ST STM32F746G-DISCO User manual

March 2016 DocID027942 Rev 3 1/49
1
UM1907
User manual
Discovery kit for STM32F7 Series with STM32F746NG MCU
Introduction
The STM32F746G-DISCO discovery board (32F746GDISCOVERY) is a complete
demonstration and development platform for STMicroelectronics ARM®Cortex®-M7 core-
based STM32F746NGH6 microcontroller. This microcontroller features four I2Cs, six SPIs
with three multiplexed simplex I2S, SDMMC, four USARTs, four UARTs, two CANs, three
12-bit ADCs, two 12-bit DACs, two SAIs, 8- to 14-bit digital camera module interface,
internal 320+16+4-Kbyte SRAM and 1-Mbyte Flash memory, USB HS OTG, USB FS OTG,
Ethernet MAC, FMC interface, Quad-SPI interface, SWD debugging support. This discovery
board offers everything required for users to get started quickly and develop applications
easily.
The full range of hardware features on the board helps users to evaluate almost all
peripherals (USB OTG HS, USB OTG FS, 10/100-Mbit Ethernet, microSD™card, USART,
SAI Audio DAC stereo with audio jack input and output, MEMS digital microphones,
SDRAM, Quad-SPI Flash memory, 4.3-inch color LCD-TFT with a capacitive multi-touch
panel, SPDIF RCA input, etc.) and to develop their applications. Arduino™Uno V3
connectors make it possible to easily connect extension shields or a daughterboard for
users’ specific applications. The integrated ST-LINK/V2-1 provides an embedded in-circuit
debugger and programmer for the STM32.
The STM32F746G-DISCO board comes with the STM32 comprehensive software HAL
library together with various packaged software examples, as well as a direct access
to ARM®mbed™online resources at http://mbed.org.
Figure 1. STM32F746G-DISCO board (top view)
Figure 2. STM32F746G-DISCO board (bottom view)
1. Pictures not contractual.
www.st.com

Contents UM1907
2/49 DocID027942 Rev 3
Contents
1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 Demonstration software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 Product marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4 Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5 Technology partners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
6 Hardware layout and configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.1 Embedded ST-LINK/V2-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
6.1.1 Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6.1.2 ST-LINK/V2-1 firmware upgrade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.2 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.3 Programming/debugging when the power supply is not from
ST-LINK (5V link) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.4 Clock sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.5 Reset sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.6 Audio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.7 USB OTG FS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.8 USB OTG HS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.9 microSD card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.10 Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.11 SDRAM memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.12 Quad-SPI Nor Flash memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.13 Camera module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.14 Display LCD-TFT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7 Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7.1 I2C extension connector CN2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7.2 Camera module connector P1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7.3 Arduino Uno V3 connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

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7.4 USB OTG HS micro-AB connector CN12 . . . . . . . . . . . . . . . . . . . . . . . . 22
7.5 Ethernet RJ45 connector CN9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
7.6 USB OTG FS micro-AB connector CN13 . . . . . . . . . . . . . . . . . . . . . . . . . 23
7.7 microSD connector CN3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
7.8 ST-LINK/V2-1 USB type B connector CN14 . . . . . . . . . . . . . . . . . . . . . . . 24
7.9 Audio stereo speakers JP3 and JP4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.10 Audio green jack (line Out) CN10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.11 Audio blue jack (line In) CN11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.12 SPDIF input RCA connector CN1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
8 Electrical schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Appendix A STM32F746G-DISCO IO assignment . . . . . . . . . . . . . . . . . . . . . . . . 39
Appendix B Mechanical drawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Appendix C Compliance Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
C.1 Federal Communications Commission (FCC) and Industry
Canada (IC) Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
C.1.1 FCC Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
C.2 IC Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
C.2.1 Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
C.2.2 Déclaration de conformité. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

