7.1.3
Target voltage level on STM32CubeProgrammer
The target voltage level is shown on the STM32CubeProgrammer. On the B-L462E-CELL1 Discovery kit for IoT
nodes, the target (STM32L462RE on the module) voltage is 1.8 V.
Note:
To reduce the power consumption for low
‑
power measurement, the value of R62 and R55 sampling resistors is
raised from 4.7 kΩ to 1 MΩ. In this case, the target voltage can not be correctly measured by ST-LINK and may
be displayed as 1.6 V on STM32CubeProgrammer.
7.2
Power supply
The B-L462E-CELL1 Discovery kit for IoT nodes is designed to be powered by a 5 V DC power supply. It is
possible to configure the B-L462E-CELL1 Discovery kit for IoT nodes to use any of the following five sources
for the power supply: UartUsbVbus, Vbus, 5V_USB_CHG, 5V_USB_PWR, and EXT_BAT. Power sources are
automatically selected by diodes.
All extern power sources are connected to the JP1 jumper, so JP1 can be used to measure the current which is
consumed by the module.
•
UartUsbVbus is provided by the CN10 UART USB connector.
•
Vbus is provided by the CN8 user USB connector.
•
5V_USB_CHG is provided by the CN9 ST-LINK/V2-1 USB connector. This power source can be controlled
by the onboard ST-LINK/V2-1.
•
5V_USB_PWR is provided by the CN11 power USB connector.
•
EXT_BAT is connected to a battery case that contains three AAA batteries. As it can only provide a 4.5 V
power source, this power source is not designed for long-time and huge-current applications. Low-power
applications can consider using this as the main power source and other applications may use this as the
back-up power source.
UM2743
Power supply
UM2743
-
Rev 1
page 14/58
