2024-10-04 12:49 PM
Short story: the X-NUCLEO-LPM01A is displaying higher current in low power modes than expected by the STM32U083 datasheet and the numbers shown on the LCD of the STM32U083C-DK.
Set up:
I followed this post to connect the X-NUCLEO-LPM01A to the STM32U083C-DK. I removed the JP7/IVDD jumper from the STM32U083C-DK.
Connections:
STM32U083C-DK | X-NUCLEO-LPM01A |
left pin of JP7 (VDD_MCU) | CN14 pin 3 (VOUT (+)) |
CN13 pin 8 (GND) | CN14 pin 1 (GND) |
I set the X-NUCLEO-LPM01A to output 3.3V using the joystick.
I downloaded the sample package from: https://www.st.com/en/embedded-software/stm32cubeu0.html
I opened the project in IAR embedded workbench version 9.60.2 from STM32Cube_FW_U0_V1.1.0\Projects\STM32U083C-DK\Demonstration\Demo\EWARM.
I started a debug session from EWARM connected to the STM32U083C-DK thru the on-board USB-C port ST-LINK.
At the time of the measurements, a debug session was not active. Both boards were connected to the same USB hub.
Measurements:
When the demo code is running, the X-NUCLEO-LPM01A reports about 4.8 mA. When I navigate to ULP -> STDBY on the menu, the LCD goes blank for ~30s, the menu button is unresponsive and the X-NUCLEO-LPM01A reports about 1.36 µA.
When I select ULP -> STOP1, the X-NUCLEO-LPM01A reports about 136 µA but the STM32U083C-DK shows 3.3 µA on its LCD.
Here's the full list of modes and reported current.
Mode | STM32U083C-DK LCD | X-NUCLEO-LPM01A LCD |
STDBY | Blank | 1.370 µA |
SLEEP | 101 µA | 289 µA |
LP SLP | 62 µA | 203 µA |
STOP1 | 3.3 µA | 135 µA |
STOP2 | 825 nA | 120 µA |
Photos of setup and one power mode executing:
Questions:
Thank you for your help.
Steve
2024-10-08 03:56 AM - edited 2024-10-08 08:03 AM
Hello @stakata and welcome to the Community ,
1- Is not possible to use the reset button in STDBY mode, the RTC wakes up after 30s.
2- The displayed values are the typic values not the measured values.
Ideally, the measurements could be done using the "Examples\PWR\PWR_ModesSelection" with Nucleo board.
Please review the readme file related to the Demo application which mentioned for Ultra Low Power Demo:
"
Users can switch between ULP modes using the UP/DOWN joystick keys. RIGHT or SEL joystick key are used to select the ULP mode.
Once ULP mode is selected, the system will enter ULP mode for ~33 seconds when goes out from ULP mode.
If a user would like to exit from stop mode before the ~33 seconds, he could use the "SEL" joystick key (during ULP the "SEL" joystick key is switched to Push Button mode).
During ULP mode, the Glass LCD will display the typical power consumption (no embedded measurement).
After Wakeup from stop mode, user could switch to another demo module by pressing the LEFT joystick key for 5 seconds.
"