List of tables UM1907
4/49 DocID027942 Rev 3
List of tables
Table 1. I2C extension connector CN2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 2. Camera module connector P1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 3. Arduino connectors (CN4, CN5, CN6, CN7). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Table 4. USB OTG HS micro-AB CN12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Table 5. RJ45 connector CN9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 6. USB OTG FS micro-AB connector CN13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 7. microSD connector CN3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 8. USB type B connector CN14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 9. SPDIF input RCA connector CN1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 10. STM32F746G-DISCO IO assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Table 11. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

DocID027942 Rev 3 5/49
UM1907 List of figures
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List of figures
Figure 1. STM32F746G-DISCO board (top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 2. STM32F746G-DISCO board (bottom view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 3. Hardware block diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 4. STM32F746G-DISCO discovery board top layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 5. STM32F746G-DISCO discovery board bottom layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 6. USB composite device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 7. JP1 (5V ext) from JP2 (5V). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 8. JP1 (5V ext) from CN6 (Vin) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 9. JP1 (5V link) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 10. JP1 (usb_fs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 11. JP1 (usb_hs). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 12. Inside RJ45 jack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 13. I2C extension connector CN2 (front view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 14. Camera module connector P1 (front view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 15. USB OTG micro-AB connector CN12 (front view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 16. Ethernet RJ45 connector CN9 (front view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 17. USB OTG micro-AB connector CN13 (front view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 18. microSD connector CN3 (front view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 19. USB type B connector CN14 (front view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 20. STM32F746 discovery interconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Figure 21. ST-LINK/V2-1 with support of SWD only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 22. Joystick, LEDs and pushbutton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 23. Audio codec Cirrus and connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Figure 24. Quad-SPI Flash memory (MICRON) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Figure 25. Arduino Uno connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 26. SDRAM (MICRON). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Figure 27. USB OTG FS with micro A-B connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Figure 28. STM32F746NGH6 connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 29. USB OTG HS PHY with micro A-B connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 30. Ethernet PHY with RJ45 connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Figure 31. External camera connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Figure 32. 4.3-inch LCD with capacitive touch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Figure 33. Mechanical drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Features UM1907
6/49 DocID027942 Rev 3
1 Features
•STM32F746NGH6 microcontroller featuring 1 Mbyte of Flash memory and
340 Kbytes of RAM, in BGA216 package
•On-board ST-LINK/V2-1 supporting USB reenumeration capability
•ARM®mbed™-enabled (see http://mbed.org)
•USB functions: virtual COM port, mass storage, debug port
•4.3-inch 480x272 color LCD-TFT with capacitive touch screen
•Camera connector
•SAI audio codec
•Audio line in and line out jack
•Stereo speaker outputs
•Two ST MEMS microphones
•SPDIF RCA input connector
•Two push buttons (user and reset)
•128-Mbit Quad-SPI Flash memory
•128-Mbit SDRAM (64-Mbit accessible)
•Connector for microSD card
•RF-EEPROM daughterboard connector
•USB OTG HS with Micro-AB connectors
•USB OTG FS with Micro-AB connectors
•Ethernet connector compliant with IEEE-802.3-2002
•Five power supply options:
–STLINK/V2-1
– USB FS connector
– USB HS connector
– VIN from Arduino connector
– External 5 V from connector
•Power supply output for external applications: 3.3 V or 5 V
•Arduino Uno V3 connectors
•Comprehensive free software including a variety of examples, part of STM32Cube
package
•Supported by a wide choice of integrated development environments
2 Demonstration software
The demonstration software is preloaded in the STM32F746NGH6 Flash memory. The
latest versions of the demonstration source code and associated documentation can be
downloaded from www.st.com/stm32f7-discovery.

