ST X-NUCLEO-NFC05A1 NFC User manual

July 2017
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www.st.com
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User manual
Getting started with the X-NUCLEO-NFC05A1 NFC card reader
expansion board based on ST25R3911B for STM32 Nucleo
Introduction
The X-NUCLEO-NFC05A1 NFC card reader expansion board is used to evaluate functions based on
the ST25R3911B, designed for the expansion of STM32 Nucleo boards.
It is compatible with the Arduino™ UNO R3 connector and can be plugged to any STM32 Nucleo board
together with other expansion boards to evaluate different devices.
It features:
On-board NFC card reader IC: ST25R3911B
47 mm x 34 mm, four turns, 13.56 MHz inductive antenna etched on PCB and associated tuning
circuit
Six general purpose LEDs
ISO 18092 (NFCIP-1) active P2P
ISO 14443A and ISO14443B
ISO 15693
FeliCa™
VHBR
6.8 Mbit/s AFE and PCD to PICC framing
3.4 Mbit/s PICC to PCD framing
Up to 1.4 W output power with differential antenna
Possibility of driving two antennas in single ended configuration
Inductive and capacitive wake-up
Automatic antenna tuning system
Transparent and Stream modes to implement MIFARE™ Classic compliant or other custom
protocols

Getting started
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Figure 1: X-NUCLEO-NFC05A1 expansion board

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Contents
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Contents
1Getting started.................................................................................6
1.1 Hardware requirements.....................................................................6
1.2 System requirements........................................................................6
2Board setup .....................................................................................7
3Hardware..........................................................................................8
3.1 Host interface and GPIO connection.................................................9
3.2 X-NUCLEO-NFC05A1 expansion board component placement.....10
4Component description ................................................................11
4.1 ST25R3911B device.......................................................................11
4.2 Schematic diagrams........................................................................11
4.2.1 USB connectivity and power supply................................................. 11
4.2.2 ST25R3911B schematic diagram..................................................... 13
4.2.3 Antenna and matching network components................................... 15
4.3 PCB Layout.....................................................................................17
4.3.1 PCB layers........................................................................................ 17
4.3.2 Top layer........................................................................................... 17
4.3.3 Mid layer 1........................................................................................ 18
4.3.4 Mid layer 2........................................................................................ 18
4.3.5 Bottom layer ..................................................................................... 19
5Bill of materials..............................................................................20
6Federal Communications Commission (FCC) and Industry
Canada (IC) compliance ........................................................................23
6.1 FCC Compliance Statement............................................................23
6.1.1 Part 15.19......................................................................................... 23
6.1.2 Part 15.21......................................................................................... 23
6.1.3 Part 15.105....................................................................................... 23
6.1.4 FCC ID.............................................................................................. 23
6.2 Formal notices required by Industry Canada (“IC”) .........................23
6.2.1 Compliance Statement..................................................................... 23
6.2.2 Declaration de Conformité................................................................ 23
6.2.3 IC ID.................................................................................................. 24
7Revision history ............................................................................25

List of tables
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List of tables
Table 1: Interconnections between the X-NUCLEO-NFC05A1 expansion board and the Nucleo-L476RG
board (left side)...........................................................................................................................................8
Table 2: Interconnections between the X-NUCLEO-NFC05A1 expansion board and the Nucleo-L476RG
board (right side).........................................................................................................................................8
Table 3: Matching variant .........................................................................................................................15
Table 4: X-NUCLEO-NFC05A1 bill of materials.......................................................................................20
Table 5: Document revision history ..........................................................................................................25

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List of figures
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List of figures
Figure 1: X-NUCLEO-NFC05A1 expansion board .....................................................................................2
Figure 2: X-NUCLEO-NFC05A1 component placement ..........................................................................10
Figure 3: STM32 Nucleo connector schematic diagram...........................................................................12
Figure 4: ST25R3911B schematic diagram..............................................................................................14
Figure 5: Matching circuit schematic diagram ..........................................................................................16
Figure 6: PCB layout top layer..................................................................................................................17
Figure 7: PCB layout mid layer 1..............................................................................................................18
Figure 8: PCB layout mid layer 2..............................................................................................................18
Figure 9: PCB layout bottom layer............................................................................................................19

