STMicroelectronics NUCLEO-G431KB User Manual

UM2397

User manual

STM32G4 Nucleo-32 board (MB1430)

Introduction

The STM32G4 Nucleo-32 board (NUCLEO-G431KB) provides an affordable and flexible way for users to try out new concepts
and build prototypes, by choosing from the various combinations of performance, power consumption and features provided by

the STM32G4 Series microcontroller. The Arduino™ Nano V3 connectivity provides easy means of expanding the functionality of
the Nucleo open development platform with a wide choice of specialized shields. The STM32G4 Nucleo-32 board does not
require any separate probe as it integrates the STLINK-V3E debugger/programmer. The STM32G4 Nucleo-32 board comes
with the comprehensive free software libraries and examples available with the STM32CubeG4 MCU Package.

Figure 1. NUCLEO-G431KB top view

Figure 2. NUCLEO-G431KB bottom view

Pictures are not contractual.

UM2397 - Rev 1 - May 2019
For further information contact your local STMicroelectronics sales office.

www.st.com

1 Features

• STM32G4 microcontroller (Arm® Cortex®-M4 at 170 MHz) in UFQFPN32 package, featuring 128 Kbytes of
Flash memory and 32 Kbytes of SRAM for STM32G431KBT6

• 1 user LED

• 1 RESET push button

• 24 MHz HSE crystal oscillator

• Board connectors:

– USB with Micro-B

– Arduino Nano V3 expansion connector

• Flexible power-supply options: ST-LINK USB V

• On-board STLINK-V3E debugger/programmer with SWD connector:

– USB re-enumeration capability: virtual COM port, mass storage, debug port

• Comprehensive free software libraries and examples available with the STM32Cube package

Note: Arm is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.

or external sources

BUS

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Features

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2 Ordering information

2.1 Products

To order the STM32G4 Nucleo-32 board, refer to Table 1.

Order code Reference board Target STM32

NUCLEO-G431KB MB1430 STM32G431KBT6U

2.2 Product marking

Evaluation tools marked as “ES” or “E” are not yet qualified and therefore not ready to be used as reference
design or in production. Any consequences deriving from such usage will not be at ST charge. In no event, ST will
be liable for any customer usage of these engineering sample tools as reference design or in production.

“E” or “ES” marking examples of location:

• On the targeted STM32 that is soldered on the board (for illustration of STM32 marking, refer to the STM32
datasheet “Package information” paragraph at the www.st.com website).

• Next to the evaluation tool ordering part number that is stuck or silk-screen printed on the board.

This board features a specific STM32 device version, which allows the operation of any bundled commercial
stack/library available. This STM32 device shows a "U" marking option at the end of the standard part number
and is not available for sales.

In order to use the same commercial stack in his application, a developer may need to purchase a part number
specific to this stack/library. The price of those part numbers includes the stack/library royalties.

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Ordering information

Table 1. List of available products

2.3 Codification

The meaning of the codification is explained in Table 2.

NUCLEO-XXYYKT Description Example: NUCLEO-G431KB

XX MCU series in STM32 Arm Cortex MCUs STM32G4 Series

YY MCU product line in the series STM32G431

K STM32 package pin count 32 pins

B

Table 2. Codification explanation

STM32 Flash memory size:

• B for 128 Kbytes

128 Kbytes

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3 Development environment

3.1 System requirements

• Windows® OS (7, 8 and 10), Linux® 64-bit, or macOS

• USB Type-A to Micro-B cable

Note:

macOS® is a trademark of Apple Inc. registered in the U.S. and other countries.

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Development environment

®

3.2

Note:

Development toolchains

• Keil® MDK-ARM (see note)

• IAR™ EWARM (see note)

• GCC-based IDEs

On Windows® only.

3.3 Demonstration software

The demonstration software, included in the STM32Cube MCU Package corresponding to the on-board
microcontroller, is preloaded in the STM32 Flash memory for easy demonstration of the device peripherals in
standalone mode. The latest versions of the demonstration source code and associated documentation can be
downloaded from www.st.com.

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4 Conventions

Table 3 provides the conventions used for the ON and OFF settings in the present document.

Convention Definition

Jumper JPx ON Jumper fitted

Jumper JPx OFF Jumper not fitted

Jumper JPx [1-2] Jumper should be fitted between Pin 1 and Pin 2

Solder bridge SBx ON SBx connections closed by 0 Ω resistor

Solder bridge SBx OFF SBx connections left open

Resistor Rx ON Resistor soldered

Resistor Rx OFF Resistor not soldered

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Conventions

Table 3. ON/OFF convention

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5 Quick start

The STM32G4 Nucleo-32 board is a low-cost and easy-to-use development kit, used to evaluate and start a
development quickly with an STM32G4 Series microcontroller in LFQFPN 32-pin package. Before installing and
using the product, accept the Evaluation Product License Agreement from the www.st.com/epla webpage. For
more information on the STM32G4 Nucleo-32 and for demonstration software, visit the www.st.com/stm32nucleo
webpage.

