| Summary: | 碩士 === 國立交通大學 === 電控工程研究所 === 107 === Personal health care is gaining popularity due to advances in wearable devices and IoT technology. Medical devices can detect personal physiological conditions at any time for long-term observation and analysis. To prevent the user from misaligning between the wearable device and the tested part during the activity, and cause physiological signals to have errors during reading. The biomedical sensor can be designed as an electronic skin patch that will be attached to the skin for accurate physiological signals. In addition, the electronic patch with flexibility and thinness also brings comfort and convenience to the user. Since the battery is bulky and cannot be fabricated on a flexible substrate, the power source of the electronic patch will be replaced by wireless power transfer. Magnetic resonance transmission power to the patch at 13.56 MHz in the ISM band. By transmitting power at high frequency resonance, in addition to increasing the transmission distance, the area of the resonant coil can be reduced to conform to the size of the patch. This thesis presents a single-stage regulating rectifier which is wireless power transfer receiver of the electronic patch. Active switching full-wave bridge rectifier reduces conduction loss and increases voltage conversion rate. Delay lock loop feedback controller improves the disadvantages of switching delay times at high frequencies that significantly affect power conversion efficiency. Not only the efficiency of wireless power receiver but also large chip area is limited by the two-stage design, which constitutes rectifier and voltage regulator. The voltage rectification and regulation are achieved simultaneously in a single-stage rectifier through 1X/0X mode control. The PFM control is utilized to select the switching frequency of the system in order to maximize the transient response during heavy-load and to minimize the switching power losses during light-load. All circuits are fabricated in TSMC 0.35 μm process. The whole chip area is 2.72 mm2. The output voltage is maintained at 3.3V at steady state to supply power to the biomedical sensor. The peak efficiency is about 86% with output power = 200mW.
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