Atmel 公司的ATA5575M1 是低频(100 kHz 到150 kHz ) RFID无接触读写IC,单线圈连接到IC用作电源和双向通信接口.天线和芯片一起组成收发器或标签.片内的128b用户EEPROM能从基站中读和写,上行数据传输采用负载调制,下行是100%幅度调制(OOK)脉冲间隔编码比特流.典型应用频率为125kHz.本文介绍ATA5575M1主要特性, 方框图和RFID系统框图.

    ATA5575M1: Read/Write LF RFID IDIC 100 kHz to 150 kHz The ATA5575 is a contactless read/write identification IC (IDIC?) for applications in the 100-kHz to 150-kHz frequency band. A single coil connected to the chip serves as the IC’s power supply and bi-directional communication interface. The antenna and chip together form a transponder or tag.

    The on-chip 128-bit user EEPROM (16 bytes with 8 bits each) can be read and written byte-wise from a base station (reader). Data is transmitted from the IDIC (uplink) using load modulation. This is achieved by damping the RF field with a resistive load between the two terminals Coil 1 and Coil 2. The IC receives and decodes serial base station commands (downlink), which are encoded as 100% amplitude modulated (OOK) pulse-interval-encoded bit streams.

    The ATA5575 is an EEPROM-based circuit. It is optimized for maximum read range. Programming is also possible, but the write range is limited.

    The chip has to be locked after loading the application-specific data into the device. Until the enable bits are set properly, the ATA5575M1 transmits all digits “0” in unique format. Typical applications run at 125 kHz.

    ATA5575M1主要特性:

    ? Contactless Power Supply

    ? Contactless Read/Write Data Transmission

    ? Radio Frequency (RF) from 100 kHz to 150 kHz

    ? 128-bit EEPROM User Memory: 16 Bytes (8 Bits Each)

    ? 8-bit Configuration Memory

    ? High Q-antenna Tolerance Due to Built-in Options

    ? Standard Unique Format (Manchester, RF/64)

    ? 40-bitData Memory

    ? 14-bit Parity Memory

    ? 9-bit Header Memory

    ? On-chip Trimmed Antenna Capacitor

    – 330 pF ±3%

    – 250 pF ±3%

    ? Mega Pads 200 μm x 400 μm

    ? Mega Pads 200 μm x 400 μm with 25 μm Gold Bumps for Direct Coil Bonding

    ? Other Options:

    Direct Access Mode

    OTP Functionality

    ATA5575M1应用:

    – Access Control

    图3.采用ATA5575M1标签的RFID系统框图(2)