基于MLX90129的13.56MHz RFID设计方案
MLX90129是Melexis公司的13.56MHz 传感器标签/数据采集IC,它把用于外部电阻传感器的精密数据采集和广泛外设组合在一起,存取和控制通过ISO15693 RFID前端或主/从SPI端口进行,除了13.56MHz调谐天线外不需要其它元件. MLX90129具有带存取保护的4kb EEPROM,以及单独使用的数据采集模式,主要用在冷链监视,财产管理和监视,建筑物自动化以及工业,医疗和住宅区控制与监视.本文介绍MLX90129主要特性,方框图,应用方框图,以及多种应用框图和MLX90129 评估板框图,电路图和材料清单(BOM).
MLX90129: 13.56MHZ SENSOR TAG / DATALOGGER IC
The MLX90129 combines a precise acquisiTIon chain for external resisTIve sensors, with a wide range of interface possibiliTIes. It can be accessed and controlled through its ISO15693 RFID front-end or via its SPI port.Without any other component than a 13,56MHz tuned antenna, it becomes a RFID thermometer.
For measuring others physical quanTIties, one or two resistive sensors can be connected to make batteryless sensing point. In this tag mode, the chip can supply a regulated voltage to the other components of the application.
Adding a battery will enable the use of the standalone data logging mode. The sensor output data is stored in the internal 3.5kbits user memory. One can extend the storage capacity by connecting an external E2PROM to the SPI port.
The SPI port can also connect the MLX90129 to a microcontroller which allows more specific applications, like adding actuating capability or RF transmission.
The MLX90129 has been optimized for low power, low voltage battery and battery-less applications.
MLX90129主要特性和优势:
Versatile A/D interface for resistive sensors
ISO-15693 13.56MHz transponder
Slave / Master SPI interface
4 k-bit EEPROM with access protection
Standalone data-logging mode
Ultra low power
Battery or battery-less applications
Low cost and compact design
MLX90129应用:
Cold chain monitoring
Asset management and monitoring (security and integrity)
Building automation
Industrial, medical and residential control and monitoring
图1.MLX90129方框图
图2.MLX90129应用方框图
图3.MLX90129 RFID多传感器标签框图
图4.MLX90129数据采集框图
图5.MLX90129基于MCU的应用框图
MLX90129 评估板
The EVB90129 is an assembled printed circuit board that simplifies evaluation of the MLX90129 sensor tag IC and to facilitate the development of wireless sensor applications based on the MLX90129.
The EVB90129 was developed to demonstrate a wide range of applications, from fully passive sensor tag operation to complex data logging. Each of its elements can be reconfigured by means of jumpers.
The board can be powered either by an external voltage supply, the on-board battery or the electromagnetic field from a RFID reader.In addition to the internal temperature sensor of the MLX90129, the EVB90129 embeds 3 external sensors, light, temperature and potentiometer to demonstrate the flexibility for measurement of a variety of physical quantities. The custom prototyping area allows users to integrate their own sensor or circuit into this evaluation board.
The EVB90129 is capable of storing 128 Kbytes of datas in the SPI EEPROM memory connected to the MLX90129. The EVB90129 can be accessed and controlled through a contactless (RFID) or a contact (SPI) interface. The RFID access to the MLX90129 and the related commands are compliant with the ISO15693 standard. The SPI and other digital inputs/outputs from the MLX90129 are connected to an 8-pin connector of the EVB90129. This allows easy connection to a microcontroller.
图6.MLX90129 评估板外形图
图7.MLX90129 评估板框图
图8.MLX90129 评估板电路图
MLX90129评估板材料清单(BOM):