STMicroelectronics STM32L476 User Manual

UM1879

User manual

Discovery kit with STM32L476VG MCU

Introduction

The STM32L476 Discovery kit (32L476GDISCOVERY) helps the user to discover the
STM32L4 ultra-low-power features and to develop and share applications.

It is based on the STM32L476VGT6 microcontroller with three I2Cs, three SPIs, six
USARTs, CAN, SWPMI, two SAIs, 12-bit ADCs, 12-bit DAC, LCD driver, internal 128
of SRAM and 1
controller, FMC, JTAG debugging support.

The 32L476GDISCOVERY includes an ST-LINK/V2-1 embedded debugging tool interface,
LCD (24 segments, 4 commons), LEDs, push-button, joystick, USB OTG FS, audio DAC,
MEMS (microphone, 3-axis gyroscope, 6-axis compass), Quad-SPI Flash memory,
embedded ammeter measuring STM32 consumption in low-power mode.

External boards can be connected through the extension and probing connectors.

Mbyte of Flash memory, Quad-SPI, touch sensing, USB OTG FS, LCD

Kbytes

Figure 1. STM32L476 Discovery board

Picture is not contractual.

June 2018 UM1879 Rev 4 1/41

www.st.com

1

Contents UM1879

Contents

1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

2 Product marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3 System requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4 Development toolchains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5 Demonstration software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

6 Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

7 Delivery recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

8 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

9 Bootloader limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

10 Hardware layout and configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

10.1 Embedded ST-LINK/V2-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

10.1.1 Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

10.1.2 ST-LINK/V2-1 firmware upgrade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

10.1.3 Using ST-LINK/V2-1 to program/debug the STM32L476VGT6

on board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

10.1.4 Using ST-LINK/V2-1 to program/debug an external STM32 application

board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

10.2 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

10.3 Clock source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

10.4 Reset source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

10.5 User interface: LCD, joystick, LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

10.6 Boot0 configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

10.7 Quad-SPI NOR Flash memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

10.8 USB OTG FS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

10.9 USART configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

10.10 Audio DAC and MEMS microphone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2/41 UM1879 Rev 4

UM1879 Contents

10.11 9-axis motion sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

10.12 I

2

C extension connector CN2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

10.13 MCU current ammeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

10.14 Extension connector P1 and P2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

10.15 Solder bridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

11 Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Appendix A Power consumption measurements . . . . . . . . . . . . . . . . . . . . . . . . 35

Appendix B Mechanical drawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Appendix C Compliance statements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

C.1 FCC Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

C.1.1 Part 15.19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

C.1.2 Part 15.105 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

C.1.3 Part 15.21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

C.2 IC Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

C.2.1 Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

C.2.2 Déclaration de conformité . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

UM1879 Rev 4 3/41

3

List of tables UM1879

List of tables

Table 1. Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 2. ON/OFF conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 3. Jumper states . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Table 4. Debug connector CN4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Table 5. Reset related jumper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Table 6. Connector CN2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Table 7. Extension connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Table 8. Solder bridges. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Table 9. Typical power consumption of the STM32L476 Discovery board. . . . . . . . . . . . . . . . . . . . 36

Table 10. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

4/41 UM1879 Rev 4

UM1879 List of figures

List of figures

Figure 1. STM32L476 Discovery board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Figure 2. Hardware block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 3. STM32L476 Discovery board top layout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 4. STM32L476 Discovery board bottom layout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 5. Updating the list of drivers in device manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 6. CN1, CN3 (ON), CN4 connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 7. CN1, CN3 (OFF), CN4 connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 8. Board jumper location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 9. Connector CN2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 10. STM32L476 Discovery board design top sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 11. ST-LINK/V2-1 with support of SWD only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 12. STM32L476VGT6 MCU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 13. IDD measurement / MFX (Multi Function eXpander) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Figure 14. Joystick ACP, LEDs and push-button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 15. LCD display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 16. OTG USB FS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 17. Audio DAC and microphone MEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Figure 18. Quad-SPI Flash memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Figure 19. Gyroscope, accelerometer, magnetometer MEMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Figure 20. Power consumption tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Figure 21. STM32L476 Discovery board mechanical drawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

UM1879 Rev 4 5/41

5

Features UM1879

1 Features

• STM32L476VGT6 microcontroller featuring 1 Mbyte of Flash memory and 128 Kbytes
of RAM in LQFP100 package

• On-board ST-LINK/V2-1 supporting USB reenumeration capability

• Three different interfaces supported on USB:

– Virtual Com Port

– Mass storage

– Debug port

• Arm

®

Mbed enabled

• LCD 24 segments, 4 commons in DIP 28 package

• Seven LEDs:

– LD1 (red/green) for ST-LINK/V2-1 USB communication

– LD2 (red) for 3.3 V power on

– LD3 overcurrent (red)

– LD4 (red), LD5 (green) two user LEDs

– LD6 (green), LD7 (red) USB OTG FS LEDs

• Push-button (reset)

• Four-direction joystick with selection

• USB OTG FS with Micro-AB connector

• SAI Audio DAC, stereo with output jack

• Digital microphone MEMS

• Accelerometer and magnetometer MEMS

• Gyroscope MEMS

• 128-Mbit Quad-SPI Flash memory

• STM32 current ammeter with 4 ranges and auto calibration

2

• I

C extension connector for external board

• Four power supply options:

–ST-LINK/V2-1

– USB FS connector

– External 5V

– CR2032 battery (not provided)

• Extension connectors

• Comprehensive free software including a variety of examples, part of STM32Cube™

package

™(a)

(see http: //mbed.org)

a. Arm and Mbed are registered trademarks or trademarks of Arm Limited (or its subsidiaries) in the US and/or

elsewhere.

6/41 UM1879 Rev 4

UM1879 Product marking

2 Product marking

Evaluation tools marked as “ES” or “E” are not yet qualified and are therefore not ready to
be used as reference design or in production. Any consequences arising from such usage
will not be at STMicroelectronics’ charge. In no event will STMicroelectronics be liable for
any customer usage of these engineering sample tools as reference designs 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 section Package information in the STM32 datasheet at www.st.com).

• next to the evaluation tool ordering part number, that is stuck or silkscreen 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.

3 System requirements

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

• USB Type-A to Micro-B cable

4 Development toolchains

• Keil® MDK-ARM

• IAR™ EWARM

• GCC-based IDEs including free SW4STM32 from AC6

• Arm

®

Mbed™ online (see http://mbed.org)

(b)

(b)

®(a)

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

b. On Windows only

UM1879 Rev 4 7/41

40

Demonstration software UM1879

5 Demonstration software

The demonstration software, included in the STM32Cube MCU Package corresponding to
the on-board MCU, 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 the
discovery web page.

www.st.com/stm32l4-

6 Ordering information

To order the 32L476GDISCOVERY Discovery kit, refer to Tab le 1.

Order code Target STM32

32L476GDISCOVERY STM32L476VGT6

Table 1. Ordering information

7 Delivery recommendations

Some verifications are needed before using the board for the first time to make sure that
nothing has been damaged during the shipment and that no components are unplugged or
lost. When the board is extracted from its plastic bag, check that no component remains in
the bag. In particularly, make sure that the following jumpers on top side of the board are
plugged: CN3, JP3, JP5, and JP6.

The battery CR2032 is not provided.

8 Conventions

Table 2 provides conventions used in the present document.

Convention Definition

Jumper JPx ON Jumper fitted

Jumper JPx OFF Jumper not fitted

Solder bridge SBx ON SBx connections closed by solder

Table 2. ON/OFF conventions

Solder bridge SBx OFF SBx connections left opened

8/41 UM1879 Rev 4

UM1879 Bootloader limitations

9 Bootloader limitations

Boot from system Flash memory results in executing bootloader code stored in the system
Flash memory protected against writing and erasing. This allows in-system programming
(ISP), that is, flashing the STM32 user Flash memory. It also allows writing data into RAM.
The data come in via one of communication interfaces such as USART, SPI, I
or CAN.

Bootloader version can be identified by reading the Bootloader ID at the address
0x1FFF6FFE.

The STM32L476VGT6 part soldered on the 32L476GDISCOVERY main board is marked
with a date code corresponding to its date of manufacturing. STM32L476VGT6 parts with
the date code prior or equal to week 22 of 2015 are fitted with bootloader V
the limitations to be worked around, as described hereunder. Parts with the date code
starting from week 23 of 2015 contain bootloader V
exist.

To locate the visual date code information on the STM32L476VGT6 package, refer to its
datasheet (DS10198) available at www.st.com, section Package Information. Date code
related portion of the package marking takes Y
year and WW is the week. For example, a part manufactured in week 23 of 2015 bares the
date code 5

23.

9.2 in which the limitations no longer

WW format, where Y is the last digit of the

2

C bus, USB

9.0 affected by

Bootloader ID of the bootloader V 9.0 is 0x90.

The following limitations exist in the bootloader V 9.0:

1. RAM data get corrupted when written via USART/SPI/I2C/USB interface

Description:

Data write operation into RAM space via USART, SPI, I2C bus or USB results in wrong
or no data written.

