Hardware
UM2042
6/25
DocID029132 Rev 3
2 Hardware
The PCB (Printed Circuit Board) is connected via USB to the PC. The STSW-ST25R001 PC
software controls the STM32 MCU located on the PCB. The STM32 MCU (based on Arm
®
core) then operates the ST25R3911B via SPI.
The ST25R3911B is connected directly to the 5 V supply of the USB bus. An LDO converts
this voltage down to 3.3 V, to supply the microcontroller.
A green LED close to the USB plug indicates if the board is powered. Six blue LEDs indicate
the mode of operation (transmit / receive) and which technologies are in use.
The antenna runs along the PCB perimeter.
2.1 Block
diagram
Figure 2
shows the functional block diagram of the board.
Figure 2. Functional block diagram
2.2 Schematics
As indicated in
Figure 3
, the schematics can be split into four main parts
•
USB connectivity and power supply (
Figure 4
)
•
STM32 MCU (
Figure 5
)
•
ST25R3911B (
Figure 6
)
•
Antenna and matching network components (
Figure 7
)
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Summary of Contents for ST25R3911B
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Page 19: ...UM2042 Hardware DocID029132 Rev 3 19 25 Figure 12 PCB layout bottom layer ...
