Features

• AEC-Q100 qualified

• Operating modes

– Reader/writer

– Card emulation

– Active and passive peer to peer

• RF communication

– EMVCo 3.0 analog and digital compliant

– NFC-A / ISO14443A up to 848 kbit/s

– NFC-B / ISO14443B up to 848 kbit/s

– NFC-F / FeliCa™ up to 424 kbit/s

– NFC-V / ISO15693 up to 53 kb/s

– NFC-A / ISO14443A and NFC-F / FeliCa™

card emulation

– Active and passive peer to peer initiator

and target modes, up to 424 kbit/s

– Low level modes to implement MIFARE

Classic® compliant or other custom

protocols

• Key features

– Dynamic power output (DPO) controls the

field strength to stay within given limits

– Active wave shaping (AWS) reduces overand

under-shoots

– Noise suppression receiver (NSR) allows

reception in noisy environment

– Automatic antenna tuning (AAT) via

variable capacitor

– Integrated EMVCo 3.0 compliant EMD

handling

– Automatic gain control and squelch feature

to maximize SNR

– Low power capacitive and inductive card

detection

– Low power NFC active and passive target

modes

– Adjustable ASK modulation depth, from 5

to 40

– Integrated regulators to boost system

PSRR

– AM/PM and I/Q demodulator with

baseband channel summation or automatic

channel selection

– Possibility to drive two independent single

ended antennas

– Measurement of antenna voltage amplitude

and phase, RSSI, on-chip supply and

regulated voltages

External communication interfaces

– 512-byte FIFO

– Serial peripheral interface (SPI) up to

5 Mbit/s

– I2C with up to 400 kbit/s in Fast-mode,

1 Mbit/s in Fast-mode Plus, and 3.4 Mbit/s

in High-speed mode

Electrical characteristics

– Wide supply voltage and ambient

temperature range (2.6 to 5.5 V from -40 °C

to +105 °C, 2.4 to 5.5 V from -20 °C to

+105 °C)

– Wide peripheral communication supply

range, from 1.65 to 5.5 V

– Quartz oscillator capable of operating with

27.12 MHz crystal with fast start-up

Applications

The ST25R3920 device is suitable for a wide range of NFC and HF RFID applications,

among them

CCC digital key NFC reader in locations like door handles, B-Pillars or center consoles

NFC Forum compliant universal device for pairing applications

Qi charging protection and NFC-based charging for in-car chargers

EMVCo 3.0 compliant contactless payment terminal

Original equipment, consumable and short range location detection inside a car

ISO14443 and ISO15693 compliant general purpose NFC device

FeliCa™ reader/writer

Support of all five NFC Forum tag types in reader mode

Support of all common proprietary protocols, such as Kovio, CTS, B’.

Description

The ST25R3920 is an automotive grade high performance NFC universal device supporting

NFC initiator, NFC target, NFC reader, and NFC card emulation modes.

Designed for CCC (car connectivity consortium) digital key applications, the ST25R3920

enables fast product development for car access/start applications in areas like door handle

or center console, and enables additional functionality, like pairing or NFC card protection

combined with a Qi charger. Being very robust and noise tolerant while at the same time

reducing electromagnetic emission, the device works even under harsh conditions, enabling

an easier certification.

The device includes an advanced analog front end (AFE) and a highly integrated data

framing system for ISO18092 passive and active initiator, ISO 18092 passive and active

target, NFC-A/B (ISO14443A/B) reader including higher bit rates, NFC-F (FeliCa™) reader,

NFC-V (ISO15693) reader up to 53 kbps, and NFC-A / NFC-F card emulation.

Special stream and transparent modes of the AFE and framing system can be used to

implement other custom protocols in reader or card emulation modes.

The ST25R3920 features high RF power with dynamic power output to directly drive

antennas at high efficiency, achieving large interaction distance even with small antenna

sizes common in door handles. The device include additional features, making it

incomparable for low power applications. It offers low power card detection by performing a

measurement of the amplitude or phase of the antenna signal while reducing power

consumption to a minimum. Additionally, it contains a low power capacitive sensor to detect

the presence of a card without switching on the reader field.

The ST25R3920 is designed to operate from a wide power supply range (2.6 to 5.5 V from

-40 °C to +105 °C, 2.4 to 5.5 V from -20 °C to +105 °C), and a wide peripheral IO voltage

range (from 1.65 to 5.5 V).

Due to this combination of high RF output power, low power modes, wide supply rangeand

AEC-Q100 grade 2 qualification, the device is perfectly suited for automotive applications.