STM32U0 Notes

• Datasheets
  • DS14581 STM32U031x4/6/8
  • DS14548 STM32U073x8/B/C
  • DS14463 STM32U083xC
• Application Notes
  • AN5938 Getting started with STM32U0 MCUs hardware development
  • AN2606 STM32 microcontroller system memory boot mode
• Reference Manual
  • RM0503 Reference manual

1. Nucleo-U083RC (STM32U083RCT6)
   • Purchasing
     • S$21.68 at element14
   • User Manuals
     • UM1727 Getting started with STM32 Nucleo board software development tools
     • UM3256 STM32 Nucleo-64 boards (MB1932)
2. STM32U083C-DK (STM32U083MC)
   • Purchasing
     • S$37.06 at element14
   • User Manuals
     • UM3292 Discovery kit with STM32U083MC MCU
     • UM3313 STM32CubeU0 STM32U083C-DK demonstration firmware

• VDDx
  • 1.71 ≤ VDDx ≤ 3.60 V (absolute maximum: 4.00 V)
  • Nucleo-083RC LEDs become very dim when 3.3V net falls below 1.80 V
• Brownout Reset¹⁾
  • Selectable: 1.7, 2.0, 2.2, 2.5 or 2.8 V

In order to use the native USB for programming on pins PA11 and PA12, the following settings must be done in STM32CubeProgrammer –> Option bytes –> User Configuration.

Option byte name	Value	Description	Notes
NBOOT_SEL	0 (Unchecked)	BOOT0 pin (legacy mode)	Factory setting is 1. You must change it to 0 to keep USB DFU programming capability.
nBOOT1	1 (Checked)	Boot from Flash if BOOT0 = 1, otherwise System Memory	This is the factory setting
NRST_MODE	1 or 3	1: Reset input only 3. Bidirectional reset: The NRST pin is configured in reset input/output (legacy) mode	3 is the factory setting

State	Peripherals	Memory	Voltage Supplies (VDDx)	STM32RTC::LSI_CLOCK	STM32RTC::LSE_CLOCK	STM32RTC::HSE_CLOCK
LowPower.idle()	On	On	On	Supported	Supported	Supported
LowPower.sleep()	On	On	On	Supported	Supported	Supported
LowPower.deepSleep()	On	On	On	Supported	Supported	Supported
LowPower.shutdown()	Off	Off	Off		Supported

: External hardware required

• External 32.768 kHz crystal for LSE²⁾

• rtc.setClockSource(STM32RTC::LSE_CLOCK);
  rtc.begin();