STM32F767 clock frequency configuration

[gsaru.1]

Hi everyone,

Using the STM32 -F767 board with freertos, and the CubeMX we are trying to change the clock speed via the clock configuration tab in order to lower the power consumption.

After changing the HCLK to the desired speed (32MHz) or any other speed, generating the code, and running the application, I can see that the variable SystemCoreClock is indeed changing from the default value of 16000000 to the desired clock speed after calling SystemClock_Config function.

But still, the power consumption is staying very high and is not suitable for the consumption we should get with a clock speed of 32MHz.

Any ideas on how to approach this issue?

Thanks!

[Tesla DeLorean]

Assume we know next to nothing about your clocks or your settings..

HSE or HSI ?

PLL used? Settings?

Show entire clock tree and usage

What can you do at 32 MHz that you can't at say 16 or 24 MHz ?

Is it sleeping in Idle Task? ie WFI loop

[gsaru.1]

Thanks for the reply,

The clock tree:

The number we are changing is marked in red.

The consumption is about 104 mA regardless of the clock speed, and the power consumption simulator shows that we should get around 12-20 mA.

And yes, it is sleeping in idle task and not connected to anything else(modem etc.)

[Tesla DeLorean]

Seems like an excessive amount of current​. You're powering something else here, or something else is wrong on the circuit.