5.1 Getting started

Follow the sequence below to configure the STM32G4 Nucleo-32 board and launch the demonstration application
(refer to Figure 4 for component location):

1. Check the jumper position on the board (refer to Table 4).

2. For the correct identification of the device interfaces from the host PC and before connecting the board,
install the Nucleo USB driver available on the www.st.com/stm32nucleo website.

3. To power the board, connect the STM32G4 Nucleo-32 board to a PC with a USB cable (Type-A to Micro-B)
through the USB connector CN1 of the board.

4. Then, LED LD1 (COM) and green LED LD4 (5V_PWR) light up, green LED LD2 blinks.

5. Remove the jumper placed between D2 (CN4 pin 5) and GND (CN4 pin 4).

6. Observe how the blinking of the green LED LD2 changes, when the jumper is in place or removed.

7. Download the software demonstration software and several software examples that help to use the STM32
Nucleo features. These are available on the NUCLEO-G431KB webpage

8. Develop your own application using the available examples

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Quick start

Table 4. Jumper configuration

Jumper Definition Position(1) Comment(1)

JP1 IDD ON

1. Default jumper state is in bold.

For STM32G4 current
measurements

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6 Hardware layout and configuration

The STM32G4 Nucleo-32 board is designed around the STM32 microcontrollers in a 32-pin UFQFPN package.

Figure 3 shows the connections between the STM32 and its peripherals (STLINK-V3E, push button, LEDs, USB

and Arduino Nano). Figure 4 and Figure 5 show the location of these features on the STM32G4 Nucleo-32 board.
The mechanical dimensions of the board are shown in Figure 6.

Figure 3. Hardware block diagram

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Hardware layout and configuration

Bicolor

LED
LD1

(COM)

25 MHz

Crystal

USB

Micro-B

connector

(CN1)

STLINK-V3E

SWD

STLK
MCO

SWD

STM32G431KB

STLINK-V3E Part

Embedded

VCP

UART

VCP

UART

GPIOGPIO

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XXX

GPIO

ARDUINO NANO

Red LED

LD3 (OC)

IDD

Connector
or jumper

GPIOs

OSC

ARDUINO NANO

24 MHz

Crystal

Green LED

LD2 (USER)

Green LED

LD4

(5V_PWR)

B1

button

RESET

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6.1 PCB layout

LD1 bicolor LED (COM)

X1 25 MHz oscillator

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PCB layout

Figure 4. Top layout

CN1

STLINK-V3E Micro-B
USB connector

CN2

SWD connector (not fitted)

U1 Main CPU
(STM32G431KBT6)

X2 24 MHz HSE crystal

LD3 red LED (Overcurrent)

LD2 green LED (USER)

LD4 green LED (5V_PWR)

B1 green RESET button

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U5 STM32F723IEK6

(STLINK-V3E MCU)

CN3

Arduino Nano connector

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PCB layout

Figure 5. Bottom layout

CN1

STLINK-V3E Micro-B
USB connector

U4 Common mode
filter with ESD
protection for USB

HW1 (2.54 mm
jumper) on CN4 [4-5]

U6 3V3_STLK regulator
LD3985M33R

U8 5V_VIN regulator
LD1117S50TR

U9 3V3 regulator
LD39050PU33R

U7

5V_USB_STLK regulator
STMPS2151STR

CN4

Arduino Nano connector

JP1 (1.27 mm jumper) for
IDD measurement

HW2 (1.27 mm jumper)
fitted on JP1 [1-2]

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6.2 Mechanical drawing

Figure 6. STM32G4 Nucleo 32 board mechanical drawing (in millimeter)

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Mechanical drawing

18.542 mm

50.292 mm

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6.3 Embedded STLINK-V3E

The way to program and debug the onboard STM32 MCU is by using the embedded STLINK-V3E.

The STM32G4 Nucleo-32 integrates the STLINK-V3E programming and debugging tool.

The embedded STLINK-V3E supports only SWD and VCP for STM32 devices. For information about debugging
and programming features, refer to the STLINK-V3SET debugger/programmer for STM8 and STM32 user manual
(UM2448), which describes in details all the STLINK-V3E features.

