What is voltage scaling feature ?

[RN_it]

Posted on May 18, 2018 at 09:20

Hello , 

I am using TIM6 to generate 1 sec of delay and i am toggling LED gpio in the timer ISR

HCLK is 50MHz , prescalar = 999, and period = 49999

The issue is when i use below macro, i get close to 1sec. shown in the pic below

__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);

and when the that macro is not used. there is a significant difference . I want to know how exactly that macro is affecting here. i can not able to connect the dots. please help 

without above macro output 

[Nesrine M_O]

Posted on May 18, 2018 at 10:39

Hi

balckiran

,

The voltage scaling allows optimizing the power consumption when the device is clocked below the maximum system frequency.

for more details please refer toPower controller (PWR) chapter , Voltage regulator paragraph in you reference manual and General operating conditions in your datasheet :

STM32F7 datasheet example:

-Nesrine-

[RN_it]

Posted on May 18, 2018 at 10:57

Very sorry , that doesnt answer my question . I want to know why i see difference in timing when scale 3 is used . Thank you .