用於生醫應用具高能量轉換效率主動式整流器之被動式近場通訊標籤

Design of a Passive Near Field Communication Tag with High Power Conversion Efficiency Active Rectifier for Biomedical Applications

呂季桓(Chi-Huan Lu)

指導教授 ： 林宗賢

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2016年)

https://doi.org/10.6342/NTU201610505

摘要

植入式醫療設備(IMDs)目前應用於疾病的監測與診斷，由於電池的尺寸與續航力的問題，無線能量傳輸（WPT）系統被廣泛作為植入式醫療設備的電源供應來源。為了能在不損害身體組織的條件下，提供足夠的功率以及穩定的電壓，如何提升無線能量傳輸系統的轉換效率是非常重要的議題。此外，傳統上使用生醫應用頻帶之無線收發機進行數據傳輸，但高功率消耗的收發機並不適合應用於植入式醫療設備。
本論文將描述一個低功率消耗，操作於13.56 MHz的被動式近場通訊標籤晶片。其中近場通訊天線可同時用於無線能量傳輸以及資料傳輸，不需要額外設計其他頻帶之無線收發機，可減少整體系統的功耗及面積。此外提出延遲補償技術，用於改善主動式整流器開關時機，以實現高能量轉換效率和電壓轉換比。此標籤晶片是使用台積電0.18微米製程設計。解調器和時脈產生器共消耗72.7微瓦。主動式整流器在500歐姆的負載下，能量轉換效率為80.2~85.7％，電壓轉換比82.1~86.8％，並且最大輸出功率為30.5毫瓦。

關鍵字

植入式醫療設備 ； 近場通訊 ； 無線能量傳輸 ； 主動式整流器

並列摘要

Wireless power transfer (WPT) system plays an important role for implantable medical devices (IMDs), which are used for disease monitoring, diagnosis and prosthesis. The size and power conversion efficiency are the critical issues of providing enough power and voltage supply without damaging body tissues. Conventionally, a MedRadio band transceiver was integrated into the system for data transmission. However, larger power consumptions and chip size are not suitable for IMDs applications.
In this work, a passive NFC tag with high PCE active rectifier is implemented. The inductor coil for NFC antenna is reused for wireless power transfer to reduce the system size. Both turn-on and turn-off delay compensation techniques are used to achieve high power conversion efficiency and voltage conversion ratio under large range of input amplitudes, PVT and process variations. The tag is fabricated in TSMC 0.18-μm CMOS technology. It consumes 72.7 μW with 1.8 V supply for 10% ASK demodulation and clock generation. The PCE is 80.2 ~ 85.7％ and VCR is 82.1 ~ 86.8% at 500 Ω load, and the maximum output power is 30.5 mW.

並列關鍵字

implantable medical devices ； Wireless power transfer ； Near field communication ； active rectifier

參考文獻

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