Low-Density, Ultralow-Power and Smart Radio Frequency Telemetry Sensor.

摘要

Automated systems are required to better manage food sterility and identify time-temperature aseptic processing parameters to curb food safety issues. Sensor solutions can be used in conjunction with radio frequency identification (RFID) systems to meet these requirements. The integration of a temperature sensor (and other sensor types) with an RFID reader continues to be an actively researched area. The on-chip integration of sensors intended for food processing and other applications provide the opportunity for miniaturization, low-cost and ultralow power operation in extreme environmental conditions. Such sensors are also required to have a reasonable wireless range in battery-less designs and / or provide enough power when a battery is desired to be recharged wirelessly. Hence, features such as an efficient RF-to-DC power conversion at the front-end of the sensor, on-chip integration of as many of the sensor's subcomponents as possible, and a design for ultralow power operation are critical.;This dissertation focuses on the demonstration of 3D IC design methodologies of a new type of inexpensive, small density, and ultralow power wireless CMOS temperature sensor that gathers temperature history in extreme 27-140 degree Celsius temperature ranges (with the potential to multiplex additional sensors) inside a food processing system and transmits data wirelessly. The sensor and associated core circuitry has been implemented in Tezzaron's 0.13 mum 3D CMOS process. A significant portion of power is lost due to rectifier inefficiency during CMOS RF to DC conversions to charge the sensor's power storage medium wirelessly. An efficient CMOS RF-DC conversion is achieved using CMOS diode threshold compensation and conduction angle enhancements to demonstrate more than 10% CMOS power conversion efficiency improvement. The sensor is designed to use optimized communication protocols and analog and digital design blocks for minimum power. The onchip integration of components, reduction of the power supply voltage from the typical power required by the CMOS process, subthreshold CMOS design of subcomponents and selective activation of design blocks has enabled the core components to operate with less than 1 muA of current. The power optimization has enabled the sensor to run long enough to sample and store the required data powered from a very tiny rechargeable supercapacitors. The 5 mm x 2.5 mm x 2.4 mm sensor is implemented in 0.13 mum 3D CMOS process. 3DIC technology is used to add capacitor arrays to stabilize the power supply when RF-powered.