Workaround:

To correct the issue of wrong write into RAM, download the STSW-STM32158
bootloader V
V9.0 SRAM patch" to the MCU, following the information in readme.txt file available in
the package.

2. User Flash memory data get corrupted when written via CAN interface

Description:

Data write operation into user Flash memory space via CAN interface results in wrong
or no data written.

Workaround:

To correct the issue of wrong write into Flash memory, download the STSW-STM32158
bootloader V
CAN patch" to the MCU, following the information in readme.txt file available in the package.

9.0 patch package from the www.st.com website and load "Bootloader

0.9 patch package from the www.st.com website and load "Bootloader V9.0

UM1879 Rev 4 9/41

40

Hardware layout and configuration UM1879

A to Mini-B

USB

Embedded

ST_LINK/V2-1

(3V CR2032 Battery)

CR1

SWDHeader P1

Header P2

STM32L476VGT6

power

JP6

IO

IO

reset

9-axis motion

sensors

digital

microphone

MEMS

SAI Audio DAC

stereo

LCD segment
(4x24)

128Mb
QuadSPI flash

USB OTG FS with
Micro-A-B
connector

IDD current
measurement

Reset
pushbutton

Joystick with
4-direction
control and
selector

User LEDs

LD5 (green)

LD4 (red)

IO

10 Hardware layout and configuration

The STM32L476 Discovery board is designed around the STM32L476VGT6 (100-pin LQFP
package). The hardware block diagram (see
the STM32L476VGT6 and the peripherals (9-axis motion sensors, digital microphone
MEMS, LCD segment, 128

Mbytes of Quad-SPI Flash memory, SAI Audio DAC stereo with

3.5mm output jack, USB OTG FS, IDD current measurement, LEDs, push-button, joystick)

and the

Figure 3 will help to locate these features on the STM32L476 Discovery board.

Figure 2. Hardware block diagram

Figure 2) illustrates the connection between

10/41 UM1879 Rev 4

UM1879 Hardware layout and configuration

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Figure 3. STM32L476 Discovery board top layout

UM1879 Rev 4 11/41

40

Hardware layout and configuration UM1879

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Figure 4. STM32L476 Discovery board bottom layout

12/41 UM1879 Rev 4

UM1879 Hardware layout and configuration

10.1 Embedded ST-LINK/V2-1

The ST-LINK/V2-1 programming and debugging tool is integrated on the STM32L476
Discovery board. Compared to ST-LINK/V2 the changes are listed below.
The new features supported on ST-LINK/V2-1 are:

• USB software re-enumeration

• Virtual Com Port interface on USB

• Mass storage interface on USB

• USB power management request for more than 100mA power on USB

These features are no more supported on ST-LINK/V2-1:

• SWIM interface

• Application voltage lower than 3 V

For all general information concerning debugging and programming features common
between V2 and V2-1 refer to ST-LINK/V2 in-circuit debugger/programmer for STM8 and
STM32 User manual (UM1075).
There are two different ways to use the embedded ST-LINK/V2-1 depending on the jumper
states:

• Program/debug the STM32L476VGT6 on board (Section 10.1.3)

• Program/debug an STM32 in an external application board using a cable connected to

SWD connector CN4 (Section 10.1.4)

.

Table 3. Jumper states

Jumper state Description

Both CN3 jumpers ON ST-LINK/V2-1 functions enabled for on-board programming (default)

Both CN3 jumpers OFF

10.1.1 Drivers

The ST-LINK/V2-1 requires a dedicated USB driver, which can be found on the www.st.com
website.

In case the STM32L476 Discovery board is connected to the PC before the driver is
installed, some interfaces may be declared as “Unknown” in the PC device manager. In this
case the user must install the driver files, and update the driver of the connected device
from the device manager.

ST-LINK/V2-1 functions enabled for external board through external
CN4 connector (SWD supported)

UM1879 Rev 4 13/41

40

Hardware layout and configuration UM1879

Figure 5. Updating the list of drivers in device manager

1. Prefer using the “USB Composite Device” handle for a full recovery.

10.1.2 ST-LINK/V2-1 firmware upgrade

The ST-LINK/V2-1 embeds a firmware upgrade mechanism for in-situ upgrade through the
USB port. As the firmware may evolve during the life time of the ST-LINK/V2-1 product (for
example a new functionality, bug fixes, support for new microcontroller families), it is
recommended to visit the www.st.com website before starting to use the STM32L476
Discovery board and periodically, in order to stay up-to-date with the latest firmware version.

10.1.3 Using ST-LINK/V2-1 to program/debug the STM32L476VGT6 on board

To program the STM32L476VGT6 on board, simply plug in the two jumpers on CN3, as
shown in
the Mini-B USB ST-LINK/V2-1 CN1 connector.
Make sure the jumpers JP3, JP6.3V3, and JP5.ON are set.

Do not use the CN4 connector.

Figure 6 in red, and connect the STM32L476 Discovery board to the PC through

Figure 6. CN1, CN3 (ON), CN4 connections

14/41 UM1879 Rev 4

UM1879 Hardware layout and configuration

10.1.4 Using ST-LINK/V2-1 to program/debug an external STM32 application board

To use the ST-LINK/V2-1 to program the STM32 on an external application board (out of the
STM32L476VGT6 on board), remove the two jumpers from CN3 as shown in
red, and connect the board to the CN4 software debug connector according to Table 4.

Make sure the jumpers JP6.3V3, and JP5.OFF are set.

JP3, must be ON if CN4 pin 5 (NRST) is used in the external application board.

Pin CN4 Designation

1 Vapp VDD from application

2 SWLCK SWD clock

3 GND Ground

4 SWDIO SWD data input/output

5 NRST RESET of target MCU

6SWO Reserved

Table 4. Debug connector CN4

Figure 7 in

Figure 7. CN1, CN3 (OFF), CN4 connections

UM1879 Rev 4 15/41

40

Hardware layout and configuration UM1879

10.2 Power supply

The power supply is provided with four options:

– ST-LINK/V2-1: CN1

– CR2032 battery (not provided): CR1

– External 5V: 5V_I

– USB FS connector: USB USER CN7

• ST-LINK/V2-1:

JP6 needs to be placed in position 3V3. JP3 is closed. JP5 is in position ON. CN3
jumpers are ON.

The STM32L476G Discovery board can be powered from the ST-LINK USB connector
CN1 (5V_USB_ST_LINK). Only the ST-LINK circuit has the power before the USB
enumeration, as the host PC only provides 100mA to the board at that time.

During the USB enumeration, the STM32L476 Discovery board requires 300 mA of
current to the host PC. If the host is able to provide the required power, the
STM32L476 is powered and the red LED LD2 is turned ON, thus the STM32L476
Discovery board and its extension board can consume no more than 300 mA current. If
the host is not able to provide the required current, the STM32L476 and the extension
board are not power supplied. As a consequence the red LED LD2 remains turned
OFF. In such case it is mandatory to use an external power supply, as explained in the
next section.

Warning: If the maximum current consumption of the STM32L476

Discovery board and its extension board exceeds 300 mA, it
is mandatory to power the STM32L476 Discovery board using
an external power supply connected to 5V_I.

Note: In case this board is powered by a USB charger or a USB battery connected on CN1, there

is no USB enumeration, the led LD2 remains OFF and the STM32L476 is not powered. In
this specific case only, fit the jumper JP2 to allow the STM32L476 to be powered anyway.
Remove this jumper JP2 if then a host PC is connected to the ST-LINK/V2-1 CN1 connector
to supply the board.

• CR2032 battery inserted in CR1 (bottom side):

– The CR2032 battery is not provided

– JP6 needs to be placed in position BATT. JP3 is opened. JP5 is in position ON

– The battery supplies the 3V3 and 3V power domains on board. All the peripherals

are powered, except the ST-LINK, which can only be supplied through the USB
connector CN1

• External 5V_I or USB USER CN7 (USB FS connector):

– External 5V_I: The pin 3 5V_I of P2 header can be used as input for an external

power supply. In this case, the STM32L476 Discovery board must be powered by
a power supply unit or by an auxiliary equipment complying with the standard EN­60950-1: 2006+A11/2009, and must be Safety Extra Low Voltage (SELV) with a
limited power capability.

– To use the USB USER CN7 to power supply the board, a jumper needs to be

placed between VUSB pin 4 and the pin 3 5V_I of P2 header (see Figure 8).

16/41 UM1879 Rev 4

UM1879 Hardware layout and configuration

Figure 8. Board jumper location

In this condition it is still possible to use the USB ST-LINK for communication, for
programming or debugging, but it is mandatory to power supply the board first using
5V_I or USB USER CN7 then connect the USB ST-LINK cable to the PC. Proceeding
this way ensures that the enumeration occurs thanks to the external power source.

The following power sequence procedure must be respected:

1. Connect the external power source to 5V_I or USB USER CN7.

2. Power on the external power supply 5V_I or USB USER CN7.

3. Check that LD2 is turned ON.

4. Connect the PC to USB ST-LINK connector CN1.

If this order is not respected, the board may be supplied by 5V_USB_ST_LINK first
then by 5V_I or USB USER CN7 and the following risks may be encountered:

1. If more than 300 mA current is needed by the board, the PC may be damaged or the

current supply can be limited by the PC. As a consequence the board is not powered
correctly.

