ST STM32H745I-DISCO

• Ethernet
6.7 Audio
An audio Codec WM8994ECS/R from CIRRUS with four DACs and two ADCs is connected to the
STM32H745XIH6 and STM32H750XBH6 SAI interface. It communicates with the STM32H745XIH6 and
STM32H750XBH6 microcontrollers via an I
2
C bus shared with the touchpanel of the RGB LCD, ARDUINO
®
and
STMod+ connectors.
• The analog input line is connected to the WM8994ECS/R ADC through the blue audio jack (CN8).
• The analog output line is connected to the WM8994ECS/R DAC via the green audio jack (CN9).
• Two external speakers can be connected to WM8994ECS/R via CN18 for left speaker and CN17 for right
speaker.
• The STM32H745I-DISCO and STM32H750B-DK feature one digital MP34DT01TR microphones (ST MEMs
microphone). They are connected to the input digital microphones of the STM32H745XIH6/
STM32H750XBH6 and are managed by the PDM functionality.
6.8 USB OTG_FS
The STM32H745I-DISCO and STM32H750B-DK boards support USB OTG full-speed communications via the
CN13 USB Micro-AB connector.
The USB connectors can power the Discovery kit with a 5 V DC supply voltage, at a current up to 500 mA.
A USB power switch is also connected to VBUS and provides power to CN13. The green LED LD1 is lit when
either one of the following event occurs:
• The power switch is ON and the STM32H745I-DISCO/STM32H750B-DK operate as a USB host.
• VBUS is powered by another USB host when the STM32H745I-DISCO/STM32H750B-DK operate as a USB
device.
The red LED LD5 is lit when an overcurrent occurs.
Note: The STM32H745I-DISCO and STM32H750B-DK boards must be powered by external power supply when using
the OTG function.
6.9 eMMC
The STM32H745I-DISCO and STM32H750B-DK embed a 4-Gbyte eMMC chip. It is connected to the
STM32H745XIH6 and STM32H750XBH6 SDMMC1 port.
6.10 Ethernet
The STM32H745I-DISCO and STM32H750B-DK boards support 10M/100M Ethernet communications by a
MICROCHIP LAN8740Ai-EN-TR PHY, which supports IEEE 802.3az Energy Efficient Ethernet (EEE) and
integrated RJ45 connector CN1. The Ethernet PHY is connected to the STM32H745XIH6/STM32H750XBH6
microcontroller through an MII interface.
The PHY 25 MHz clock is generated from the X1 oscillator, while the STM32H745XIH6/STM32H750XBH6
50 MHz clock is generated by the PHY MII_REF_CLK.
6.11
Power over Ethernet
The STM32H745I-DISCO and STM32H750B-DK Discovery boards embed a power module that uses Ethernet.
This module is an IEEE802.3af compliant class 1 / 2 PoE converter, based on a simple diode rectified Flyback
topology built around ST PM8800A component. This “powered device” module accepts a 48 V input voltage and
can deliver 5 V with 600 mA.
6.12 SDRAM
A 128-Mbit SDRAM (MT48LC4M32B2B5-6A IT_L TR from MICRON) is connected to the STM32H745XIH6/
STM32H750XBH6 FMC interface.
UM2488
Audio
UM2488 - Rev 4
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