
{{reflist}}