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UM1907 Product marking
48
3 Product marking
Evaluation tools marked as "ES" or "E" are not yet qualified and therefore they are 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 section “Package characteristics” of the STM32 datasheet at www.st.com).
•Next to the evaluation tool ordering part number, that is stuck or silk-screen printed on
the board.
4 Ordering information
To order the discovery kit with STM32F746NG MCU, use the order code:
STM32F746G-DISCO.
5 Technology partners
MICRON:
•128-Mbit SDRAM (64 Mbit accessible on the kit), part number MT48LC4M32B2
•128-Mbit Quad-SPI NOR Flash memory device, part number N25Q128A
ROCKTECH:
•Color display, 4.3-inch LCD-TFT (resolution: 480x272), capacitive touch,
part number RK043FN48H-CT672B

Hardware layout and configuration UM1907
8/49 DocID027942 Rev 3
6 Hardware layout and configuration
STM32F746G-DISCO discovery board is designed around the STM32F746NGH6 (216-pin
TFBGA package). The hardware block diagram (see Figure 3) illustrates the connection
between STM32F746NGH6 and peripherals (SDRAM, Quad-SPI Flash memory, camera
module, color LCD, USB OTG connectors, USART, Ethernet, Audio, SPDIFRX, microSD
card, Arduino Uno shields and embedded ST-LINK) and Figure 4 will help to locate these
features on the actual discovery board.
Figure 3. Hardware block diagram
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UM1907 Hardware layout and configuration
48
Figure 4. STM32F746G-DISCO discovery board top layout
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Hardware layout and configuration UM1907
10/49 DocID027942 Rev 3
Figure 5. STM32F746G-DISCO discovery board bottom layout
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48
6.1 Embedded ST-LINK/V2-1
The ST-LINK/V2-1 programming and debugging tool is integrated on the
STM32F746G-DISCO discovery board. Compared to ST-LINK/V2 the changes are listed
below.
The new features supported on ST-LINK/V2-1 are:
•USB software reenumeration
•Virtual Com port interface on USB
•Mass storage interface on USB
•USB power management request for more than 100 mA 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).
6.1.1 Drivers
The ST-LINK/V2-1 requires a dedicated USB driver, which, for Windows XP, 7 and 8, can be
found at www.st.com.
In case the STM32F746G-DISCO discovery board is connected to the PC before the driver
is installed, some STM32F746G-DISCO 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.
Note: Prefer using the “USB Composite Device” handle for a full recovery.
Figure 6. USB composite device

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6.1.2 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 new functionality, bug fixes, support for new microcontroller families), it is
recommended to visit www.st.com before starting to use the STM32F746G-DISCO board
and periodically, in order to stay up-to-date with the latest firmware version.
6.2 Power supply
The STM32F746G-DISCO discovery board is designed to be powered by 5V DC power
supply. It is possible to configure the discovery board to use any of the following five sources
for the power supply:
•5V DC power adapter connected to JP2 (external power supply on silkscreen of JP1
(5V ext)). In this case, the STM32F746G-DISCO discovery board must be powered by
a power supply unit or by an auxiliary equipment complying with the standard
EN-60950-1: 2006+A11/2009, and must be Safety Extra Low Voltage (SELV) with
limited power capability.
Figure 7. JP1 (5V ext) from JP2 (5V)
•7-12V DC power from CN6 pin named Vin on silkscreen, the extension connectors for
Arduino UNO shields or daughterboard (external power source on silkscreen of JP1
(5V ext)).
Figure 8. JP1 (5V ext) from CN6 (Vin)

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•5V DC power with limitation from CN14, the USB type mini-B connector of
ST-LINK/V2-1 (USB 5V power source on silkscreen of JP1 (5V link)). It is the default
setting. If the USB enumeration succeeds (as explained below), the ST-LINK 5V link
power is enabled, by asserting the PWR_ENn signal. This pin is connected to a power
switch (ST890), which powers the board. This power switch features also a current
limitation to protect the PC in case of a short-circuit on the board (more than 600 mA).
The STM32F746G-DISCO discovery board can be powered from the ST-LINK USB
connector CN14 (5V link), but only the ST-LINK circuit has the power before USB
enumeration, because the host PC only provides 100 mA to the board at that time. During
the USB enumeration, the STM32F746G-DISCO board asks for the 500 mA power to the
host PC. If the host is able to provide the required power, the enumeration ends by a
“SetConfiguration” command and then, the power transistor U8 (ST890) is switched ON, the
red LED LD2 is turned ON, thus the STM32F746G-DISCO board can consume no more
than 500 mA of current. If the host is not able to provide the requested current, the
enumeration fails. Therefore the ST890 (U8) remains OFF and the STM32 part including the
extension board will not be powered. As a consequence the red LED LD2 remains turned
OFF. In this case it is mandatory to use an external power supply.
Figure 9. JP1 (5V link)
Note: In case the board is powered by a USB charger, there is no USB enumeration, so the led
LD2 remains set to OFF permanently and the board is not powered. Only in this specific
case, the resistor R109 needs to be soldered, to allow the board to be powered anyway.
The LED LD2 is lit when the STM32F746G-DISCO discovery board is powered by the 5V
correctly.
Caution: Do not connect the PC to the ST-LINK (CN14) when R109 is soldered. The PC may be
damaged or the board not powered correctly.

