Reduce Current consumption upto 3.8mA

[PratikMore]

Configured the controller stm32l151c8t6a to work in low power run mode ( UART peripheral running) but the current consumption is going upto 6.2mA. After disabling the uart peripheral the consumption decreases upto 4.2mA. In real situation we are going to use SPI,DAC,ADC and UART so in reality the consumption will not decrease but increase. So is there any way of decreasing the current consumption upto 3.8mA?

[KDJEM.1]

Hello @PratikMore and welcome to the community;

are the free pins configured as analog? Could you try to set all free pins as analog to optimize the power consumption.

I recommend you look at these FAQs and example may help you to optimize the power consumption.

• How to minimize the power consumption in low power mode: An example using NUCLEO-F401RE board
• Tips for using STM32 low-power modes
• PWR_LPRUN

I hope this help you.

Kaouthar

[Tesla DeLorean]

Look at what's attached to the pins, that's often where the current consumption is coming from, as the STM has to sink/source what the external circuit draws.

If going to RS232 level shifters, perhaps look at ones with a signal indicating external connectivity, and able to gate supply.

[MM..1]

You some miss. Real MCU current can be very low as you see  in table

and combined with STOP under 600nA.

[PratikMore]

Hello @KDJEM.1 ,

I have followed the steps provided in this link :

https://community.st.com/t5/stm32-mcus/how-to-minimize-the-power-consumption-in-low-power-mode-an/ta-p/49801

But for flash deep power down mode what HAL API should i use for stm32L1 series because this 

HAL_PWREx_EnableFlashPowerDown();

api is not available. 

[KDJEM.1]

Hello @PratikMore;

To minimize the power consumption in Stop mode with STM32F4 MCU, FLASH can be powered off before entering the Stop mode using the HAL_PWREx_EnableFlashPowerDown() function.

To get the lowest consumption in Stop mode with STM32L1 MCU, the internal Flash memory also enters low power mode. When the Flash memory is in power-down mode, an additional startup delay is incurred when waking up from Stop mode.

In your case, try to check the consumption, when all pins are set as analog and without used "HAL_PWREx_EnableFlashPowerDown()" function.

I recommend you to look to stm32l1xx_hal_pwr.c and stm32l1xx_hal_pwr_ex.c for HAL functions.

Thank you.

Kaouthar