Getting started
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1 Getting started
Connect the X-NUCLEO-NFC05A1 to an STM32 Nucleo-64 development board. The PC
USB port has to be capable of delivering at least 300 mA at 5 V supply. A demo software is
available for download at www.st.com to be programmed onto the STM32 Nucleo.
1.1 Hardware requirements
The X-NUCLEO-NFC05A1 expansion board is designed to be used with any STM32
Nucleo board, although complete testing has been performed using the NUCLEO-L476RG
hosting the STM32L476RG microcontroller.
The STM32 Nucleo firmware and the related documentation are available at
http://www.st.com/stm32nucleo.
1.2 System requirements
To use the STM32 Nucleo boards with the X-NUCLEO-NFC05A1 expansion board the
following software and hardware are required:
an STM32 Nucleo-64 development board
a Windows®PC to install the firmware package
a USB type A to Mini-B USB cable to connect the Nucleo board to the PC
unit must be supplied by a safety extra low voltage (SELV) limited power source
through the USB port, the source should not exceed 60Vdc / 8A / 100VA
To install the board firmware package (order code: X-CUBE-NFC5) the PC must have:
128 MB of RAM
40 MB of free hard disk space
The X-CUBE-NFC5 firmware and the related documentation are available at www.st.com.

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Board setup
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2 Board setup
To set up the board;
1
Connect the X-NUCLEO-NFC05A1 expansion board to the STM32 Nucleo board
from the top through the Arduino®UNO R3 connectors
2
Power the STM32 Nucleo board using a Mini-B USB cable
3
Program the firmware on the STM32 Nucleo board using the provided example
4
Reset the MCU using the reset button available on the STM32 Nucleo board.
The evaluation kit is ready to be used.

Hardware
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3 Hardware
The X-NUCLEO-NFC05A1 expansion board allows the user to test the functionality of the
ST25R3911B IC
a
, which supports the reader/writer mode
b
.
Program the microcontroller on the STM32 Nucleo board.
The ST25R3911B IC module and the STM32 Nucleo board are connected through CN5,
CN6, CN8 and CN9 connectors (see the tables below).
Table 1: Interconnections between the X-NUCLEO-NFC05A1 expansion board and the Nucleo-
L476RG board (left side)
Signal
Connector
Pin number
Nucleo-L476RG
X-NUCLEO-NFC05A1
NC
CN6
Power
1
-
-
IOREF
2
-
3V3 (VDD_IO)
RESET
3
-
-
3V3
4
-
3V3 (VDD_IO)
5V
5
-
5V (VDD)
GND
6
-
GND
GND
7
-
GND
VIN
8
-
-
A0
CN8
Analog
1
PA0
IRQ_MCU
A1
2
PA1
MCU_LED1
A2
3
PA4
MCU_LED2
A3
4
PB0
MCU_LED3
A4
5
PC1
-
A5
6
PC0
-
Table 2: Interconnections between the X-NUCLEO-NFC05A1 expansion board and the Nucleo-
L476RG board (right side)
Signal
Connector
Pin number
Nucleo-L476RG
X-NUCLEO-NFC05A1
D15
CN5
Digital
10
PB8
-
D14
9
PB9
-
AVDD
8
AVDD
-
GND
7
GND
GND
D13
6
PA5
CLK_MCU
a
For the chip complete feature list refer to the ST25R3911B datasheet.
b
For further details on the supported features, refer to this user manual introduction.

