Power management system IC for next-generation Internet-of-Things with an integrated microbattery

• Main Author: Dong, Zhaoyang
• Other Authors: Chang Joseph
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/158743
• Institution: Nanyang Technological University

To solve the power supply problem for Internet of Things devices, this report presents a power management circuit with integrated microbatteries, which can harvest vibration energy from piezoelectric transducer and deliver energy to the Bluetooth Low Energy load. The integrated batteries collect excess harvested energy and supply the load when the harvested energy is insufficient, which enables the designed circuit to have a longer lifetime than the pure battery solution and be more reliable than the pure energy harvesting circuit. The design process and operating principle of the overall circuit are discussed in detail in this report. On the basis of simulations, this circuit features a wide input voltage range of 3.95-22.1V (generated by the piezoelectric transducer), small load ripple and high output voltage stability. The overall circuit achieves a maximum power efficiency of more than 90.29%. A printed circuit board (PCB) is designed in this project with a size of 5.21cm×2.79cm×1.6mm, which is moderately compact for portable applications. In addition, this report provides a comprehensive literature review of the piezoelectric energy harvester and power management circuits based on it, which is essential for the further design of a fully integrated circuit.