2. 300 mA is requested at enumeration (since JP2 must be OFF) 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 LD2 remains OFF).

Note: The headers pins 5V (except in battery mode), 3V3, 2V5, 3V can be used as output power

supply when an extension board is connected to the P1 and P2 headers. The power
consumption of the extension board must be lower than 100 mA.

UM1879 Rev 4 17/41

40

Hardware layout and configuration UM1879

10.3 Clock source

The STM32L476VGT6 MCU uses:

• A 32.768 KHz low-speed source:

– By default, the X3 crystal on board

– From an external oscillator through P2 header (pin 7 labeled ‘PC14’). The

configuration needed is:

SB19 opened, SB20 closed, R26 removed

• A system clock source:

– By default, generated by an internal STM32L476VGT6 oscillator. The

configuration needed is:

SB18 opened, SB21 and SB22 closed

– Or driven by an X2 Crystal on board (not fitted). The configuration needed is:

SB18, SB21 and SB22 opened

X2, R88, R89, C77, C78 fitted

– Or driven by a MCO signal (8MHz) from the ST-LINK MCU STM32F103CBT6

(U3).The configuration needed is:

SB18 closed, SB22 opened

R89 not fitted

– Or driven externally from PH0 through the P2 header, pin 9 labeled ‘PH0’.The

configuration needed is:

SB22 closed, SB18 opened

R89 not fitted

Note: Refer to Oscillator design guide for STM8S, STM8A and STM32 microcontrollers

Application note (AN2867).

10.4 Reset source

The reset signal NRST of the STM32L476 Discovery board is low active and the reset
sources include:

• The reset button B1, connected by default to NRST (SB23 closed)

• The embedded ST-LINK/V2-1

• The external reset pin 11 of P2 header connector, labeled ‘NRST’

• The external reset from SWD connector CN4, pin 5

Jumper Description

JP3

Table 5. Reset related jumper

When JP3 is closed, the SWD connector CN4 pin 5 and the embedded
ST-LINK/V2-1 are connected to NRST.

Default Setting: closed

JP3 is opened, no connection between CN4 and ST-LINK/V2-1 to
NRST. This must be used when the ST-LINK/V2-1 is not powered (i.e
STM32L476 Discovery board) is powered by the CR2032 battery

18/41 UM1879 Rev 4

UM1879 Hardware layout and configuration

10.5 User interface: LCD, joystick, LEDs

The STM32L476 Discovery board features sept LEDs with the following functionalities:

• LD1 COM: LD1 default status is red. LD1 turns to green to indicate that

communications are in progress between the PC and the ST-LINK/V2-1

• LD2 PWR: the red LED indicates that the board is powered

• LD3 OC: the red LED indicates a fault when the board is in current limit (510 mA)

• LD4 user: the red LED is a user LED connected to the I/O PB2 of the

STM32L476VGT6

• LD5 user: the green LED is a user LED connected to the I/O PE8 of the

STM32L476VGT6

• LD6, LD7: USB OTG FS LEDs, see Section 10.8

Four-direction joystick (B2) with selection and a reset push-button (B1) are available as
input devices.

An LCD 4x24 segments, 4 commons, multiplexed 1/4 duty, 1/3 bias is mounted on the
DIP28 connector U5.

10.6 Boot0 configuration

Boot0 is by default grounded through a pull-down R91.

It is possible to set Boot0 high, removing R91 and putting a jumper between P1 header
pin 6 BOOT0 and pin 5 3V.

10.7 Quad-SPI NOR Flash memory

128-Mbit Quad-SPI NOR Flash memory is connected to Quad-SPI interface of
STM32L476VGT6.

10.8 USB OTG FS

The STM32L476 Discovery board supports USB OTG Full Speed communication via a USB
Micro-AB connector (CN7) and a USB power switch (U14) connected to VBUS. The board
can be powered by this USB connection as described in

A green LED LD6 will be lit in one of these cases:

• The power switch (U14) is ON and STM32L476 Discovery board works as a USB host

• VBUS is powered by another USB host when STM32L476 Discovery board works as a

USB device

Red LED LD7 will be lit when an overcurrent occurs.

In order to connect the OTG_FS_VBUS and OTG_FS_ID signals from the connector CN7 to
the OTG FS hardware IP of STM32L476VGT6, remove the LCD from its socket U5, and
close SB24 and SB25.

Section 10.2.

The default configuration is: the LCD is connected to U5, and SB24 and SB25 are opened.
In this case the OTG_FS_VBUS and OTG_FS_ID signals from CN7 are connected to the
OTG FS peripheral of the STM32L476VGT6 available on PC11 and PC12.

UM1879 Rev 4 19/41

40

Hardware layout and configuration UM1879

069

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

10.9 USART configuration

The USART interface available on PD5 and PD6 of the STM32L476VGT6 can be
connected to the ST-LINK MCU to use the Virtual Com Port function.

To use the Virtual Com Port function with:

• The on-board STM32L476VGT6: set SB13 and SB16 ON (SB15, SB17 must be OFF).

• An external MCU: remove solder from SB13 and SB16, solder a two pins header on

JP4, then RX and TX of the external MCU can be connected directly to RX and TX of
JP4.

(For more details see Section 11 : S c h e m a ti c s )

10.10 Audio DAC and MEMS microphone

An audio stereo DAC CS43L22 (U13) is connected to SAI interface of STM32L476VGT6.

The STM32L476VGT6 controls the audio DAC via the I2C1 bus which is shared with the I2C
extension connector CN2.

I2C1 is also available on the connector P1, pins labeled ‘PB6’ (I2C1_SCL) and ‘PB7’
(I2C1_SDA).

The stereo output jack connector is CN6.

Note: I2C address of CS43L22 is 0x94.

A MEMS audio sensor omnidirectional digital microphone provides a digital signal in PDM
format to the STM32L476VGT6.

10.11 9-axis motion sensors

STM32L476 Discovery board supports some 9-axis motion sensors, composed of:

• L3GD20 (U7): a three-axis digital output gyroscope

• LSM303C (U6): a 3D accelerometer and 3D magnetometer module

which are connected to STM32L476VGT6 through SPI.

10.12 I2C extension connector CN2

Figure 9. Connector CN2

20/41 UM1879 Rev 4

UM1879 Hardware layout and configuration

Pin number Description Pin number Description

1 I2C1_SDA (PB7) 5 +3V3

2NC6NC

3 I2C1_SCL (PB6) 7 GND

4 EXT_RST(PD0) 8 NC

10.13 MCU current ammeter

The jumper JP5, labeled Idd, allows the consumption of STM32L476VGT6 to be measured
directly by a built-in current ammeter circuit able to measure from 60nA to 50mA or by
removing the jumper and connecting an ammeter:

• Jumper on position OFF: STM32L476VGT6 is powered (default).

Table 6. Connector CN2

• Jumper on position ON: an on-board module is designed to measure from 60nA to

50mA by using several MOSFETs and switching automatically depending on the read
value.

• No jumper on JP5: an ammeter must be connected to measure the STM32L476VGT6

current through pin 1 and 2 (if there is no ammeter, the STM32L476VGT6 is not
powered).

UM1879 Rev 4 21/41

40

Hardware layout and configuration UM1879

10.14 Extension connector P1 and P2

The P1 and P2 headers can connect the STM32L476 Discovery board to a standard
prototyping/wrapping board. STM32L476VGT6 GPIOs are available on these connectors.

P1 and P2 can also be probed by an oscilloscope, logical analyzer or voltmeter.

P1 P2

Pin number function Pin number function

Table 7. Extension connector

13V3 1

2 GND 2 GND

32V5 3

4GND 4

53V 5 5V

6BOOT0 6 GND

7 PB3 7 PC14

8 PB2 8 PC15

9 PE8 9 PH0

10 PA0 10 PH1

11 PA5 11 NRST

12 PA1 12 GND

13 PA2 13 PE11

14 PA3 14 PE10

15 PB6 15 PE12

16 PB7 16 PE13

(USB OTG FS VBUS)

5V_U

(5V_USB_ST_LINK)

5V_I

(5V INPUT)

VUSB

17 PD0 17 PE14

18 NC 18 PE15

19 GND 19 GND

20 GND 20 GND

22/41 UM1879 Rev 4

UM1879 Hardware layout and configuration

10.15 Solder bridges

Table 8 describes each solder bridge. The default state is indicated in bold.