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Hardware
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Signal
Connector
Pin number
Nucleo-L476RG
X-NUCLEO-NFC05A1
D12
5
PA6
MISO_MCU
D11
4
PA7
MOSI_MCU
D10
3
PB6
/SS_MCU
D9
2
PC7
-
D8
1
PA9
-
D7
CN9
Digital
8
PA8
MCU_LED6
D6
7
PB10
-
D5
6
PB4
MCU_LED4
D4
5
PB5
MCU_LED5
D3
4
PB3
-
D2
3
PA10
-
D1
2
PA2
-
D0
1
PA3
-
3.1 Host interface and GPIO connection
The X-NUCLEO-NFC05A1 expansion board contains the ST25R3911B-AQFT chip and is
powered by the STM32 Nucleo board.
The ST25R3911B is driven by the microcontroller via SPI interface.
The six LEDs indicate the detected technology (for example ISO14443 Type A).

Hardware
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3.2 X-NUCLEO-NFC05A1 expansion board component
placement
Figure 2: X-NUCLEO-NFC05A1 component placement

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Component description
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4 Component description
4.1 ST25R3911B device
The ST25R3911B-AQFT is a highly integrated NFC initiator/HF reader IC embedding:
the analog front end (AFE) and a highly integrated data framing system for:
ISO 18092 (NFCIP-1) initiator
ISO 18092 (NFCIP-1) active target
ISO 14443A and B reader (including high bit rates)
FeliCa™ reader
The implementation of other standard and custom protocols (like MIFARE™ Classic) is
possible by using the AFE and implementing framing in the external microcontroller
(Stream and Transparent modes).
4.2 Schematic diagrams
4.2.1 USB connectivity and power supply
The X-NUCLEO-NFC05A1 expansion board can be connected via Arduino®UNO R3
connectors to the STM32 Nucleo board.
A green LED indicates if the 5 V supply is present on the X-NUCLEO-NFC05A1 expansion
board.
The six status LEDs are controlled via MCU.
Additional components are placed for the 5 V supply filtering.
Several solder jumpers enable an alternative connection of SCLK_MCU and /SS_MCU to
the STM32 MCU.

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Figure 3: STM32 Nucleo connector schematic diagram

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Component description
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4.2.2 ST25R3911B schematic diagram
The ST25R3911B is directly connected to the filtered 5 V USB supply. There are additional
supply filtering components placed close to the NFC/HF reader IC.
Jumper JP200 can be used to measure the chip supply current.
If this measurement is performed, the ferrite beat L301 has to be removed.
Capacitors 200 to 203 provide additional filtering of the ST25R3911B supply.
During layout all decoupling capacitors have been placed as close as possible to the
ST25R3911B chip. Special care has been taken for C209, C201, C213 and C200 since
these decoupling capacitors are used for the high power driver stage.
To demonstrate the capacitive wake-up feature, two capacitive electrodes are placed on
the PCB. Additional electrodes can be connected using the P200 and P201 UFL
connectors.
For SPI cross-connecting another reader PCB, the resistors R200 to R204 can be
removed.
J201 allows to bypass the internal VSP_RF regulator in case the output current is > 200
mA and needs to be supported.

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Figure 4: ST25R3911B schematic diagram

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Component description
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4.2.3 Antenna and matching network components
This schematic diagram contains the matching network and the automatic antenna tuning
capacitors as well as the alternative NFC Forum matching components.
In the default configuration, the X-NUCLEO-NFC05A1 expansion board is populated with a
VHBR tuning, which allows communication to speed up to 3.4 Mbps.
The Q-factor is doubled and bitrates up to 848kbps are supported, by switching the
components listed in the following table.
Table 3: Matching variant
VHBR Matching
NFC Forum Matching
C302
C302_NFCF
C309
C309_NFCF
R300
R300_NFCF
R301
R301_NFCF
To support VHBR bit rates, the antenna is matched to a system Q-Factor of 8.
By switching to the NFC Forum matching components, the system Q-Factor is increased to
16. This can increase read range by up to 20% depending on the communication
technology, but limits the maximum supported bit rate to 848kbps.
a
.
The etched PCB antenna can be easily removed from the expansion board to connect a
custom antenna using the connector J300.
The matching topology supports the connection of one custom differential antenna or two
single-ended antennas. The two single-ended antennas can then be multiplexed in
software using the single and rfo2 bits of IO Configuration Register 1.
a
Further information about antenna matching can be found at www.st.com/st25r