Features supported on STLINK-V3E:

• 5V power supplied by USB connector (CN1)

• USB 2.0 high-speed-compatible interface

• Serial wire debugging (SWD) specific features:

– 3 V to 3.6 V application voltage on the SWD interface and 5 V tolerant inputs

– Serial viewer (SWV) communication

• Status LD1 LED (COM), blinking during communication with the PC

• Fault red LED LD3 (OC), alerting on USB overcurrent request

• 5 V / 300 mA output power supply capability (U4), with current limitation and LED

• 5 V power green LED LD4 (5V_PWR)

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Embedded STLINK-V3E

6.3.1 Drivers

Before connecting the STM32G4 Nucleo-32 board to a Windows PC via USB, the user must install a driver for the
STLINK-V3E (not required for Windows 10). It is available at the www.st.com website.

In case the STM32G4 Nucleo-32 board is connected to the PC before the driver is installed, some STM32G4
Nucleo-32 interfaces may be declared as “Unknown” in the PC device manager. In this case, the user must install
the dedicated driver files, and update the driver of the connected device from the device manager as shown in

Figure 7.

Note: Prefer using the USB Composite Device handle for a full recovery.

Figure 7. USB composite device

Note: 37xx:

• 374E for STLINK-V3E without bridges functions

• 374F for STLINK-V3E with bridges functions

6.3.2 STLINK-V3E firmware upgrade

The STLINK-V3E embeds a firmware upgrade mechanism for in-situ upgrade through the USB port. As the
firmware may evolve during the lifetime of the STLINK-V3E product (for example new functionalities, bug fixes,
support for new microcontroller families), it is recommended to visit the www.st.com website before starting to use
the STM32G4 Nucleo-32 board and periodically, to stay up-to-date with the latest firmware version.

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6.4 Power supply

CN4

1

CN3

1

1515

Five different sources can provide the power supply:

• A host PC connected to CN1 through a USB cable (default setting)

• An external 5 V USB charger (5V_USB_CHGR) connected to CN1

• An external 7 V - 12 V (VIN) power supply connected to CN3 pin 1

• An external 3.3 V power supply (3V3) connected to CN3 pin 14

• An external 5 V power supply (5V) connected to CN3 pin 4

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Power supply

Figure 8. STM32G4 Nucleo-32 board power tree

5V_VIN

5V_USB_CHGR

5V_VIN

U7

Power switch 5V/0.5A

STMPS2151STR

U8

LDO

LD1117S50TR

U6

LDO

LD3985M33R

VIN

3V3_STLK

5V_USB_CHGR

5V_VIN

5V

3V3

AVDD

5V

3V3

STLINK-V3E USB connector (CN1)

Arduino Nano
Connector

DFU connector (CN2)

STM32F723IEK

(STLINK-V3E)

and

bicolor LED LD1 (COM)

5V_USB_STLK

5V_VIN

5V

U9

LDO

LD39050PU33R

VDD

AVDD

3V3

SB5 (ON)

JP1

ON

VDD

(VDD)

MCU STM32G4

(AVDD)

In case VIN, 5V or 3V3 is used to power the STM32G4 Nucleo-32 board, this power source must comply with the
EN-60950-1: 2006+A11/2009 standard and must be Safety Extra Low Voltage (SELV) with limited power
capability.

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If the power supply is 3V3 or 5V, the ST-LINK is not powered and cannot be used.

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Power supply

1) Power supply input from STLINK-V3E USB connector (default setting)

The STM32G4 Nucleo-32 board and shield can be powered from STLINK-V3E connector CN1 (5 V).

If the USB enumeration succeeds, the 5V_USB_STLK power is enabled, by asserting the T_PWR_EN signal from
STM32F723IEK6 "STLINK V3" (U5). This pin is connected to a power switch STMPS2151STR (U7), which
powers the board. The power switch STMPS2151STR (U7) features also a current limitation to protect the PC in
case of short-circuit on board. If an overcurrent (more than 500 mA) happens on board, the red LED LD3 (OC as
Over Current) is lit.

The Nucleo board and its shield can be powered from ST-LINK USB connector CN1, but only ST-LINK circuit gets
power before USB enumeration, because the host PC only provides 100 mA to the board at that time.

During the USB enumeration, the Nucleo board requires 500 mA power from the host PC.

• If the host is able to provide the required power, the enumeration finishes by a SetConfiguration command.
Then, the power switch STMPS2151STR is switched ON, the green LED LD4 (5V_PWR) is turned ON, thus
Nucleo board and its shield on it can consume 500 mA at the maximum.

• If the host is not able to provide the requested current, the enumeration fails. Therefore, the
STMPS2151STR power switch (U7) remains OFF and the MCU part including the extension board is not
powered. Therefore, the green LED LD4 remains turned OFF. In this case, it is mandatory to use an external
power supply.