Bridge State Description

Table 8. Solder bridges

SB1 (ST-LINK PWR)

SB2 (EXT/RF E2P)

SB3, SB4, SB7, SB8
(RESERVED)

SB5, SB6, SB9, SB10 (DEFAULT) ON Reserved, do not modify

SB11 (STM_RST)

SB12 OFF Reserved

SB16, SB13 (USART RX, TX)

SB17, SB15 (MFX USART RX,TX)

SB14 (T_SWO)

SB18 (MCO)

ON ST-LINK module is powered

OFF ST-LINK module is not powered

ON 5V connected to CN2.8

OFF 5V is not connected to CN2.8

OFF Reserved, do not modify

ON No incidence on NRST signal of STM32F103CBT6

OFF

OFF

OFF

OFF

OFF MCO is not connected to PH0

NRST signal of STM32F103CBT6 is connected to
GND

PA2, PA3 of STM32F103CBT6 are connected to PD6,

ON

PD5 of STM32L476VGT6

PA2, PA3 of STM32F103CBT6 are not connected to
PD6, PD5 of

PA2, PA3 of STM32L476VGT6 are connected to MFX

ON

USART RX,TX

PA2, PA3 of STM32L476VGT6 are not connected to
MFX USART RX,TX

PA10 of STM32F103CBT6 is connected to PB3 of

ON

STM32L476VGT6

PA10 of STM32F103CBT6 is not connected to PB3 of
STM32L476VGT6

ON If SB22 is also ON, MCO is connected to PH0

STM32L476VGT6

SB19, SB20 (32.768kHz CLK)

SB21, SB22 (8MHz CLK)

SB23 (B1-RESET)

ON PC14, PC15 are connected to X3 crystal

OFF PC14, PC15 are not connected to X3 crystal

ON PH0, PH1 are connected to X2 crystal (X2 is not fitted)

OFF PH0, PH1 are not connected to X2 crystal

B1 push-button is connected to NRST of STM32L476

ON

Discovery board

OFF

UM1879 Rev 4 23/41

B1 push-button is not connected to NRST of
STM32L476 Discovery board

40

Hardware layout and configuration UM1879

Table 8. Solder bridges (continued)

Bridge State Description

OTG_FS_VBUS signal is connected to PA9

ON

SB24, SB25 (OTG FS)

OFF

SB26 ON Reserved, do not modify

SB27 OFF Reserved, do not modify

SB28 (2.5V REG inhibit)

OFF U12 input is not inhibited

OTG_FS_ID signal is connected to PA10

OTG_FS_VBUS signal is not connected to PA9
OTG_FS_ID signal is not connected to PA10

ON U12 (2.5V regulator) input is inhibited

SB29 (2.5V REG input)

ON 5V is connected to U12 input

OFF 5V is not connected to U12 input

24/41 UM1879 Rev 4

110

STM32L476 Discovery

MB1184 C-01

6/15/2015

Title:

Size: Referenc e:

Date: Sheet: of

A4

Revision:

STM32L476G-DISCOProject:

SWDIO

SWCLK

MCO

NRST

NRST

MCO

LD_R

SWCLK
SWDIO

USART_TX

USART_RX

LD_G

MFX_IRQ_OUT

MFX_WAKEUP

QSPI_D0

QSPI_D3

QSPI_D2

QSPI_D1

QSPI_CLK

QSPI_CS

SAI1_FS

SAI1_SD

SAI1_SCK

I2C1_SCL

I2C1_SDA

AUDIO_RST

SAI1_MCK

AUDIO_DIN
AUDIO_CLK

OTG_FS_PowerSwitchOn

OTG_FS_DM

OTG_FS_DP

OTG_FS_ID

OTG_FS_VBUS

OTG_FS_OverCu rrent

SEG[0..23]

COM[0..3]

EXT_RST

PH[0..1]

JOY_CENTER

JOY_DOWN

JOY_LEFT

JOY_RIGHT

JOY_UP

MEMS_SCK

MEMS_MISO

MEMS_MOSI

GYRO_CS

GYRO_INT1

GYRO_INT2

XL_CS

XL_INT

MAG_CS

MAG_DRDY

MAG_INT

MFX_USART3_RX
MFX_USART3_TX

MFX_I2C_SDA
MFX_I2C_SCL

BOOT0

SWO

3V3_REG-ON

PC14
PC15

U_STM32Lx
STM32Lx.SchDoc

Rev A-01 --> PCB label MB1184 A-0 1
Rev B-01 --> PCB label MB1184 B-01, Remove R91, Replace COM4..7 by COM0..3,
Add SB for USB_OTG, add VBUS on P2 for USB USE R power supply
Rev C-01 --> PCB label MB1184 C-01, Remove

SWCLK and SWO shorted,

Replaced on P1, PB8..9 by PB6..7.

--> MP45DT02 replaced by MP34DT01

--> Xta l 32.768kHz replaced by NX3215SA

--> Change values of C27, C25 : C27=C25=4.7pF

USART_TX

USART_RX

3V

GND

GND

NRST

PC14
PC15

PH1

PH0

BOOT0

5V_IN

5V

SWDIO

SWCLK

MCO

NRST

USART_RX
USART_TX

MFX_USART3_RX
MFX_USART3_TX

SWO

3V3_REG-ON

U_ST_LINK_V2-1
ST_LINK_V2-1.SCHDOC

MFX_WAKEUP
MFX_IRQ_OUT
MFX_I2C_SDA
MFX_I2C_SCL
MFX_USART3_RX
MFX_USART3_TX
NRST

U_IDD_measurement
IDD_measurement.SchDoc

MFX_I2C_SCL

MFX_I2C_SDA

MFX_IRQ_OUT

MFX_WAKEUP

MFX_USART3_RX
MFX_USART3_TX

MFX_USART3_RX
MFX_USART3_TX

3V3

AUDIO_CLK

AUDIO_DIN

AUDIO_RST

SAI1_FS

SAI1_SD

SAI1_SCK

I2C1_SCL

I2C1_SDA

SAI1_MCK

U_AUDIO
AUDIO.SchDoc

OTG_FS_PowerSwitchOn
OTG_FS_OverCu rrent
OTG_FS_DM
OTG_FS_DP
OTG_FS_ID
OTG_FS_VBUS

U_USB_OTG_FS
USB_OTG_FS.SchDoc

NRST
LD_R
LD_G

EXT_RST

JOY_CENTER
JOY_DOWN
JOY_LEFT
JOY_RIGHT
JOY_UP

I2C1_SCL
I2C1_SDA

U_Peripherals
Peripherals.SchDoc

SEG[0..23]
COM[0..3]

U_LCD_GH08172
LCD_GH08172.SchDoc

I2C1_SCL

I2C1_SDA

SAI1_MCK
SAI1_SCK
SAI1_SD
SAI1_FS

AUDIO_RST
AUDIO_DIN
AUDIO_CLK

SEG[0..23]
COM[0..3]

OTG_FS_PowerSwitchOn
OTG_FS_OverCu rrent
OTG_FS_DM
OTG_FS_DP
OTG_FS_ID
OTG_FS_VBUS

NRST
LD_R
LD_G

EXT_RST

JOY_CENTER
JOY_DOWN
JOY_LEFT
JOY_RIGHT
JOY_UP

I2C1_SCL
I2C1_SDA

PH[0..1]

QSPI_D0

QSPI_D3

QSPI_D2

QSPI_D1

QSPI_CLK

QSPI_CS

U_QSPI
QSPI.SchDoc

QSPI_D0
QSPI_D1
QSPI_D2
QSPI_D3

QSPI_CS
QSPI_CLK

GYRO_CS

MAG_CS

MAG_INT

XL_INT

MAG_DRDY

MEMS_SCK

MEMS_MISO

MEMS_MOSI

GYRO_INT1

GYRO_INT2

XL_CS

U_MEMS
MEMS.SchDoc

GYRO_INT1

GYRO_INT2

MEMS_SCK

GYRO_CS

MEMS_MISO

MEMS_MOSI

MAG_CS

XL_CS

MAG_DRDY

XL_INT

MAG_INT

NRST

SEG[0..23]

COM[0..3]

LD_R
LD_GEXT_RST

JOY_CENTER
JOY_DOWN
JOY_LEFT
JOY_RIGHT
JOY_UP

I2C1_SCL

I2C1_SDA

GYRO_INT1

GYRO_INT2

MEMS_SCK

GYRO_CS

MEMS_MISO

MEMS_MOSI

MAG_CS

XL_CS

MAG_DRDY

XL_INT

MAG_INT

OTG_FS_PowerSwitchOn
OTG_FS_OverCu rrent
OTG_FS_DM
OTG_FS_DP
OTG_FS_ID
OTG_FS_VBUS

SWDIO

SWCLK

MCO

NRST

QSPI_D0
QSPI_D1
QSPI_D2
QSPI_D3

QSPI_CS
QSPI_CLK

SAI1_MCK
SAI1_SCK
SAI1_SD
SAI1_FS

AUDIO_RST
AUDIO_DIN
AUDIO_CLK

USART_TX

USART_RX

BOOT0

MFX_I2C_SCL

MFX_I2C_SDA

MFX_IRQ_OUT

MFX_WAKEUP

MFX_USART3_RX
MFX_USART3_TX

3V3_REG-ON

SWO

SWO

3V3_REG-ON

2V5

GND

GND

Wired on Solder Side

JP8

JP7

5V_USB_ST_LINK

GND

GND

GND

GND

GND

NC

3V3_REG-ON

QSPI_CLK

QSPI_CS

QSPI_D0
QSPI_D1
QSPI_D2
QSPI_D3

JOY_CENTER

JOY_LEFT
JOY_RIGHT
JOY_UP

JOY_DOWN

LD_R
LD_G

EXT_RST

I2C1_SCL
I2C1_SDA

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20

P1

Header 20

1
2
3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20

P2

Header 20

PB2
PE8
PA0
PA5
PA1
PA2
PA3
PB6
PB7
PD0

PE11

PB3

PE10
PE12
PE13
PE14
PE15

OTG_FS_VBUS

PC14
PC15

11 Schematics

UM1879 Rev 4 25/41

Figure 10. STM32L476 Discovery board design top sheet

--> Change values of resistors : R40=R47=6.04k, R49=15k,

UM1879 Schematics

26/41 UM1879 Rev 4

210

ST-LINK/V2-1 with support of SWD only

MB1184 C-01

6/15/2015

Title:

