STM32U575 Boot up power consumption

[Jet1]

Hi All, 

I am trying to reduce the boot up power consumption using STM32U575RIT6xQ . I using a 4-20mA power source and the boot up power is 7.6mA. After it boots up the power consumption is 3.4mA. 

We are using Free RTOS. Below is the pins that are activated :

1. ADC1      3 Channels

2. GPIO       26 Pins 

3. I2C2        2 pins 

4. TIM           2 timers

5. UART4     

6. USART3   Asynchronous 

My requirement is the device should boot up and run below 3.5mA. Is there a way to reduce it in the firmware at the boot up. 

I am aware that power saving mode can be implemented in the code but not sure how to reduce power at boot up. If anyone could provide any assistance it would be very helpful

Thank You in advance 

[Sarra.S]

Hello @Jet1, 

Referring to the dedicated reference manual, the power consumption in Run mode can be reduced by one of the following means: 

• Slowing down the system clocks and configuring voltage scaling to lower-power ranges.
• Gating the clocks to the APB and AHB peripherals when they are unused. 
• Powering off unused RAMs When a SRAM has been powered off, it can be powered on again by following the procedure:

1. Reset SRAMxPD in PWR_CR1
2. Wait for 1.6 µs
3. Set SRAMxEN in RCC_AHBxENR IS RUN MODE is boot up