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Figure 5: Matching circuit schematic diagram

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4.3 PCB Layout
4.3.1 PCB layers
As the ST25R3911B is a high power RF transmitter, the NFC reader layout must be done
carefully.
The decoupling capacitors are located as close as possible to the positive and negative
power supply pins (for example VSP_RF and VSN_RF).
Since the chip is using a differential output driver stage, the antenna matching network is
treated as a differential network.
The space between the components is kept as small as possible and the whole network is
routed completely symmetrical.
Via stitching and via shielding is used to maintain a low impedance and prevent short
return current loops.
The RF traces are protected by via stitching in combination with guard rings to create a via
wall: this keeps the PCB electromagnetically 'quiet'.
A via shield is used to create a vertical copper barrier through the PCB, to help reduce
crosstalk and electromagnetic interference in a route carrying an RF signal.
The RFI traces and AAT lanes are routed as close as possible to each other.
4.3.2 Top layer
The top layer contains most of the components and PCB traces. The unused areas around
the IC are filled with GND planes guarded using via stitching.
The important analog traces are surrounded by GND vias.
Figure 6: PCB layout top layer

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4.3.3 Mid layer 1
The mid layer 1 is a pure GND plane. It provides a low ohmic DC path for the GND
connection.
Figure 7: PCB layout mid layer 1
4.3.4 Mid layer 2
Mid layer 2 is used for power distribution. It contains the power planes for the ST25R3911B
5 V supply and the 3.3 V to communicate with the STM32 Nucleo board.
Figure 8: PCB layout mid layer 2

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4.3.5 Bottom layer
The bottom layer is mainly GND plane. Some traces are routed through the bottom plane.
Figure 9: PCB layout bottom layer

Bill of materials
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5 Bill of materials
Table 4: X-NUCLEO-NFC05A1 bill of materials
Item
Q.ty
Ref.
Part/Value
Description
Manufacturer
Order code
1
0
C202
DNM
2
0
J300
DNM
3
0
J301
DNM
4
0
JP200
DNM
5
0
C303,
C306
DNM
6
0
J200,
J202
DNM
7
1
C100
0402, 0.01 µF,
25 V, ± 10%,
X7R
AVX
0402YC101KAT2A
8
5
C101,
C208,
C209,
C210,
C211
0402, 0.01 µF,
25 V, ± 10%,
X7R
AVX
04023C103KAT2A
9
0
P200,
P201
DNM
HRS
(HIROSE)
U.FL-R-SMT-1(10)
10
1
LED100
Green LED
Lite-On
LTST-C190KGKT
11
6
LED101,
LED102,
LED103,
LED104,
LED105,
LED106
Blue LED
Lite-On
LTST-C190TBKT
12
2
C201,
C203
0402, 0.1 µF,
10 V, ± 10%,
X5R,
MULTICOMP
MC0402X104K100CT
13
2
C301,
C310
0603, 10 pF,
50 V, 1%, C0G
/ NP0
MULTICOMP
MC0603N100F500CT
14
4
J100,
J101,
J302,
J303
MULTICOMP
MC00625W040210R
15
1
Y200
Crystal
MURATA
XRCGB27M120F3M00R0
16
2
C200,
C215
0402, 1 µF,
16 V, ± 10%,
X5R,
MURATA
GRM155R61C105KA12D
17
2
C206,
C207
0402, 8.2 pF,
50 V, ±
0.25 pF, C0G /
NP0
MURATA
GRM1555C1H8R2CA01D