Size: Reference:

Date: Sheet: o f

A4

Revision:

STM32L476G-DISCOProject:

USB_DM

USB_DP

STM_RST

T_JTCK

T_JTCK

T_JTMS

STM_JTMS

STM_JTCK

OSC_IN
OSC_OUT

T_NRST

AIN_1

3V3_ST_LINK

3V3_ST_LINK

SWIM_IN

USB_DM
USB_DP

USB

VCC

1

D-

2

D+

3

ID

4

GND

5

SHELL

6

CN1

USB-MINI-typeB

COM

ST-LINK Power

3V3_ST_LINK

Jumpers ON --> DISCOVERY Selected
Jumpers OFF --> ST-LINK Selected

Board Ident: PC13=0

T_JTCK

T_JTMS

SWD

3V3_ST_LINK

123

4

CN3

SB5 SB3

SB6 SB4

SB9 SB7

SB10 SB8

STM_JTMS

STM_JTCK

SWCLK

SWDIO

SWD

RESERVED

DEFAULT

3V3_ST_LINK

T_SWDIO_IN

T_SWO
LED_STLINK

LED_STLINK

3V3_ST_LINK

Red

_Green

2 1

3 4

LD1

LD_BICOLOR_CMS

SWDIO

SWCLK

TCK/SWCLK

TMS/SWDIO

Not Fitted

MCO

MCO

T_JRST

1
2
3
4
5
6

CN4

5075BMR-05-SM

AIN_1

T_NRST
T_SWO

NRST

T_NRST

SB11

RC Must be very close to STM32F103 pin 29

51

2

GND

3

4

BYPASS

INH

Vin Vout

U1 LD3985M33R

D1

BAT60JFILM

TX
RX

SB16

SB13

USART_RX

USART_TX

Close to JP
Not Fitted

STLINK_TX

STLINK_RX

Not Fitted

LD2
LED, red

C7

100nF

C71

100nFC6100nFC8100nF

C5

1uF

C1

1uF

C2

100nF

C4

100nF

C3

10nF

C10

20pF

C11

20pF

C73
100nF

C72
20pF

1 2

X1

8MHz

3V3_ST_LINK

USB_RENUMn

PWR_EXT

PWR_ENn

3V3_ST_LINK

3

1

2

T1
9013-SOT23

3V3_ST_LINK

USB_RENUMn

PA14
PA13

PWR_ENn

TP2

TP1

EN

1

GND

2

VO

4

NC

5

GND

7

VI

6

PG

3

U4 LD39050PU33R

C14

1uF

C15
100nF

C13

1uF

C12

100nF

3V3_ST_LINK

5 Volts Output

3 Volts Output

5 Volts From External

5V_IN

5V_IN

5 Volts From USB ST-LINK

JP4

3V3_ST_LINK

3V3_ST_LINK

VBAT

1

PA7

17

PC13

2

PA12

33

PC14

3

PB0

18

PC15

4

JTMS/SWDIO

34

OSCIN

5

PB1

19

OSCOUT

6

VSS_2

35

NRST

7

PB2/BOOT1

20

VSSA

8

VDD_2

36

VDDA

9

PB10

21

PA0

10

JTCK/SWCLK

37

PA1

11

PB11

22

PA2

12

PA15/JTDI

38

PA3

13

VSS_1

23

PA4

14

PB3/JTDO

39

PA5

15

VDD_1

24

PA6

16

PB4/JNTRST

40

PB12

25

PB5

41

PB13

26

PB6

42

PB14

27

PB7

43

PB15

28

BOOT0

44

PA8

29

PB8

45

PA9

30

PB9

46

PA10

31

VSS_3

47

PA11

32

VDD_3

48

U3
STM32F103CBT6

5V

D3
STPS1L30A

D2
STPS1L30A

JP1

5V_USB_ST_LINK

5V_USB_ST_LINK

MFX_USART3_RX

MFX_USART3_TX

SB17

SB15

D4

BAT60JFILM

Not Fitted

12

CR1
CR2032 Holder

IN

1

IN

2

ON

3

GND

4

SET

5

OUT

6

OUT

7

FAULT

8

U2

ST890CDR

51

2

GND

3

4

BYPASS

INH

Vin Vout

U12 LD3985M25R

C47

1uF

C48

100nF

C49

10nF

C54

100nF

C55

1uF

2V55V

R11
10K_1%_0402

C9

100nF

123

JP6

D6

STPS1L30A

3V

3V3_REG

R18

4K7_1%_0402

R82

10K_1%_0402

R83

[NA]

R14

100K_1%_0402

R86

100K_1%_0402

R85

4K7_1%_0402

R84

4K7_1%_0402

R1

0_5%_0402

R79

100_1%_0402

R10
10K_1%_0402

R8

0_5%_0402

R9 0_5%_0402

R7

1K5_1%_0402

5V_USB_ST_LINK

R78
36K_1%_0402

R2
1K_1%_0402

R19

2K7_1%_0402

R80
100_1%_0402

R81

100_1%_0402

R17

22_1%_0402

R20

22_1%_0402

R21

22_1%_0402

R22

22_1%_0402

R13

[NA]

R12
10K_1%_0402

JP2

SWO

SB14

T_SWO

PB3

R33

4K7_1%_0402

3V3

3V3

3V3_REG

R4
330_1%_0402

R5
330_1%_0402

3V3_REG-ON

3V3_REG-ON

JP3

R15

[NA]

2.5 Volts Output

SB1

SB29

SB28

T_JTDI

T_JTDO

SWIM

SWIM_RST

SWIM_RST_IN

R6 100K_1%_0402

3V3_REG

SB12

R16

2K7_1%_0402

Ilim = 510mA
Isc= 1.2Ilim to 1.5Ilim = 612mA to 765mA

LD3
LED, red

R3

1K_1%_0402

Figure 11. ST-LINK/V2-1 with support of SWD only

Schematics UM1879

Figure 12. STM32L476VGT6 MCU

310

STM32L476VGT6 MCU

MB1184 C-01

6/15/2015

Title:

Size: Reference:

Date: Sheet: of

A4

Revision:

STM32L476G-DISCOProject:

PA0

Must be close to the MCU

All this block must be very close to the STM32L476

SWCLK
SWDIO

SWDIO

SWCLKPA14

PA13

USART_TX
USART_RX

PD5

USART_TX
USART_RX

PC14-OSC32_IN

PC15-OSC32_OUT

SB19

SB20

Must be close to the Crystal

PE2

1

PE3

2

PE4

3

PE5

4

PE6

5

PC13

7

PC14

8

PC15

9

PH0

12

PH1

13

NRST

14

PC0

15

PC1

16

PC2

17

PC3/VLCD

18

PA0

23

PA1

24

PA2

25

PA3

26

PA4

29

PA5

30

PA6

31

PA7

32

PC4

33

PC5

34

PB0

35

PB1

36

PB2

37

PE7

38

PE8

39

PE9

40

PE10

41

PE11

42

PE12

43

PE13

44

PE14

45

PE15

46

PB10

47

PB11

48

PB12

51

PB13

52

PB14

53

PB15

54

PD8

55

PD9

56

PD10

57

PD11

58

PD12

59

PD13

60

PD14

61

PD15

62

PC6

63

PC7

64

PC8

65

PC9

66

PA8

67

PA9

68

PA10

69

PA11

70

PA12

71

PA13

72

PA14

76

PA15

77

PC10

78

PC11

79

PC12

80

PD0

81

PD1

82

PD2

83

PD3

84

PD4

85

PD5

86

PD6

87

PD7

88

PB3

89

PB4

90

PB5

91

PB6

92

PB7

93

BOOT0

94

PB8

95

PB9

96

PE0

97

PE1

98

U9A

STM32L476VGT6

VBAT

6

VSS4

27

VSS2

74

VREF-

20

VREF+

21

VDDA_ADC

22

VSS5

10

VDDUSB

73

VDD3

100

VSS1

49

VDD2

75

VDD1

50

VDD4

28

VSSA_ADC

19

VDD5

11

VSS3

99

U9B

STM32L476VGT6

PA1
PA2
PA3
PA4
PA5
PA6
PA7
PA8
PA9
PA10
PA11
PA12
PA13
PA14
PA15

PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PB8
PB9
PB10
PB11
PB12
PB13
PB14
PB15

PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
PC8
PC9
PC10
PC11
PC12
PC13

PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
PD8
PD9
PD10
PD11
PD12
PD13
PD14
PD15

