Overview
The ST25R3911B-ASWB, produced by STMicroelectronics, is a highly integrated NFC Initiator / HF reader IC. It includes the analog front end (AFE) and a highly integrated data framing system, supporting various NFC and RFID protocols such as ISO 18092 (NFCIP-1), ISO 14443A and B, ISO 15693, and FeliCa™. This device is optimized for infrastructure applications requiring optimal RF performance, flexibility, and low power consumption. It features automatic antenna tuning (AAT) technology and two differential low impedance (1 Ohm) antenna drivers, making it unique in the domain of HF reader ICs.
Key Specifications
| Parameter | Value |
|---|---|
| Power Supply Range | 2.4 V to 5.5 V |
| Peripheral Interface IO Pins Power Supply Range | 1.65 V to 5.5 V |
| Operating Temperature Range | -40 °C to 125 °C |
| Package Type | QFN32, 5x5 mm with wetable flank or wafer delivery |
| Maximum Power Output | Up to 1.4 W in differential output |
| Communication Interface | 6 Mbit/s SPI with 96 bytes FIFO |
| Supported Protocols | ISO 18092 (NFCIP-1), ISO 14443A and B, ISO 15693, FeliCa™ |
| Antenna Drivers | Two differential low impedance (1 Ohm) antenna drivers |
Key Features
- Automatic antenna tuning (AAT) technology for optimized antenna performance
- Low power capacitive sensor for card presence detection without switching on the reader field
- Low power RC oscillator and wake-up timer for periodic card presence detection
- Support for VHBR (Very High Bit Rates) up to 6.8 Mbit/s
- AM and PM demodulator channels with automatic selection
- DPO (Dynamic Power Output) up to 1.4 W in differential output
- User selectable and automatic gain control
- Transparent and stream modes to implement MIFARE™ Classic or other custom protocols
- Possibility of driving two antennas in single-ended mode
- Oscillator input capable of operating with 13.56 MHz or 27.12 MHz crystal with fast start-up
Applications
- E-government
- Access control
- Payment systems, including EMVCo® 2.6b compliance
- NFC infrastructure
- Ticketing systems
Q & A
- What is the primary function of the ST25R3911B-ASWB?
The ST25R3911B-ASWB is a highly integrated NFC Initiator / HF reader IC, designed for various NFC and RFID applications.
- What protocols does the ST25R3911B-ASWB support?
The device supports ISO 18092 (NFCIP-1), ISO 14443A and B, ISO 15693, and FeliCa™ protocols.
- What is the power supply range for the ST25R3911B-ASWB?
The device operates from a power supply range of 2.4 V to 5.5 V, with peripheral interface IO pins supporting 1.65 V to 5.5 V.
- How does the ST25R3911B-ASWB detect card presence?
The device uses a low power capacitive sensor, phase measurement, or amplitude measurement to detect card presence without switching on the reader field.
- What is the maximum power output of the ST25R3911B-ASWB?
The maximum power output is up to 1.4 W in differential output.
- What communication interface does the ST25R3911B-ASWB use?
The device uses a 6 Mbit/s SPI interface with a 96-byte FIFO.
- What is the operating temperature range of the ST25R3911B-ASWB?
The operating temperature range is from -40 °C to 125 °C.
- What package types are available for the ST25R3911B-ASWB?
The device is available in QFN32, 5x5 mm packages with wetable flank or wafer delivery.
- Does the ST25R3911B-ASWB support high bit rates?
Yes, it supports Very High Bit Rates (VHBR) up to 6.8 Mbit/s.
- Can the ST25R3911B-ASWB drive two antennas?
Yes, it can drive two antennas in single-ended mode.