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•5V DC power with 500 mA limitation from CN13, the USB OTG FS micro-AB connector
(USB 5V power source on silkscreen of JP1 (usb_fs)).
Figure 10. JP1 (usb_fs)
•5V DC power with 500 mA limitation from CN12, the USB OTG HS micro-AB connector
(USB 5V power source on silkscreen of JP1 (usb_hs)).
Figure 11. JP1 (usb_hs)
6.3 Programming/debugging when the power supply is not from
ST-LINK (5V link)
It is mandatory to power the board first using JP1 (5V ext) or (usb_hs) or (usb_fs), then
connecting the USB cable to the PC. Proceeding this way ensures that the enumeration
succeeds thanks to the external power source.
The following power sequence procedure must be respected:
1. Connect the jumper JP1 on (5V ext) or (usb_hs) or (usb_fs)
2. Connect the external power source to JP2 or CN6 or CN12 or CN13
3. Check the red LED LD2 is turned ON
4. Connect the PC to USB connector CN14
If this order is not respected, the board may be powered by VBUS first from ST-LINK, and
the following risks may be encountered:

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1. If more than 500 mA current is needed by the board, the PC may be damaged or
current can be limited by the PC. As a consequence the board is not powered correctly.
2. 500 mA will be requested at the enumeration, so there is a risk that the request is
rejected and enumeration does not succeed if the PC cannot provide such current.
6.4 Clock sources
Up to 3 clock sources as described below:
•X1, 24 MHz oscillator for the USB OTG HS PHY and camera module (daughterboard)
•X2, 25 MHz oscillator for the STM32F746NGH6 microcontroller and Ethernet PHY
•X3, 32 KHz crystal for the STM32F746NGH6 embedded RTC
6.5 Reset sources
The reset signal of STM32F746G-DISCO discovery board is active low and the reset
sources include:
•Reset button B2
•Arduino Uno shield board from CN6
•Embedded ST-LINK/V2-1
6.6 Audio
An audio codec WM8994ECS/R from CIRRUS with 4 DACs and 2ADCs is connected to SAI
interface of STM32F746NGH6. It communicates with STM32F746NGH6 via I2C bus shared
with the camera module and I2C extension connector.
•The analog line input is connected to ADC of WM8994ECS/R through blue audio jack
CN11.
•The analog line output is connected to DAC of WM8994ECS/R via green audio jack
CN10.
•Two external speakers can be connected to WM8994ECS/R via JP3 for right speaker
and JP4 for left speaker.
•Two digital microphones (ST MEMs microphone) MP34DT01TR are on the
STM32F746G-DISCO discovery board. They are connected to the input digital
microphones of WM8994ECS/R.
•One coaxial connector CN1 is implemented on STM32F746G-DISCO to receive
external audio data compatible with SPDIF specification.