Caution: If the maximum current consumption of the STM32G4 Nucleo-32 board and its shield boards exceeds 300 mA, it

is either mandatory to check the root cause of the overconsumption, and consequently (if needed) to power the
STM32G4 Nucleo-32 board with an external power supply connected to VIN, 5V or 3V3.

2) External power supply input from USB charger (5 V)

In case a USB charger powers the board, there is no USB enumeration. The target is powered anyway.

3) External power supply input from VIN (7 V - 12 V, 800 mA max)

The STM32G4 Nucleo-32 board and its shield boards can be powered in three different ways from an external
power supply, depending on the voltage used. The three cases are summarized in Table 5.

Table 5. External power sources: VIN (7 V - 12 V)

Input power

name

VIN CN3 pin 1 7 V to 12 V 800 mA

Connector

pins

Voltage range

Maximum

current

Limitation

From 7 V to 12 V only and input current capability is
linked to input voltage:

• 800 mA input current when VIN = 7 V

• 450 mA input current when 7 V < VIN < 9 V

• 250 mA input current when 9 V < VIN < 12 V

4) External power supply input from external 3.3 V

When a shield board provides the 3.3 V, it is interesting to use the 3V3 (CN3 pin 14) directly as power input (refer
to Table 4). In this case, the programming and debugging features are not available, since the ST-LINK is not
powered.

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Table 6. External power sources: 3V3

Input power name

3V3 CN3 pin 14 3 V to 3.6 V 1.3 A

Connector pins Voltage range Maximum current

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5) External power supply input from external 5 V

When a shield board provides the 5 V, it is interesting to use the 5V (CN3 pin 4) directly as power input (refer to

Table 7). In this case, the programming and debugging features are not available, since the ST-LINK is not

powered.

Table 7. External power sources: 5V

Input power name Connector pins Voltage range Maximum current

5V CN3 pin 4 4.75 V to 5.25 V 500 mA

6.4.1 Debugging while using VIN or EXT as an external power supply

When powered by VIN or 5V, it is still possible to use the ST-LINK for programming or debugging only, but it is
mandatory to power the board first using VIN or EXT (either 3V3 or 5V), then to connect the USB cable to the PC.
By acting this way, the enumeration succeeds, thanks to the external power source.

The user must respect the following power-sequence procedure:

1. Connect the external power source to VIN or 5V

2. Power on the external power supply 7 V< VIN < 12 V for VIN, or 5 V for 5V

3. Check that the green LED LD4 (5V_PWR) is turned ON

4. Connect the PC to the USB connector CN1

If this order is not respected, the board may be powered by USB first, then by VIN or 5V as the following risks
may occur:

1. If the board needs more than 300 mA current, the PC may be damaged or can limit the current supplied.
Consequently, the board is not powered correctly.

2. Enumeration requests 300 mA, so there is risk that the request is rejected and the enumeration does not
succeed if the PC cannot provide such current. Consequently, the board is not power supplied (LED LD3
remains OFF).

3V3 power supply

Using the 3V3 (CN3 pin 14) directly as power input, can be interesting, for instance, in case a shield provides the

3.3 V. In this case the STLINK-V3E is not powered, thus programming and debugging features are not available.

5V power supply

Using the 5V (CN3 pin 4) directly as power input, can be interesting, for instance, in case a shield provides the
5 V. In this case the STLINK-V3E is not powered, thus programming and debugging features are not available.

External power supply output

When powered by USB or VIN, the 5V (CN3 pin 4) can be used as output power supply for an Arduino Nano
shield. In this case, the user must respect the maximum current of the power source specified in “External power
sources” table.

The 3V3 (CN3 pin 14) can be used also as power supply output. The maximum current capability of the
LD39050PU33R regulator U9 (500 mA max) limits the available current.

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Clock sources

6.5

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Clock sources

There are four ways to configure the high-speed clock to use.

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Board functions

Figure 9. STM32G431KB Nucleo-32 board clock configuration

• HSI configuration (default): In that case, no external clock is used. The clock is coming from the
STLM32G4 microcontroller. The configuration is:

– SB9 and SB10 OFF

– SB11 and SB8 OFF

– SB13 OFF

• HSE bypass configuration (from ST-LINK): The input clock is the ST-LINK MCO output. The frequency is
fixed to 25 MHz, and connected to the PF0-OSC_IN of the STM32G4 microcontroller. The configuration
must be:

– SB9 and SB10 OFF

– SB11 and SB8 OFF

– SB13 ON

• HSE bypass configuration (from Arduino D7): The clock is coming from an external oscillator through the
pin PF0 (Arduino D7 pin 10 of the CN4 connector). The configuration must be:

