Wireless Shelf Life Monitoring and Real Time Prediction in a Supply-Chain of Perishables Goods

This paper discusses the huge potential of a Wireless Sensor Network (WSN) as a tool for real-time monitoring in a perishable goods supply chain according to the pressing need of security and food certification. The combination of an appropriate monitoring system and further data processing create a tool that can provide the most useful information for each application. In this paper we propose a case study

A 1.6-V Tolerant Multiplexer Switch with 0.96-V Core Devices in 28-nm CMOS Technology

The reduction of the nominal supply voltage of CMOS technologies with scaling comes with the decrease of the maximum tolerable voltage of the devices. This poses challenges in implementing circuit blocks that are compliant with standardized communication protocols or deal with off-chip signals in voltage domains larger than the nominal supply (e.g., 1.8 V, 3.3 V, 5 V). Design techniques such as cascoding, voltage shifting and adaptive biasing are effective at removing the need for customized voltage resistant input/output (I/O) devices since they prevent intolerable voltage drops. However, at the input of multiple-channel blocks, the design of switches of multiplexers results critical as the input and the output nodes can assume values beyond the signal range, causing harmful biasing configurations. This paper presents the architecture of a switch for input channel multiplexers able to handle signals up to twice the nominal supply voltage of the employed devices. Its effectiveness has been proved by implementing a 1.6V switch with the core MOS transistors of the 28nm CMOS technology with 0.96V nominal supply voltage. The comparison with a benchmark switch based on 1.8V I/O devices showed that both a larger area (slightly more than twice) and static current consumption ( 40mu text{A} ) are required

Fluids energy harvesting system with low cut-in velocity piezoelectric MEMS

Energy harvesting from environmental vibrations has established as an effective and green solution for electric energy production. In particular, fluid flows like the wind represent a steady and ubiquitous energy source. Traditional fluids harvesters are based on huge and bulky infrastructures like turbines, with a high environmental impact and a quite high cut-in speed (higher than 3÷4 m/s) for the fluids to be harvested. Transducers based on piezo-electric devices in the micrometric scale have pushed this value down by about one order of magnitude. The development of nanostructured piezo-electric transducers in the submicrometric scale offers a new generation of devices capable of converting the energy of very slow fluids (velocities lower than 1 m/s), like human breath, thanks to their high flexibility. The electronic interface circuit demanded of harvesting the energy from such a transducer is called to sense output signals of hundreds of millivolts with power equal to few microwatts or less. Active architectures must be employed even though they suffer for a start-up phase and the power demand. For building up the circuit supply voltage in few hundreds of milliseconds with the mentioned input power, we propose the employment of two storage devices so that the powering of interface circuit is decoupled from the energy storing. For harvesting all the peaks of the input waveform down to 50 mV, a detector based on current sensing and offset rejection through AC coupling is proposed. © 2017 IEEE