Ultra-low Power Multi-sensor Data Logger with NFC Interface
Created: Mar 03, 2016
No description available.
The cold chain monitoring is the process of ensuring a certain product temperature to remain constant upon shipping and distribution. The ultra-low power multi-sensor data logger with NFC interface reference design integrates multiple sensors for cold chain monitoring. The board features wireless communication through RF430CL330H dynamic near field communication (NFC) interface transponder. The TMP112 device is a digital temperature sensor ideal for NTC/PTC replacement and has an accuracy of ±0.5°C. The OPT3001 is an ambient light sensor that measures the intensity of visible light. For humidity measurement, the HDC1000 is a digital humidity sensor with integrated temperature sensor. The board also comes with MSP430 mixed-signal microcontroller.
In this reference design, the CR2032 coin cell (220mAh at 3V) powers the board. The RF430CL330H is a device that combines a contactless NFC/RFID interface and a wired I2C interface to connect the device to a host. It uses I2C communication to write/read NDEF communication and can also be updated through wireless communication using ISO/IEC 14443 Type B compliant RF interface that supports up to 848 kbps. The sensors are connected via I2C and each data coming from the sensors is log to the MSP430. The board does not include switches to be configured because an NFC enabled smartphone can be use to send configuration. This configuration includes Real-Time-Clock, both date and time, polling interval, and sensor mode. Sensor mode can be mode 0 which include temperature only, mode 1 - temperature and light, mode 2- temperature and humidity.
The power rail of this reference design is separated to ensure low power consumption. The MSP430 controls the power rail for the I2C compatible devices so that devices are only powered as needed during sensors measurement and RF configuration. When idle, the MSP430 enters low power mode and the supply to the sensors is cut-off, thus resulting to a consumption of current under 1uA. The reference design can be applicable to monitor food, medical, and pharmaceutical products.