– SB9 and SB10 OFF

– SB11 OFF and SB8 ON

– SB13 OFF

• HSE oscillator configuration: The clock is provided by an external crystal (X2) available in the PCB. The
X2 crystal has the following characteristics: 24 MHz, 6 pF load capacitance, 20 ppm. The recommendation is
to use NX2016SA-24MHz-EXS00A-CS10820 manufactured by NDK. For typical frequencies and its
capacitors and resistors, refer to the STM32 microcontroller datasheet and to the Oscillator design guide for
STM8S, STM8A and STM32 microcontrollers Application note (AN2867) for the oscillator design guide. The
configuration must be:

– SB9 and SB10 ON

– SB11 and SB8 OFF

– SB13 OFF

6.6

Board functions

6.6.1 LEDs

LD1 STLINK-V3 COM LED

The bicolor LED LD1 (green, red) provides information about STLINK-V3E communication status. LD1 default
color is red. LD1 turns to green to indicate that communication is in progress between the PC and the STLINK­V3E, with the following setup:

• Blinking red: the first USB enumeration with the PC is taking place

• Red LED ON: when the initialization between the PC and STLINK-V3E is complete

• Blinking red or green: during programming and debugging with target

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• Orange ON: communication failure

LD2 USER

This green LED is connected to the following STM32G4 I/O:

• PB8, if the configuration is SB7 ON, and SB6 OFF (default configuration)

• PB3, if the configuration is SB7 OFF, and SB6 ON

It is also connected to the Arduino D13 signal.

To light this LED, a high-logic state “1” must be written in the corresponding GPIO PB8 or PB3. A transistor drives
the LED, so its consumption does not affect the VDD STM32G4 power measurement.

LD4 5V_PWR

The green LED indicates that the STM32G4 part is powered, and the 5 V power is available on CN3 pin 4.

LD3 USB power fault (OC, overcurrent)

LD3 indicates that the board power consumption on USB ST-LINK exceeds 500 mA. Therefore, the user must
check the root cause of the overconsumption, and consequently (if needed) power the STM32G4 Nucleo-32
board with an external power supply.

6.6.2 Push button

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Solder bridges

B1 RESET (button)

This push button is connected to NRST (PG10-NRST) and is used to reset the STM32G4 microcontroller.

6.6.3 Current consumption measurement (IDD)

Jumper JP1, labeled IDD, is used to measure the STM32G4 microcontroller consumption by removing the jumper
and by connecting an ammeter.

• JP1 ON: STM32G4 is powered by 3V3 voltage (default)

• JP1 OFF: an ammeter must be connected to measure the STM32G4 current. If there is no ammeter, the
STM32G4 is not powered.

6.6.4 Virtual COM port (VCP): USART

The STM32G4 Nucleo-32 board offers the possibility to connect a USART interface to the STLINK-V3E.

Table 8. USART2 connection

Solder bridge configuration

SB1, SB12: ON USART2 (PA2/PA3) connected to STLINK-V3E Virtual COM port.

1. The default configuration is in bold

(1)

The communication between the target and the MCU is enabled on USART2 to support the Virtual COM port.

6.7 Solder bridges

All the 16 solder bridges are located on the bottom layer of the STM32G4 Nucleo-32 board.

Feature

(1)

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Solder bridge control

T_VCP_TX SB1

Table 9. Solder bridge configuration

Solder

bridge (SB)

(1)

State

ON T_VCP_TX is connected to STM32G4 I/O PA2.

OFF T_VCP_TX is not connected to STM32G4 I/O PA2.

Description

(1)

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Solder bridges

Solder bridge control

Solder

bridge (SB)

T_VCP_RX SB12

3.3 LDO output SB15

SMD ferrite bead L1 SB5

LD2

AGND SB16

ARD_A2 SB14

T_SWO on PB3 SB4

SB7

SB6

SB3

SB2

State

(1)

Description

(1)

ON T_VCP_RX is connected to STM32G4 I/O PA3.

OFF T_VCP_RX is not connected to STM32G4 I/O PA3.

ON U9 LDO output provides 3.3V.

OFF

ON

U9 LDO does NOT provide 3.3V. The user must connect an
external 3.3V source.

SMD ferrite bead L1 shunted. VDDA connected on VDD
voltage supply

OFF SMD ferrite bead L1 on STM32G4 VDDA voltage supply

ON

OFF

ON

OFF

The green user LED LD2 is connected to STM32G4 I/O
PB8 (SB7 ON, and SB6 OFF).

The green user LED LD2 is connected to STM32G4 I/O PB3
(SB7 OFF, and SB6 ON).

The green user LED LD2 is connected to STM32G4 I/O PB3
(SB6 ON, and SB7 OFF).

