Design of RF-DC Rectifier and Hysteresis-current-controlled Buck Converter

• Main Authors: LEI, CHIA-CHENG, 雷家正
• Other Authors: HWANG, YUH-SHYAN
• Format: Others
• Language: en_US
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/g9d7c2

博士 === 國立臺北科技大學 === 電子工程系 === 107 === Wireless telemetry technologies can be adapted in the systems that measure something in distant or unreachable places, such as implanted medical devices, wireless sensor nodes and ecosystem monitoring. There are a station and several nodes in the wireless telemetry system. Generally, only a small-capacity battery or super-capacitor to supply the power of sensor nodes. Therefore, periodic recharging through RF signal are necessary for the batteries and capacitors in sensor nodes. A RF-DC rectifier with high efficiency and low operating voltage is essential in node side. In addition, there are many functions must be executed in the station side, such as data processing and RF transmitting. A fast response and high efficiency power management block is required in the station side for stable operation. In the first part of this thesis, a new hysteresis-current-controlled buck converter with AC sensing techniques is presented. The inductor current ripple can be sensed by sensing the terminal voltages of inductor. Combined with the hysteresis-current-controlled technique, sub-us transient response and high efficiency are obtained. The proposed buck converter have been fabricated with TSMC 0.35um 2P4M 3.3V/5V process. Experiment result shows the 0.5us transient response is obtained when loading current step from 550mA to 150mA. The efficiency can be up to 90.7% In the second part of this thesis, a 13.56MHz low-voltage and low-control-loss RF-DC rectifier is presented. Reducing reverse loss technique is adapted to reduce the reverse leakage current loss. Simulation results show the reverse leakage current reduction are significant. Higher output voltage can be obtained by multi-stage stacking method. Boost-type RF front-end converter is also presented. The circuit have been implemented with TSMC 0.18um 1P6M process. Experimental result shows the maximum power conversion efficiency can be up to 68.6% and 67.9% for 1-stage and 3-stage RF-DC rectifier, respectively. The maximum efficiency of RF front-end converter is 41.3%.