基于PN512设计的13.56MHz无接触通信收发技术

PN512是NXP公司的高度集成的13.56MHz无接触通信收发器,支持四种不同的工作模式:读/写模式支持ISO/IEC14443A/MIFARE和FeliCa方案以及支持ISO/IEC14443B,卡运作模式支持14443A/MIFARE和FeliCa方案和支持NFCIP-1模式.本文介绍PN512主要特性, 方框图, ISO/IEC14443A/MIFARE和FeliCa读/写模式通信框图, 共同读/写选通与主控制器连接框图以及典型应用电路图.

The PN512 is a highly integrated transceiver IC for contactless communication at 13.56 MHz. This transceiver IC utilizes an outstanding modulation and demodulation concept completely integrated for different kinds of contactless communication methods and protocols at 13.56 MHz.

The PN512 transceiver ICs support 4 different operating modes

•Reader/Writer mode supporting ISO/IEC 14443A/MIFARE and FeliCa scheme

•Reader/Writer mode supporting ISO/IEC 14443B

•Card Operation mode supporting ISO/IEC 14443A/MIFARE and FeliCa scheme

•NFCIP-1 mode

Enabled in Reader/Writer mode for ISO/IEC 14443A/MIFARE, the PN512’s internal transmitter part is able to drive a reader/writer antenna designed to communicate with ISO/IEC 14443A/ MIFARE cards and transponders without additional active circuitry. The receiver part provides a robust and efficient implementation of a demodulation and decoding circuitry for signals from ISO/IEC 14443A/MIFARE compatible cards and transponders. The digital part handles the complete ISO/IEC 14443A framing and error detection (Parity & CRC).

The PN512 supports MIFARE 1 KB or MIFARE 4 KB emulation products. The PN512 supports contactless communication using MIFARE higher transfer speeds up to 424 kbit/s in both directions.

Enabled in Reader/Writer mode for FeliCa, the PN512 transceiver IC supports the FeliCa communication scheme. The receiver part provides a robust and efficient implementation of the demodulation and decoding circuitry for FeliCa coded signals. The digital part handles the FeliCa framing and error detection like CRC. The PN512 supports contactless communication using FeliCa Higher transfer speeds up to 424 kbit/s in both directions.

The PN512 supports all layers of the ISO/IEC 14443B reader/writer communication scheme, given correct implementation of additional components, like oscillator, power supply, coil etc. and provided that standardized protocols, e.g. like ISO/IEC 14443-4 and/or ISO/IEC 14443B anticollision are correctly implemented.

In Card Operation mode, the PN512 transceiver IC is able to answer to a reader/writer command either according to the FeliCa or ISO/IEC 14443A/MIFARE card interface scheme. The PN512 generates the digital load modulated signals and in addition with an external circuit the answer can be sent back to the reader/writer. A complete card functionality is only possible in combination with a secure IC using the S2C interface.

Additionally, the PN512 transceiver IC offers the possibility to communicate directly to an NFCIP-1 device in the NFCIP-1 mode. The NFCIP-1 mode offers different communication mode and transfer speeds up to 424 kbit/s according to the Ecma 340 and ISO/IEC 18092 NFCIP-1 Standard. The digital part handles the complete NFCIP-1 framing and error detection.

Various host controller interfaces are implemented:

•8-bit parallel interface1

•SPI interface

•serial UART (similar to RS232 with voltage levels according pad voltage supply)

•I2C interface.

图1.PN512方框图

图2.PN512 ISO/IEC14443A/MIFARE读/写模式通信框图

图3.PN512 FeliCa读/写模式通信框图

图4.PN512共同读/写选通与主控制器连接框图

图5.PN512典型应用电路图