The green user LED LD2 is connected to STM32G4 I/O
PB8 (SB6 OFF, and SB7 ON).

ON AGND connected to GND. Reserved, do not modify.

OFF AGND not connected to GND.

STM32 PA15 is connected to CN3 pin 7 for I2C SCL

ON

support on Arduino Nano A5. In such a case, STM32 PA15
does not support Arduino Nano D5 and PA6 must be
configured as floating input.

OFF

CN3 pin 7 is used as Arduino Nano analog input A5 without
I2C support and CN4 pin 8 is available as Arduino Nano D5.

STM32 PB7 is connected to CN3 pin 8 for I2C SDA

ON

support on Arduino Nano A4. In such a case, STM32 PB7
does not support Arduino Nano D4 and PA5 must be
configured as floating input.

OFF

ON

OFF

CN3 pin 8 is used as Arduino Nano analog input A4 without
I2C support and CN4 pin 7 is available as Arduino Nano D4.

Arduino Nano A2 (CN3, pin 10) is connected to STM32G4 I/O
PA3.

Arduino Nano A2 (CN3, pin 10) is disconnected to
STM32G4 I/O PA3.

ON T_SWO connected to PB3.

OFF T_SWO not connected to PB3.

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Solder bridges

Solder bridge control

HSE CLK selection

1. The default SB state is in bold.

Solder

bridge (SB)

SB9

and

SB10

SB11

SB8

SB13

State

(1)

Description

(1)

ON HSE provided by external 24 MHz XTAL CLK X2

OFF HSE not provided by external 24 MHz XTAL CLK X2

ON

OFF

ON

OFF

PF1-OSC_OUT pin connected to PF1 (Arduino Nano, CN4,
pin 11)

PF1-OSC_OUT pin not connected to PF1 (Arduino Nano,
CN4, pin 11)

PF0-OSC_IN pin connected to PF0 (Arduino Nano, CN4, pin

10)

PF0-OSC_IN pin not connected to PF0 (Arduino Nano,
CN4, pin 10)

ON PF0-OSC_IN provided by 25 MHz ST-LINK MCO

OFF PF0-OSC_IN not provided by 25 MHz ST-LINK MCO

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7 Board connectors

Several connectors are present on the STM32G4 Nucleo-32 board.

7.1 STLINK-V3E USB Micro-B connector CN1

The USB socket CN1 connects the embedded STLINK-V3E to the PC for the programming and debugging
purposes.

Figure 10. USB Micro-B connector CN1 (front view)

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Board connectors

Table 10. USB Micro-B connector CN1 pinout

Connector

CN1

Pin

number

1 VBUS 5V_USB_CHGR - 5 V power

2 DM USB_DEV_HS_CN_N R14 USB diff pair N

3 DP USB_DEV_HS_CN_P R15 USB diff pair P

4 ID - - -

5 GND - - GND

Pin

name

7.2 Arduino Nano V3 connectors

The Arduino connectors CN3 and CN4 are male connectors compatible with the Arduino standard. Most shields
designed for Arduino can fit with the STM32G4 Nucleo-32 board.

The Arduino connectors on the STM32G4 Nucleo-32 board support the Arduino Nano V3.

Signal name

STLINK-V3E MCU

pin

Function

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Figure 11. Arduino connectors

UM2397

Arduino Nano V3 connectors

CN3

Arduino Nano connector

CN4

Arduino Nano connector

UM2397 - Rev 1

The related pinout for Arduino connector appears in Figure 12 and is listed in Table 11.

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Figure 12. Arduino connector pinout

UM2397

Arduino Nano V3 connectors

UM2397 - Rev 1

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Table 11. Arduino connector pinout

UM2397

Arduino Nano V3 connectors

Connector

Pin

number

Pin name Signal name

STLINK-V3E MCU

pin

Function

1 VIN VIN - Power input

2 GND GND - Ground

3 T_NRST T_NRST PG10_NRST RESET

4 5V 5V - 5V input/output

5 A7 ARD_A7 PA2 ADC1_IN3

6 A6 ARD_A6 PA7 ADC2_IN4

CN3

7

8

A5

A4

(1)

(1)

ARD_A5

ARD_A4

PA6

PA15

PA5

PB7

ADC2_IN3

I2C1_SCL

ADC2_IN13

I2C1_SDA

9 A3 ARD_A3 PA4 ADC2_IN17

10 A2 ARD_A2 PA3 ADC1_IN4

11 A1 ARD_A1 PA1 ADC2_IN2

12 A0 ARD_A0 PA0 ADC2_IN1

13 AVDD AVDD - AVDD

14 3V3 3V3 - 3V3 input/output

15 D13 ARD_D13 PB3 SPI1_CLK

1

D1 ARD_D1 PA9

2 D0 ARD_D0 PA10

USART1_TX

USART1_RX

(2)