PE0
PE1
PE2
PE3
PE4
PE5
PE6
PE7
PE8
PE9
PE10
PE11
PE12
PE13
PE14
PE15

NRST

BOOT0

PC14

PH[0..1]

MCO

PH1-OSC_OUT

SB21

SB22

MCO

1 2

X2
8MHz

SB18

PH0-OSC_INPH0

PH1

QSPI_D0

QSPI_D3

QSPI_D2

QSPI_D1

QSPI_CLK

QSPI_CS

QSPI_D0
QSPI_D1
QSPI_D2
QSPI_D3

QSPI_CS
QSPI_CLK

SAI1_FS

SAI1_SD

SAI1_SCK

I2C1_SCL

I2C1_SDA

AUDIO_RST

SAI1_MCK

AUDIO_DIN
AUDIO_CLK

OTG_FS_PowerSwitchOn

OTG_FS_DM
OTG_FS_DP
OTG_FS_ID

OTG_FS_VBUS

OTG_FS_OverC urrent

SEG[0..23]
COM[0..3]

SEG[0..23]
COM[0..3]

EXT_RST

EXT_RST

LD_R
LD_G

LD_R
LD_G

NRST

NRST

JOY_CENTER
JOY_DOWN
JOY_LEFT
JOY_RIGHT
JOY_UP

JOY_CENTER
JOY_DOWN
JOY_LEFT
JOY_RIGHT
JOY_UP

MFX_USART3_RX

MFX_USART3_TX

MFX_USART3_RX

MFX_USART3_TX

MFX_WAKEUP

MFX_WAKEUP

MFX_IRQ_OUT

MFX_IRQ_OUT

MFX_I2C_SDA

MFX_I2C_SCL

MFX_I2C_SCL
MFX_I2C_SDA

PE10

PE11

PE12
PE13
PE14
PE15

PB6

PE2

PE3

PE4

PE5
PE6

PE7
PE9

PA0

PA1
PA2
PA3

PA4

PA5

PC13
PB10
PB11

PB2
PE8

PD0

PA11
PA12

PC9

SAI1_MCK

AUDIO_RST

SAI1_FS

SAI1_SCK
SAI1_SD

COM0
COM1
COM2
COM3

SEG0
SEG1
SEG2
SEG3
SEG4
SEG5
SEG6
SEG7
SEG8
SEG9
SEG10
SEG11
SEG12

SEG13
SEG14
SEG15
SEG16
SEG17
SEG18
SEG19
SEG20
SEG21
SEG22
SEG23

GYRO_CS

GYRO_INT1

GYRO_INT2

MEMS_SCK

GYRO_CS

MEMS_MISO

MEMS_MOSI

MEMS_SCK

MEMS_MISO

MEMS_MOSI

GYRO_INT1

GYRO_INT2

MAG_CS

MAG_CS

XL_CS

XL_CS
XL_INT

MAG_DRDY

MAG_DRDY

XL_INT

MAG_INT

MAG_INT

PE0
PE1

PC0

PC1

PC2

PD1

PD3

PD4

PD7

PD6

PA6

PA7

PA15

PB0

PB1

PB4
PB5

PB12

PB13

PB14

PB15

PC3

PC4

PC5 PC6

PC7

PC8

PD8PD9

PD10

PD11

PD12

PD13

PD14

PD15

VLCD

AUDIO_DIN
AUDIO_CLK

I2C1_SCL

I2C1_SDA

OTG_FS_OverCurrent

OTG_FS_VBUS

OTG_FS_ID

OTG_FS_DM
OTG_FS_DP

OTG_FS_PowerSwitchOn

VDD_MCU

C76

1uF_X5R_10%_0603

R91

510_1%_0402

L1
Ferrite

C35
100nF_X7R_10%_0402

C74
1uF_POL_10%_TANA

C23
1uF_POL_10%_TANA

C79

1uF_X5R_10%_0603

C82
100nF_X7R_10%_0402
C81
100nF_X7R_10%_0402

C75
100nF_X7R_10%_0402

C29
100nF_X7R_10%_0402

C80
100nF_X7R_10%_0402

VDDA VDDA

R24

47_1%_0402

C24
100nF_X7R_10%_0402

VREF+

VREF+

VDD_MCU

C83
100nF_X7R_10%_0402

R90
0_5%_0402

VDD_MCU

3V

C78

20pF_NPO_5%_0402

C77

20pF_NPO_5%_0402

R89

0_5%_0402

R26

0_5%_0402

R25

0_5%_0402

R88

220_1%_0402

PC14

PH[0..1]

R31

4K7_1%_0402

R32

4K7_1%_0402

3V

R92

2K2_1%_0402

R93

2K2_1%_0402

PC14

PC15

PH1-OSC_OUT

PH0-OSC_IN

PC14-OSC32_IN
PC15-OSC32_OUT

BOOT0

SWO

3V3_REG-ON

3V3_REG-ON

SWOPB3

PB3

Not Fitted

PA8
PA9
PA10
PB9

PD2

PB7

PB8

PC10

PC11

PC12

PA9

PA10

SB24

SB25

Layout priority to PA9, PA10

R87

[NA]

X3
NX3215SA-32.768K

PC15

PC15

C27

4.7pF_NPO_-+0.25pF_0402

C25

4.7pF_NPO_-+0.25pF_0402

UM1879 Schematics

UM1879 Rev 4 27/41

28/41 UM1879 Rev 4

410

IDD measurement / MFX (Multi Function eXpander)

MB1184 C-01

6/15/2015

Title:

Size: R eference:

Date: She et: of

A4

Revision:

STM32L476G-DISCOProject:

VDD_MCU

3V_MFX

Current
direction

to MCU

differential
amplifier

CAL

SH0 SH1 SH2

Shunts

3

4

5

G

SD

6

2

1

T3
STT7P2UH7

3

4

5

G

SD

6

2

1

T7
STT7P2UH7

3

4

5

G

SD

6

2

1

T9
STT7P2UH7

3

4

5

G

SD

621

T5
STT7P2UH7

3V3

decoupling capacitors
close to TSZ122

MFX_IRQ_OUT

IDD_MEAS

MFX_SWCLK

CAL

SH2

SH1

MFX_SWDIO

IDD_MEAS

see note *

SH1_D SH2_DSH0_D

CAL_D

435

G

SD

6
7
8

2

1T2

STS9P2UH7

3V_MFX

SH0_D

SH0

435

G

SD

6
7
8

2

1T4

STS9P2UH7

3V_MFX

CAL_D

CAL

435

G

SD

6
7
8

2

1T6

STS9P2UH7

SH1_D

SH1

435

G

SD

6
7
8

2

1T8

STS9P2UH7

SH2_D

SH2

CAL_D

CAL_D

3V

3V_MFX

one capacitor close to each MFX pins:

SH0

VDD_MCU

MFX_WAKEUP

L2

Ferrite

MFX_I2C_SDA

MFX_I2C_SCL

123

JP5

bypass

R36

100K_1%_0402

R37
100K_1%_0402

R39
1_1%_0805

R43
24_1%_0805

R44
620_1%_0805

R41
10K_1%_0805

R34

100K_1%_0402

R29

10K_1%_0402

C33
100nF_X7R_10%_0402

C341uF_POL_10%_TANA

C26
100nF_X7R_10%_0402

R38

100K_1%_0402

R94

100K_1%_0402

MFX_USART3_RX

MFX_USART3_TX

MFX_USART3_RX

MFX_USART3_TX

3V_MFX

1
2
3
4

CN5

MFX_SWCLK

MFX_SWDIO

C30
100nF_X7R_10%_0402

C31

100nF_X7R_10%_0402
C28
100nF_X7R_10%_0402

C37
100nF_X7R_10%_0402

C40
1uF_X5R_10%_0603

R51

100_1%_0402

C39
100nF_X7R_10%_0402

V+

V-

3

2

1

4 8

U11A
TSZ122IST

5

6

7

U11B
TSZ122IST

V+

V-

3

2

1

4 8

U10A
TSZ122IST

5

6

7

U10B
TSZ122IST

C36

100nF_X7R_10%_0402

see note *

see note *

see note *

Note *: two footprints superimposed allows to
also populate with SO-8 package.
(STS9P2UH7 P MOS transistors)

LAYOUT PROPOSAL DRAWING

C38

100nF_X7R_10%_0402

3V3

decoupling capacitors
close to TSZ122

R27
0_5%_0402

MFX_I2C_SCL
MFX_I2C_SDA

MFX_WAKEUP

MFX_IRQ_OUT

R28

510_1%_0402

R35

[NA]

NRST

C32
[NA]

