ST X-NUCLEO-LPM01A - How to Adapt an STM32 L432 Nucleo-32;Nucleo-64; Nucleo-144 to Power the MCU from the Arduino; AREF Pin; How to Adapt an STM32 L432 Nucleo-32 to Power the MCU from the Arduino AREF Pin

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UM2243How to adapt an STM32L432 Nucleo-32/Nucleo-64/ Nucleo-144 to power the MCU from the
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15 How to adapt an STM32L432 Nucleo-32/Nucleo-64/
Nucleo-144 to power the MCU from the Arduino
AREF pin
15.1 How to adapt an STM32L432 Nucleo-32
to power the MCU from the Arduino AREF pin
This appendix provides an example to adapt an STM32L432 Nucleo-32 board to power the
MCU only from the Arduino AREF pin, instead of the Arduino 3.3
V pin. This adaptation
allows the isolation of the MCU supply from peripherals (ST-LINK) in order to measure only
the MCU power consumption.
This example refers to the NUCLEO-L432KC schematics (MB1180) available from the
www.st.com/stm32nucleo web page:
1. Remove jumper JP1: disconnect VDD from +3V3 power source
2. Open SB9: T_NRST reset MCU from ST-LINK
3. Open SB4 and SB17: MCO clock from ST-LINK to MCU (set HSI or use external crystal
as MCU clock reference)
4. Open SB2: STLINK_RX of Virtual COM port
5. Open SB3: STLINK_TX of Virtual COM port.
Note: SWCLK and SWDIO cannot be disconnected. STM32L432 software should set these two
signals (PA14 and PA13 respectively) to high impedance.
15.2 How to adapt an STM32L476 Nucleo-64
to power the MCU from the Arduino AREF pin
This appendix provides an example to adapt an STM32L476 Nucleo-64 board to power the
MCU from only the Arduino AREF pin, instead of the Arduino 3.3
V pin. This adaptation
allows the MCU supply to be isolated from peripherals (ST-LINK) in order to measure the
MCU power consumption only.
This example is refers to NUCLEO-L476RG schematics (MB1136) available from the
www.st.com/stm32nucleo web page:
1. Remove jumper JP6: disconnect VDD from +3V3 power source
2. Remove jumper JP5: +5V power source selection; to disconnect +5 V from E5V and
U5V
3. Open SB13: STLINK_RX of Virtual COM port
4. Open SB14: STLINK_TX of Virtual COM port
5. Open SB16: MCO clock from ST-LINK to MCU (set HSI or use external crystal as MCU
clock reference)
6. Remove jumper CN2_1-2: SWCLK from ST-LINK to MCU
7. Remove jumper CN2_3-4: SWDIO from ST-LINK to MCU
8. Open SB15: SWO from ST-LINK to MCU
9. Open SB12: NRST from ST-LINK to MCU.