(2)

3 T_NRST T_NRST PG10_NRST RESET

4 GND - - 3V3 input/output

5 D2 ARD_D2 PA12 -

6 D3 ARD_D3 PB0 PWM: TIM3_CH3

D4

D5

(1)

(1)

ARD_D4 PB7 TIM4_CH2 / I2C1_SDA

ARD_D5 PA15 TIM2_CH1 / I2C1_SCL

CN4

7

8

9 D6 ARD_D6 PB6 PWM: TIM1_CH1

10

11

D7

D8

(3)

(3)

ARD_D7 PF0 -

ARD_D8 PF1 -

12 D9 ARD_D9 PA8 PWM: TIM4_CH1

13 D10 ARD_D10 PA11

SPI1_CS

(4)

/ TIM1_CH4

14 D11 ARD_D11 PB5 SPI1_MOSI / TIM3_CH2

1.

Limitations on A4 and A5, related to I2C configuration, are explained in Table 9. Solder bridge configuration according to

15 D12 ARD_D12 PB4 SPI1_MISO

SB2/SB3 setting.

2. Only one USART is available and shared between Arduino Nano and VCP. The selection is done by remapping (no need to

change the hardware configuration).

3. D7/D8 are shared with OSC_IN/OSC_OUT.

4. SPI_CS is handled by GPIO.

UM2397 - Rev 1

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8 STM32G4 Nucleo-32 I/O assignment

Table 12. Nucleo-32 I/O assignment

Pin Pin name Signal or label

1 VDD VDD VDD voltage supply

2 PF0-OSC_IN PF0-OSC_IN HSE CLK input / IO

3 PF1-OSC_OUT PF1-OSC_OUT HSE CLK output / IO

4 PG10-NRST T_NRST RESET

5 PA0 PA0 Analog input - ARD_A0: ADC2_IN1

6 PA1 PA1 Analog input - ARD_A1: ADC2_IN2

7 PA2 T_VCP_TX USART2_Tx - T_VCP_TX

8 PA3 T_VCP_RX USART2_Rx - T_VCP_RX / ARD_A2: ADC1_IN4

9 PA4 PA4 Analog input -ARD_A3: DC2_IN17

10 PA5 PA5 Analog input - ARD_A4: DC2_IN13

11 PA6 PA6 Analog input - ARD_A5: DC2_IN3

12 PA7 PA7 Analog input - ARD_A6: DC2_IN4

13 PB0 PB0 ARD_D3 - PWM: TIM3_CH3

14 VSSA VSSA Analog Ground

15 VDDA VDDA Analog voltage supply

16 VSS VSS Ground

17 VDD VDD VDD voltage supply

18 PA8 PA8 ARD_D9: PWM: TIM1_CH1

19 PA9 PA9 ARD_D1: USART1_TX

20 PA10 PA10 ARD_D0: USART1_RX

21 PA11 PA11 ARD_D10: SPI1_CS / TIM1_CH4

22 PA12 PA12 ARD_D2: IO

23 PA13 PA13 T_SWDIO

24 PA14 PA14 T_SWCLK

25 PA15 PA15 ARD_D5: TIM2_CH1 / I2C1_SCL

26 PB3 PB3 ARD_D13: SPI1_CLK

27 PB4 PB4 ARD_D12: SPI1_MISO

28 PB5 PB5 ARD_D11: SPI1_MOSI / TIM3_CH2

29 PB6 PB6 ARD_D6: PWM: TIM4_CH1

30 PB7 PB7 ARD_D4: TIM4_CH2 / I2C1_SDA

31 PB8-BOOT0 PB8-BOOT0 BOOT

32 VSS VSS Ground

1. The default configuration is in bold.

STM32G4 Nucleo-32 I/O assignment

Main feature / optional feature / (SB)

UM2397

(1)

UM2397 - Rev 1

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UM2397

Federal Communications Commission (FCC) and Industry Canada (IC) Compliance Statements

9 Federal Communications Commission (FCC) and Industry Canada

(IC) Compliance Statements

9.1 FCC Compliance Statement

Part 15.19

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) this
device may not cause harmful interference, and (2) this device must accept any interference received, including
interference that may cause undesired operation.

Part 15.21

Any changes or modifications to this equipment not expressly approved by STMicroelectronics may cause
harmful interference and void the user's authority to operate this equipment.

Part 15.105

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part
15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates uses and can radiate radio frequency energy and, if not installed
and used in accordance with the instruction, may cause harmful interference to radio communications. However,
there is no guarantee that interference will not occur in a particular installation. If this equipment does cause
harmful interference to radio or television reception which can be determined by turning the equipment off and on,
the user is encouraged to try to correct interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and receiver.