NRST

MFX_I2C_SCL

MFX_I2C_SDA

R30
0_5%_0603

3V_MFX

3V_MFX

3V_MFX

3V_MFX

PC13

PB10

PA4

PB11

SB27

SB26

D5 BAT60JFILM

VDD

1

WAKEUP

2

IDD_CAL/GPO4

3

IDD_SH0

4

IDD_SH1/GPO5

5

IDD_SH2/GPO6

6

NRST

7

VSSA

8

VDDA

9

TSC_XP/GPO0

10

TSC_XN/GPO1

11

TSC_YP/GPO2

12

TSC_YN/GPO3

13

IDD_MEAS

14

GPIO0

18

GPIO1

19

GPIO2

20

GPIO3

39

GPIO4

40

GPIO5

15

USART_TX

21

USART_RX

22

VSS_1

23

VDD_1

24

SPARE

25

GPIO6

16

GPIO7

17

GPIO8

29

GPIO9

30

GPIO10

31

GPIO11

32

GPIO12

33

GPIO13

26

SWDIO

34

VSS_2

35

VDD_2

36

SWCLK

37

IDD_SH3/GPO7

38

GPIO14

27

GPIO15

28

IDD_VDD_MCU

41

I2C_SCL

42

I2C_SDA

43

BOOT0

44

I2C_ADDR

45

IRQOUT

46

VSS_3

47

VDD_3

48

W

A

KEUP

_

G

O

IDD

S

H

0

IDD_SH

GPO

5

IDD_SH

2/GPO

6

N

S

T

TS

C

_

P/GP

O

0

TS

C

_X

N

/GPO

1

TS

C

Y

/G

O

TS

C

_Y

N

/G

O

3

IDD

A

S

G

P

I

O

0

GPO

G

P

IO2

G

I

O

3

G

IO4

GPO

5

U

S

A

R

T_TX

U

S

T_R

P

I

P

I

P

I

P

I

P

IWD

I

W

G

P

I

P

I

IDD_VD

D

_MC

U

I

2C

_S

L

I

2C

S

D

A

B

0

I

2C

A

DDR

U

MFX_V2

U8
MFX_V2

R47

6K04_1%_0402

R40

6K04_1%_0402

R49

15K_1%_0402

R42

300K_1%_0402

R50

300K_1%_0402

R48
300K_1%_0402

Figure 13. IDD measurement / MFX (Multi Function eXpander)

Schematics UM1879

X

_

T

O

R

_
_

P
P

1

_

1/

D_SH3/

C

L/

_ME

VDD, VDD 1, VDD 2, VDD 3

Figure 14. Joystick ACP, LEDs and push-button

510

Joystick, ACP, LEDs and Push Button

MB1184 C-01

6/15/2015

Title:

Size: Reference:

Date: Sheet: of

A4

Revision:

STM32L476G-DISCOProject:

USER & WAKE-UP Button

NRST

NRST

RESET Button

3V

12

3 4

B1

SW-PUSH-CMS_BLACK

SB23

C45

100nF

LD_R

LD_G

LD_R

LD_G

LD4

LED, red

LD5

LED, green

PB2

PE8

3V

JOY_CENTER

JOY_DOWN

JOY_LEFT

JOY_RIGHT
JOY_UP

PA0

Input pins with pull-dow n

C41
100nF_X7R_10%_0402

R52

0_5%_0402

R53

100_1%_0402

COMMON

5

CENTER

2

DOWN

3

LEFT

1

RIGHT

6

UP

4

6

2

1

4

3

B2

MT-008A

C44
100nF_X7R_10%_0402

C46
100nF_X7R_10%_0402

C42
100nF_X7R_10%_0402

R56

0_5%_0402

R58

0_5%_0402

R54

0_5%_0402

1 2
3 4
5 6
7 8

CN2

SSM-104-L-DH

3V

EXT/RF E2P Connector

5V

EXT_RST

I2C1_SDA
I2C1_SCL

EXT_RSTI2C1_SCL

I2C1_SDA

PA1

PA2
PA3

PA5

R55

10K_1%_0402

R59
10K_1%_0402

Joystick

JOY_CENTER

JOY_DOWN

JOY_LEFT

JOY_RIGHT
JOY_UP

C43
100nF_X7R_10%_0402

PD0PB6

R45

1K_1%_0402

R57
10K_1%_0402

R46

330_1%_0402

Not Fitted

SB2

PB7

UM1879 Schematics

UM1879 Rev 4 29/41

610

LCD Display

MB1184 C-01

6/15/2015

Title:

Size: Reference:

Date: Shee t: of

A4

Revision:

STM32L476G-DISCOPr ojec t:

LCD

SEG[0..23]
COM[0..3]

SEG0

SEG1

SEG2

SEG3

SEG4

SEG5

SEG6 SEG7

SEG8

SEG9

SEG10

SEG11

SEG12

SEG13

SEG14

SEG15

SEG16SEG17

SEG18

SEG19

SEG20

SEG21

SEG22

SEG23

COM0

COM1

COM2

COM3

SEG[0..23]
COM[0..3]

SEG01SEG12SEG23SEG34SEG45SEG56SEG67SEG78SEG89SEG910SEG1011SEG1112COM313COM2

14

COM115COM0

16

SEG1217SEG1318SEG1419SEG1520SEG1621SEG1722SEG1823SEG1924SEG2025SEG2126SEG2227SEG23

28

U5
GH08172T

U100

Socket DIP28

30/41 UM1879 Rev 4

Figure 15. LCD display

Schematics UM1879

UM1879 Rev 4 31/41

710

OTG USB FS

MB1184 C-01

6/15/2015

Title:

Size: Reference:

Date: Sheet: of

A4

Revision:

STM32L476G-DISCOProject:

5V

OTG_FS_PowerSwitchOn

OTG_FS_OverC urrent

3V3_REG

OTG_FS_DM
OTG_FS_DP
OTG_FS_ID

PC9

PC10

PC11

R67 22
R68 22

3V3_REG

3V3_REG

Dz

A2

ID

A3

Pd1

B1

Pup

B2

Vbus

B3

D+in

C1

Pd2

C2

D+out

C3

D-in

D1

GND

D2

D-out

D3

U15

EMIF02-USB03F2

GND

2

IN

5

EN

4

OUT

1

FAULT

3

U14

STMPS2141STR

OTG_FS_VBUS

C67

4.7uF

3

1

2

T10
9013-SOT23

R63

[NA]

R71
330_1%_0603

R65

47K_1%_0402

LD6
LED, green

VBUS

1

DM

2

DP

3

ID

4

GND

5

Shield

6

USB_Micr o-AB receptac le

CN7

USB-MICRO-AB

R72

47K_1%_0402

R66

0_5%_0402

LD7
LED, red

R61

0_5%_0402

R64

0_5%_0402

R62

10K_1%_0402

PC12

PA11
PA12

R73
620_1%_0603

Figure 16. OTG USB FS

UM1879 Schematics

32/41 UM1879 Rev 4

810

Audio Cod ec and Microphone MEMS

MB1184 C-01

6/15/2015

Title:

Size: Reference:

Date: Sheet: o f

A4

Revision:

STM32L476G-DISCOProject:

SAI1_FS

SAI1_SD

SAI1_SCK

I2C1_SCL

I2C1_SDA

AUDIO_RST

SAI1_MCK

3V

I2C address 0x94

2V5

3V

PE3

PB7
PB6

PE2

1

3

2

CN6

ST-225-02

I2C1_SCL

I2C1_SDA

SAI1_MCK
SAI1_SCK
SAI1_SD
SAI1_FS
AUDIO_RST

SDA

1

SCL

2

A0

3

SPKR_OUTA+

4

VP

5

SPKR_OUTA-

6

SPKR_OUTB+

7

VP

8

SPKR_OUTB-

9

-VHPFILT

10

FLYN

11

FLYP

12

+VHP

13

HP/LINE_OUTB

14

HP/LINE_OUTA

15

VA

16

AGND

17

FILT+

18

VQ

19

TSTO

20

AIN4A

21

AIN4B

22

AIN3A

23

AIN3B

24

AIN2A

25

AIN2B

26

AFILTA

27

AFILTB

28

AIN1A

29

AIN1B

30

SPKR/HP

31

RESET

32

VL

33

VD

34

DGND

35

TSTO

36

MCLK

37

SCLK

38

SDIN

39

LRCK

40

GND/Thermal Pad

41

U13

CS43L22

C68

1uF_POL_10%_TANA
C65
100nF_X7R_10%_0402

R60

10K_1%_0402
C56
1uF_X5R_10%_0603

C66
1uF_X5R_10%_0603

C59
150pF_NPO_5%_0603

C58
100nF_X7R_10%_0402

C64

22nF_X7R_10%_0603

PE4

PE5
PE6

C53
150pF_NPO_5%_0603

C60
1uF_X5R_10%_0603

C50
100nF_X7R_10%_0402

C62
100nF_X7R_10%_0402
C51
100nF_X7R_10%_0402

C57

1uF_X5R_10%_0603

C52

100nF_X7R_10%_0402

R70
51_1%_0402

C63

22nF_X7R_10%_0603

R69
51_1%_0402

R76

0_5%_0402

3V

PE9
PE7

3V

AUDIO_DIN

AUDIO_CLK

AUDIO_DIN

AUDIO_CLK

C70
100nF_X7R_10%_0402

C69
100nF_X7R_10%_0402

R77

0_5%_0402

R75

[NA]

GND

5

LR

2

CLK

3

VDD

1

DOUT

4

U17

MP34DT01

GND

Figure 17. Audio DAC and microphone MEMS

Schematics UM1879

UM1879 Rev 4 33/41

910

Quad SPI Flash Memory

MB1184 C-01

6/15/2015

Title:

