應用於近場通訊技術之13.56MHz高效率無線傳輸電源管理系統

Abstract

近場無線通訊已成為近年手機不可或缺的一部份，為了讓近場通訊之系統能擁有更高的效率的電源供應，本論文提出了一可接受高輸入範圍之無線電力傳輸電源管理系統。傳統的整流器之輸出受限於輸入弦波之擺幅，本論文將自動切換電容倍率調整系統加入整流器用以增加最大輸入範圍的限制，並利用自我校正系統避免抽載影響切換之精確度。此論文之供電系統採用40奈米製程電路轉換交流電源至直流，並使用線性穩壓器提供穩定輸出電壓。此外，此論文之供電系統可藉由高速響應以及精準的切換達到最高85%的能源轉換效率。

Near field communication (NFC) becomes an essential part in the mobile devices in the near future. In order to provide NFC device high efficiency power source, A wide input AC range wireless power transfer (WPT) power management system is proposed. The minimum power received from the WPT is limited to the minimum allowable input AC source because conventional rectifier only regulates input AC to a desired DC voltage. Automatically adjusting ratio switched-capacitor (ADR-SC) technique is merged into the rectifier for high efficiency and extension of input AC range. Self-calibration of the output voltage is proposed to ensure accuracy even when the drop voltage occurs due to the load current across the SC. The test chip of the WPT system with the ADR-SC technique was fabricated in 40nm CMOS process. Experimental results show AC source from induction of magnetic field is rectified and converted to DC voltage for supplying the NFC controller through the low-dropout (LDO) regulator. Moreover, highest 85% total efficiency is achieved due to fast and accurate operation of the ADR-SC technique.