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Week #6: Discussion results
NFC technology and its components
Group #33
Group member:
Tianhao Han
Ximeng Sun(Susie)
Xing Cao(Star)
Zhuoran Yang
NFC(Near field communication)
Definition:
Near field communication, abbreviated NFC,
is a form of contactless communication
between devices like smartphones or tablets.
The Near Field Communication (NFC) Forum is a
non-profit industry association that promotes the use of
NFC short-range wireless interaction in consumer
electronics, mobile devices and PCs.
What is NFC ?
NFC comes from RFID(Radio Frequency IDentification)
 NFC have three standard:
FeliCaTM(SONY) ISO14443A, B(Philips)
Type A, Type B, Type F
 NFC is a set of short-range wireless technologies
 Operates at 13.56MHz on ISO/IEC 18000-3 air
interface and at rates ranging from 106Kbit/s to
424Kbits/s
 Theoretical working distance with compact standard
antennas: up to 20 cm (practical working distance of
about 4 centimeters)

How does it work ?
Involves an initiator and a target
2. Initiator actively generates an RF field
that can power a passive target
 Passive communication mode
 Active communication mode
1.
Application:





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Access Control: Replacing traditional keys for either
physical access (hotel room) or control (starting a
car)
Ticketing: Replacing paper tickets for social events
and public transportation
Contactless Payments: Mobile payments debited from
financial or MNO linked accounts
Interactive World: Marketing and exchange of
information such as schedules, maps, business card
and coupon delivery using NFC Marketing tags
Media Sharing: Transfer images, videos, music between
mobile phones
Social media e.g. "Like" on Facebook, "Follow" on
Twitter via NFC smart stickers in retail stores
• Security
• Bit rate is low(only few information can be past in a
short time)
• Short distance
Benefits for NFC technology
(Comparing with blue tooth)
•
•
•
•
•
Smaller power consumption
Simply set up and set-up time is short
Security
Less cost($2-$3 VS $20)
Larger market
Key features and benefits for
NFC Controller

Highly integrated transmission modules
for contactless communication at
13.56MHz including a microcontroller.
Comparing
Features
TI: TRF7970A
NXP: PN532
Cost(break out board)
Less than $30(Free
sample)
$39.95
Total power dissipation
100mW, 200mW
500mW
Operating temperature
average range
-40 centidegree to +110
centidegree
-30 to +85
Low power modes
Hard-Power-Down
mode(Less than1µA)
• Hard-Power-Down
mode(1µA typical)
• Soft-Power-Down
mode(22µA typical)
Decoder & Encoder
Integrated encoders,
decoders
Integrated
demodulators, decoders
Overall
TRF7970A is cheaper and available.
 TRF7970A’s documentations including
datasheet are public/full and available
directly without any registration or NDA.
 Support Direct Mode 0 "Raw RF SubCarrierData Stream" to encode/decode
all 13.56MHz subcarrier data stream.
 PN532 has more specific features.

Applications
*Mobile Devices (Tablets, Handsets)
*Secure Pairing(Paired wireless networks)
---------
Bluetooth,WIF
*Public Transport or Event Ticketing
*Passport or payment (POS) Reader System
*Short-Range Wireless Communication Tasks (Firmware
Updates)
*Product Identification or Authentication
*Medical Equipment or Consumables
*Access Control, Digital Door Locks
*Sharing of Electronic Business Cards
Two Official Suggestion of TRF7970A

Using Parallel Microcontroller Interface

Using SPI With SS Mode
TRF7970A Reader System Using
Parallel Microcontroller Interface
Schematic for a parallel MCU interface
General Application Consideration

Due to the low clock frequency on the
data_clk (pin 26) line, the parallel
interface is the most robust way to
connect the TRF7970A with the MCU.
General Application Consideration
Schematic shows matching to a 50 Ω
port, which allows connecting to a
properly matched 50 Ω antenna circuit or
RF measurement equipment
For example: a spectrum analyzer or
power meter.

TRF7970A Reader System Using SPI
With SS Mode
Schematic for SPI with an SS mode MCU interface.
General Application Consideration
Systems using the Serial Port Interface (SPI).
Short SPI lines, proper isolation of radio
frequency lines, and a proper ground area are
essential to avoid interference.
 The recommended clock frequency on the
data_clk line is 2 MHz.

Structure

There are two parts in NFC technique.
a)NFC analog front-end (one case is NFC
Controller with antenna).
b)Security unit. Depending on the application
requirements, it can be SIM, SD, SAM or other
chips.
To fulfill NFC technique. Here is the graph:
The block diagram for TRF7970A
Terminal Functions
Question time.
Thank you for your listening!