Power consumption and boot time on OSD32MP1-BRK

[Stjepan Horvat]

Hi guys,
I have been doing some measuring on OSD32MP1-BRK on OpenSTLinux (OSD32MP1_BRK_OpenSTLinux_Trusted_RELEASE_V2.0.img).
The measuring has been done on RIGOL-DM3058, 200mA measuring range with 5v power supply.
The measuring has been done using microcontroller which would give power over a relay and wait for GPIO to trigger HIGH on Octavo. I created a simple systemd service which is started on entering the system.
Here is what i got (boot time have multiple measurements):

The system is powered off:
consumption: 1.33mA
boot time: 19776ms, 21480ms, 19771ms, 21521ms, 21421ms, 19718ms

Sleep mode group 1:
consumption: 16.3mA
boot time: 371ms, 370ms, 342ms

Sleep mode group 3:
consumption: 4.36mA
boot time: 1226ms, 1133ms, 1176ms

Is this something expected?
Is it possible to get lower consumption?
Thanks

[Neeraj Dantu]

Stjepan,

Your measurements look normal, except may be the power consumption when the system is powered off. It should be closer to 0mA as VIN only goes to the PMIC and nothing else on the board is powered.

You can optimize the boot time, please take a look at https://wiki.st.com/stm32mpu/wiki/How_to_optimize_the_boot_time.

Best,
Neeraj

[Stjepan Horvat]

Thanks for the response.
Is there a way to find out how to optimize the consumption in powered off state? What should be the wakeup source in powered off state?
Thanks

[Neeraj Dantu]

Stjepan,

There is no optimization to be done for shutdown as no software is running on STM32MP1. The wakeup source from this state would be the PMIC_PONKEYN.

You can add a power switch ahead of VIN to further reduce current consumption by setting the PMIC to power down state.

Best,
Neeraj

[Neeraj Dantu]

Stjepan,

In addition, please take a look at ST’s power consumption measurement app note here: https://www.st.com/resource/en/application_note/an5284-stm32mp1-series-system-power-consumption-stmicroelectronics.pdf. The reference board that they use to make measurements on has the same PMIC+STM32MP1+DDR configuration. The only difference being EV1 used in the app note has 1GB memory and BRK has 512MB.

Best,
Neeraj

[Stjepan Horvat]

Thanks.

[Stjepan Horvat]

Is it possible to get a low power consumption below 500uA using only the MCU and then wake up the MPU+RAM using some kind of business logic?
I know that NRF52840 which uses arm-m4f has power consumption in sleep mode around 20uA.
Do you have any suggestions?

[Neeraj Dantu]

Stjepan,

You can run the M4 and put the A7 in a low power state, but it will not be as low power as 500uA. Please take a look at https://wiki.st.com/stm32mpu/wiki/Power_overview and https://www.st.com/resource/en/application_note/an5109-stm32mp15x-lines-using-lowpower-modes-stmicroelectronics.pdf for more information on power states of each subsystem.

An additional note is that in some of the low power states, since the A7 will loose all information, it will re-initialize the MCU and rerun the application software for the microcontroller.

Best,
Neeraj

[Stjepan Horvat]

Is it possible to enter hibernation mode? I tried it out but it said that it was not compiled with the kernel?

• This reply was modified 2 years, 7 months ago by Stjepan Horvat.

[Neeraj Dantu]

Stjepan,

The power modes allowed are described in the app notes linked in my previous replies. An equivalent power mode would be LP-Stop mode.

Best,
Neeraj

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