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6.7 USB OTG FS
The STM32F746G-DISCO discovery board supports USB OTG full speed communication
via a USB micro-AB connector (CN13) and USB power switch (U6) connected to VBUS.
The discovery board can be powered by this USB connection at 5V DC with 500mA current
limitation.
A green LED LD5 will be lit in one of these cases:
•Power switch (U6) is ON and STM32F746G-DISCO works as an USB host
•VBUS is powered by another USB host when STM32F746G-DISCO works as an USB
device.
The red LED LD6 will be lit when an overcurrent occurs.
Note: STM32F746G-DISCO board should be powered by an external power supply when using
OTG function.
6.8 USB OTG HS
The STM32F746G-DISCO discovery board supports the USB OTG high speed
communication via a USB micro-AB connector (CN12), USB high speed PHY (U15)
USB3320C-EZK from MICROCHIP for high speed function.
The discovery board can be powered by the USB connectors (CN12) at 5V DC with 500mA
current limitation.
A USB power switch (U7) is also connected on VBUS and provides power to CN12.
The green LED LD4 will be lit in one of these cases:
•Power switch (U17) is ON and STM32F746G-DISCO works as an USB host
•VBUS is powered by another USB host when STM32F746G-DISCO works as an USB
device.
The red LED LD3 will be lit when an overcurrent occurs.
Note: STM32F746G-DISCO board should be powered by an external power supply when using
OTG function.
6.9 microSD card
The 2-Gbyte (or more) microSD card connected to the SDMMC1 port of the
STM32F746NGH6 is supported by the board.

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6.10 Ethernet
The STM32F746G-DISCO discovery board supports 10/100-Mbit Ethernet communication
by a PHY LAN8742A-CZ-TR (U9) from MICROCHIP and RJ45 jack (CN9). Ethernet PHY is
connected to STM32F746NGH6 via RMII interface.
25 MHz clock for the PHY is generated by the oscillator X2, the 50 MHz clock for the
STM32F746NGH6 is generated by the PHY RMII_REF_CLK.
Figure 12. Inside RJ45 jack
6.11 SDRAM memory
128-Mbit SDRAM (MT48LC4M32B2B5-6A from MICRON) is connected to the FMC
interface of the STM32F746NGH6. Only the lowest 16-bit data are used (64-Mbit
accessible). DQ16 to DQ31 are unused and connected to a 10K ohm pull-down resistor.
6.12 Quad-SPI Nor Flash memory
128-Mbit Quad-SPI Nor Flash memory (N25Q128A13EF840E from MICRON) is connected
to the Quad-SPI interface of the STM32F746NGH6.

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6.13 Camera module
A connector P1 with the DCMI signals is available to connect a camera module such as
STM32F4DIS-CAM (ST order code).
6.14 Display LCD-TFT
The color display from ROCKTECH, 4.3-inch 480x272 LCD-TFT with capacitive touch panel
is connected to RGB LCD interface of the STM32F746NGH6.

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7 Connectors
7.1 I2C extension connector CN2
Figure 13. I2C extension connector CN2 (front view)
7.2 Camera module connector P1
Figure 14. Camera module connector P1 (front view)
Table 1. I2C extension connector CN2
Pin number Description Pin number Description
1 I2C_SDA (PB9) 5 +3V3
2NC6NC
3 I2C_SCL (PB8) 7 GND
4 RESET(PC10) 8 NC or 5V
069


Table 2. Camera module connector P1
Pin number Description Pin number Description
1GND16 GND
2 NC 17 DCMI_HSYNC
3NC18 NC
4 DCMI_D0 19 DCMI_VSYNC
5DCMI_D120 3V3

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7.3 Arduino Uno V3 connectors
CN4, CN5, CN6 and CN7 are female connectors compatible with Arduino standard. Most
shields designed for Arduino can fit to the STM32F746G-DISCO discovery board.
The Arduino connectors on STM32F746G-DISCO discovery board support the Arduino Uno
V3.
Caution: The IOs of STM32 microcontroller are 3.3 V compatible instead of 5 V for Arduino Uno.
6 DCMI_D2 21 Camera_CLK (OSC_24M)
7 DCMI_D3 22 NC
8DCMI_D423 GND
9 DCMI_D5 24 NC
10 DCMI_D6 25 DCMI_PWR_EN
11 DCMI_D7 26 DCMI_NRST
12 NC 27 DCMI_SDA
13 NC 28 DCMI_SCL
14 GND 29 GND
15 DCMI_PIXCK 30 3V3
Table 2. Camera module connector P1 (continued)
Pin number Description Pin number Description