UM2140 Rev 3
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UM2140
Hardware layout and configuration
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1.
Connect the CN8 jumper on E5V or USB_HS or USB_FS.
2. Connect the external power source to CN3, or CN12, or CN18, or CN19.
3. Check that the LD2 red LED is turned ON.
4. Connect the PC to the CN1 USB connector.
If this order is not respected, the 32F723EDISCOVERY Discovery board may be powered by
V
BUS
first from ST-LINK and the following risks may be encountered:
1.
If more than 500 mA current is needed by the board, the PC may be damaged or the
current can be limited by the PC. As a consequence, the board is not powered correctly.
2. 500 mA is requested at the enumeration: if the PC cannot provide such a current, there
is a risk that the request is rejected and the enumeration does not succeed.
5.6 Clock
sources
Up to 2 clock sources as described below:
•
X2 25 MHz oscillator for STM32F723IEK6 microcontroller
•
X3 32 KHz crystal for the STM32F723IEK6 embedded RTC
5.7 Reset
sources
The reset signal of the 32F723EDISCOVERY board is active LOW and the reset sources
include:
•
Reset button B2
•
ARDUINO
®
Uno V3 shield board from CN12
•
Embedded ST-LINK/V2-1
5.8 Audio
An audio codec with 4 DACs and 2ADCs is connected to the SAI interface of
STM32F723IEK6. It communicates with STM32F723IEK6 via I
2
C bus:
•
The analog line input is connected to the audio codec ADC through the CN4 blue audio
jack.
•
The analog line output is connected to the audio codec DAC via the CN5 green audio
jack.
•
Two external speakers can be connected to the audio codec via CN10 for the left
speaker and CN7 for the right speaker.
•
Four digital ST-MEMS microphones are on the 32F723EDISCOVERY board. They are
connected to the digital microphone inputs of the audio codec.
