Make sure first of all that you have a part number ending in P in the STM32L on the Nucleo board: this will ensure that the STM32L supports external SMPS.
On the Nucleo board a SMPS has been populated and the idea is to measure the overall power consumption of the MCU with and without the use of SMPS.
Startting with the STM32CubeL4 Firmware Package V1.7.0, we provide the STM32 Nucleo PWR GUI tool allowing a quick assessment of STM32L4 low power performance.
The STM32 Nucleo Power GUI tool is readily available under Utilities/PC_Software/STM32Nucleo_Power_GUI
It connects to the STM32 Nucleo hardware boards supported by the firmware package and allows selecting the various low-power modes and benchmarking codes thanks to the available binary files.
To use "STM32 Nucleo Power GUI tool" :
- Connect the STM32 Nucleo board to a PC with a 'USB type A to Micro-B'
(Nucleo-144) or 'USB type A to Mini-B' (Nucleo-64) cable through USB
connector CN1 to power the board.
- Select the wanted binary available under “STM32Nucleo_Power_GUI/Binaries” and reprogram
(e.g. with STM32 ST-LINK Utility, available for download from www.st.com) the STM32 Nucleo firmware.
Once done, to ensure all IOs are at their reset levels, unplug then plug
the board again.
- Connect an amperemeter to the IDD jumper (JP5 for Nucleo-144, JP6 for Nucleo-64).
- Unzip "Nucleo GUI.zip" on your laptop or desktop and launch Qtserial.exe.
- Obey the instructions appearing on the screen in connecting to the COM port
associated with the Nucleo board.
- Pick one low power mode proposed among those by the GUI tool and press
- Measure the MCU power consumption on the amperemeter.
- Reset the board before picking up another low power mode.
Binaries available under " STM32Nucleo_Power_GUI/Binaries " folder are
- STM32L476RG_NUCLEO.hex for STM32L476RG Nucleo board
- STM32L496ZG_NUCLEO.hex for STM32L496ZG Nucleo board without external SMPS
- STM32L496ZG_NUCLEO_extSMPS.hex for STM32L496ZG Nucleo board with external SMPS
The GUI will permit to enter different low power modes and see the difference