Size: Reference:

Date: Sheet: of

A4

Revision:

STM32L476G-DISCOProject:

3V

Quad SPI Flash Memory

QSPI_D0

QSPI_D3

QSPI_D2

QSPI_D1

QSPI_CLK

QSPI_CS

PE10

R74

10K_1%_0402

C61
100nF_X7R_10%_0402

DQ3/HOLD#

7

VCC

8

S#

1

DQ1

2

C

6

DQ0

5

VSS

4

DQ2/Vpp/W#

3

D

H

LD

#

V

#

D

D

V

D

2/V

pp/W

#

U16

N25Q128A13EF840E

QSPI_D0
QSPI_D1
QSPI_D2
QSPI_D3

QSPI_CS
QSPI_CLK

PE11

PE12
PE13
PE14
PE15

Figure 18. Quad-SPI Flash memory

/

UM1879 Schematics

34/41 UM1879 Rev 4

10 10

Gyroscope, Accelerometer, Magnetometer MEMS

MB1184 C-01

6/15/2015

Title:

Size: Reference:

Date: Sheet: of

A4

Revision:

STM32L476G-DISCOProject:

MEMS

3V

GYRO_CS

VDD_IO

1

GND

13

C1

14

GND

8

GND

9

VDD

16

CS_I2C/SPI

5

INT1

7

DRDY/INT2

6

GND

10

GND

11

SA0/SDO

4

SDA/SDI/SDO

3

SCL/SPC

2

VDD

15

GND

12

U7

L3GD20

C18
10uF_X5R_10%_0603

C20
10nF_X7R_10%_0603

C19
100nF_X7R_10%_0402

SCL/SPC1INT_XL

12

VDD

9

VDD_IO

10

DRDY_MAG

11

GND

6

C1

5

SDA/SDI/SDO

4

GND

8

INT_MAG

7

CS_MAG

3

CS_XL

2

U6

LSM303CTR

C16
100nF_X7R_10%_0402

C21
10uF_X5R_10%_0603

C17
100nF_X7R_10%_0402

C22
100nF_X7R_10%_0402

MAG_CS

MAG_INT

XL_INT

PC0 MAG_CS

MAG_INT

GYRO_INT1

MAG_DRDY

MEMS_SCK

MAG_DRDY

PC1

PC2

MEMS_MOSI

GYRO_INT2

XL_CS

XL_INT

PD1

PD4

PD7

PD2

PB8

PE0

PE1

MEMS_SCK

GYRO_CS

MEMS_MISO

MEMS_MOSI

PD1

PD3

PD4

MEMS_SCK

MEMS_MISO

MEMS_MOSI

GYRO_INT1

GYRO_INT2

XL_CS

3V

R23 1K_1%_0402

Figure 19. Gyroscope, accelerometer, magnetometer MEMS

Schematics UM1879

3V3_REG

JP6

Measured 287µA

3V3

287-115 => 172µA 172-92 => 80µA

Measured 115 µA

D6

3V

Measured 92µA

LDO

/'

SB28

For IDD
TSZ122

1st stage

V+ : ~11µA due to resistors bridge
V- : ~11µA due to resistors bridge

115-70 => 45µA

Measured 70µA

R30

Audio

03

QuadSPI

14

L3GD20

DAC&6

LSM303

CTR

3V_MFX

70-0.4 => 69.6µA

Measured 0.4µA

JP5

VDD_MCU

MFX

STM32L152

For IDD

TSZ122

2nd stage

V+ : ~10µA due to resistors bridge

STM32L476VGT6

PWR->PUCRA = 0; // no PU on GPIOA
PWR->PDCRA = 0x2F; // PD on GPIOA[0,1,2,3,5]
PWR->PUCRB = 0; // no PU on GPIOB
PWR->PDCRB = 0; // no PD on GPIOB
PWR->PUCRC = 0x1; // PU on GPIOC[0] MAG_CS
PWR->PDCRC = 0x800; // PD on GPIOC[11]
PWR->PUCRD = 0x80; // PU on GPIOD[7] MEMS_SPI_CS
PWR->PDCRD = 0x12; // no PD on GPIOD[1,4] MEMS_SPI_CLK, MEMS_SPI_MOSI
PWR->PUCRE = 0x0001; // PU on GPIOE[0] XL_CS
PWR->PDCRE = 0x0200; // PD on GPIOE[9] AUDIO_CLK for DMIC
PWR->PDCRE|= 0x0074; // PD on GPIOE[2,4,5,6] SAI1 interface to CODEC
PWR->PDCRE|= 0xF400; // PD on GPIOE[10,12,13,14,15] QuadSPI CLK, D0,D1,D2,D3
PWR->PUCRF = 0; // no PU on GPIOF
PWR->PDCRF = 0; // no PD on GPIOF
PWR->PUCRG = 0; // no PU on GPIOG
PWR->PDCRG = 0; // no PD on GPIOG
PWR->PUCRH = 0; // no PU on GPIOH
PWR->PDCRH = 0; // no PD on GPIOH

UM1879 Power consumption measurements

Appendix A Power consumption measurements

The power consumption measurements of the STM32L476 Discovery board are reflected in

Figure 20. Note the GPIO configuration of the STM32L476VGT6 in standby mode.

Figure 20. Power consumption tree

STM32L476VGT6 GPIOs are configured in ‘Analog input’ except:

UM1879 Rev 4 35/41

40

Power consumption measurements UM1879

The total measured power consumption of the STM32L476 Discovery board is 287 µA,
which is as expected.

Tab le 9 gives for each peripheral the theoretical power consumption value. It is extracted

from the vendor’s product datasheet. The typical values are given under the same
conditions as used for the power consumption measurement (see

Figure 20: Power

consumption tree). Refer to those product datasheets for more details about the conditions.

The theoretical total power consumption of the STM32L476 Discovery board is ~295 µA.

Table 9. Typical power consumption of the STM32L476 Discovery board

MB1184-C01

component

LD3985M25R_U12 85 On mode: VINH = 1.2 V

TSZ122IST_U10 58 -

Differential + 11 Current in R40 + R42

Differential - 11 Current in R47 + R50

CS43L22_U13 0 Reset pin 32 and all clocks and lines are hold Low

MP34DT01_U17 33 IddPdn, input clock in static mode

N25Q128A13EF840E_U16 14 Standby current

L3GD20_U7 5 IddPdn, Supply current in power-down mode

LSM303CTR_U6 10 IddPdn, current consumption in power-down mode

TSZ122IST_U11 58 -

Bridge Op Amp 10 Current in R48 + R49

MFX_U8 0.3

STM32L476VGT6_U9 0.3

Typ ica l

theoretical

consumption

(µA)

Conditions

Standby mode. All GPIOs in ‘Analog Input’ except
WAKEUP input with external PD (R34)

Standby mode, GPIOs configuration described
above

TOTAL STM32L476

Discovery board

36/41 UM1879 Rev 4

295.6 -

UM1879 Mechanical drawing

Appendix B Mechanical drawing

Figure 21. STM32L476 Discovery board mechanical drawing

UM1879 Rev 4 37/41

40

Compliance statements UM1879

Appendix C Compliance statements

C.1 FCC Compliance Statement

C.1.1 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.

C.1.2 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 instructions, 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 the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and the 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.

C.1.3 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.

C.2 IC Compliance Statement

This device complies with FCC and Industry Canada RF radiation exposure limits set forth
for general population for mobile application (uncontrolled exposure). This device must not
be collocated or operating in conjunction with any other antenna or transmitter.

C.2.1 Compliance Statement

Notice: This device complies with Industry Canada licence-exempt RSS standard(s).
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must accept any interference, including interference that
may cause undesired operation of the device.

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

38/41 UM1879 Rev 4

UM1879 Compliance statements

C.2.2 Déclaration de conformité

Avis: Le présent appareil est conforme aux CNR d'Industrie Canada applicables aux
appareils radio exempts de licence. L'exploitation est autorisée aux deux conditions
suivantes : (1) l'appareil ne doit pas produire de brouillage, et (2) l'utilisateur de l'appareil
doit accepter tout brouillage radioélectrique subi, même si le brouillage est susceptible d'en
compromettre le fonctionnement.

Etiquette de conformité à la NMB-003 d'Industrie Canada: : CAN ICES-3 (B) / NMB-3 (B).

UM1879 Rev 4 39/41

40

Revision history UM1879

Revision history

Date Revision Changes

17-Jul-2015 1 Initial release.

04-Aug-2015 2 Added Section 6: Bootloader limitations.

24-Mar-2016 3 Added Section Appendix C: Compliance statements.

27-Jun-2018 4

Table 10. Document revision history

Updated Table 8: Solder bridges. Updated Chapter 6:

Ordering information. Updated Section 10.1.1: Drivers.

Updated Appendix C: Compliance statements. Added

Chapter 2: Product marking, Chapter 3: System
requirements, and Chapter 4: Development toolchains.

40/41 UM1879 Rev 4

UM1879

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UM1879 Rev 4 41/41

41