• Connect the equipment into an outlet on circuit different from that to which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

Note: Use only shielded cables.

9.2

Responsible party (in the USA)

Terry Blanchard
Americas Region Legal | Group Vice President and Regional Legal Counsel, The Americas
STMicroelectronics, Inc.
750 Canyon Drive | Suite 300 | Coppell, Texas 75019
USA
Telephone: [phone]

IC Compliance Statement

Industry Canada ICES-003 Compliance Label: CAN ICES-3 (B) / NMB-3 (B).

UM2397 - Rev 1

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Revision history

UM2397

Table 13. Document revision history

Date Version Changes

17-May-2019 1 Initial release.

UM2397 - Rev 1

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UM2397

Contents

Contents

1 Features...........................................................................2

2 Ordering information ..............................................................3

2.1 Products ......................................................................3

2.2 Product marking ...............................................................3

2.3 Codification ...................................................................3

3 Development environment .........................................................4

3.1 System requirements ...........................................................4

3.2 Development toolchains .........................................................4

3.3 Demonstration software .........................................................4

4 Conventions.......................................................................5

5 Quick start ........................................................................6

5.1 Getting started .................................................................6

6 Hardware layout and configuration.................................................7

6.1 PCB layout ....................................................................7

6.2 Mechanical drawing ............................................................9

6.3 Embedded STLINK-V3E .......................................................11

6.3.1 Drivers ............................................................... 11

6.3.2 STLINK-V3E firmware upgrade.............................................11

6.4 Power supply .................................................................12

6.4.1 Debugging while using VIN or EXT as an external power supply ...................14

6.5 Clock sources ................................................................14

6.6 Board functions ...............................................................15

6.6.1 LEDs.................................................................15

6.6.2 Push button............................................................16

6.6.3 Current consumption measurement (IDD).....................................16

6.6.4 Virtual COM port (VCP): USART............................................16

6.7 Solder bridges ................................................................16

7 Board connectors ................................................................19

7.1 STLINK-V3E USB Micro-B connector CN1 ........................................19

UM2397 - Rev 1

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UM2397

Contents

7.2 Arduino Nano V3 connectors....................................................19

8 STM32G4 Nucleo-32 I/O assignment ..............................................23

9 Federal Communications Commission (FCC) and Industry Canada (IC) Compliance

Statements .......................................................................24

9.1 FCC Compliance Statement ....................................................24

9.2 IC Compliance Statement ......................................................24

Revision history .......................................................................25

Contents ..............................................................................26

List of tables ..........................................................................28

List of figures..........................................................................29

UM2397 - Rev 1

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UM2397

List of tables

List of tables

Table 1. List of available products...............................................................3

Table 2. Codification explanation ...............................................................3

Table 3. ON/OFF convention ..................................................................5

Table 4. Jumper configuration .................................................................6

Table 5. External power sources: VIN (7 V - 12 V) .................................................. 13

Table 6. External power sources: 3V3 ........................................................... 13

Table 7. External power sources: 5V............................................................ 14

Table 8. USART2 connection................................................................. 16

Table 9. Solder bridge configuration ............................................................ 16

Table 10. USB Micro-B connector CN1 pinout ...................................................... 19

Table 11. Arduino connector pinout ............................................................. 22

Table 12. Nucleo-32 I/O assignment.............................................................23

Table 13. Document revision history ............................................................. 25

UM2397 - Rev 1

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UM2397

List of figures

List of figures

Figure 1. NUCLEO-G431KB top view ...........................................................1

Figure 2. NUCLEO-G431KB bottom view ........................................................1

Figure 3. Hardware block diagram .............................................................7

Figure 4. Top layout .......................................................................8

Figure 5. Bottom layout .....................................................................9

Figure 6. STM32G4 Nucleo 32 board mechanical drawing (in millimeter) .................................. 10

Figure 7. USB composite device.............................................................. 11

Figure 8. STM32G4 Nucleo-32 board power tree .................................................. 12

Figure 9. STM32G431KB Nucleo-32 board clock configuration ......................................... 15

Figure 10. USB Micro-B connector CN1 (front view) ................................................. 19

Figure 11. Arduino connectors ................................................................ 20

Figure 12. Arduino connector pinout ............................................................ 21

UM2397 - Rev 1

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UM2397

IMPORTANT NOTICE – PLEASE READ CAREFULLY

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Information in this document supersedes and replaces information previously supplied in any prior versions of this document.

© 2019 STMicroelectronics – All rights reserved

UM2397 - Rev 1

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