Junrui Liang

Kinetic Energy Harvesting (KEH) is an emerging solution that captures ambient vibration energy to power battery-free electronics, enabling maintenance-free and eco-friendly Internet of Things (IoT) applications. A critical component in KEH systems is the power conditioning circuit, which interfaces with the upstream electromechanical transducer and delivers regulated power to downstream embedded digital devices. This talk provides a comprehensive overview of the physical principles, historical developments, and the latest advancements in switched-mode power conditioning circuits for KEH devices, which encompass piezoelectric, electromagnetic, and triboelectric energy sources. The discussion will focus on electromechanical dynamic interactions, self-powered solutions, multiple synchronous switching techniques, and resonance tuning, all aimed at enhancing the understanding, implementation, and improvement of upstream power interconnections. Another special attention will be given to the energy buffer-release mechanism, which ensures a stable and reliable energy supply to downstream electronics. Beyond the technical details, the speaker will also explore the challenges and opportunities associated with the technological transfer of battery-free IoT solutions, highlighting the path toward scalable, real-world applications.

Biography:

Junrui Liang received his Ph.D. in Mechanical and Automation Engineering from the Chinese University of Hong Kong in 2010. He is now an Associate Professor at the School of Information Science and Technology at ShanghaiTech University, Shanghai, China. His research interests include battery-free ambient IoT, low-energy embedded system, power electronics, energy harvesting, and mechatronics. Dr. Liang has published 196 technical papers in leading academic journals and international conferences. He is listed among the top 2% of scientists in the world, according to Stanford University’s report since 2020.

He is an Associate Editor of Journal of Intelligent Material Systems and Structures and IEEE CASS Newsletter, Past Chair of the Energy Harvesting Technical Committee in the ASME Smart Materials, Adaptive Structures & Intelligent Systems Division, Chair-Elect of Power and Energy Circuits and Systems Technical Committee in IEEE Circuits and Systems Society (CASS). Dr. Liang is an ASME Fellow and IEEE CASS Distinguished Lecturer.

Yan Lu

With the surging demands for extremely high current at sub-1V supply voltage level in high performance computing and AI training centers, conventional planar power delivery architecture on the XPU cards suffers from high I2R loss in the “last-millimeter” power delivery. With 48V replacing 12V bus, efficient high-density power conversion becomes one of the main bottlenecks for system integration. There is a wide voltage gap between the power bus and the digital rails at the point-of-load (PoL), calling for novel power conversion topologies and system architectures. To bridge this gap, switched-capacitor-inductor (SCI) hybrid DC-DC converter has been one of the hottest topics in the power management IC area. Meanwhile, recent advanced 2.5D/3D packaging technologies enable more design flexibility and topology innovations for the PoL vertical power delivery, especially in chiplet systems. In this talk, we will analyze the difficulties and introduce a few hybrid SCI DC-DC design examples from our research group. Then, we will share several of our observations and design suggestions for future works.

Biography:

Yan Lu

Professor, Department of Electronic Engineering, Tsinghua University, Beijing, China

Yan Lu received the Ph.D. degree in electronic and computer engineering from The Hong Kong University of Science and Technology (HKUST), Hong Kong, China, in 2013. From 2014 to 2024, he was with the State Key Laboratory of Analog and Mixed-Signal VLSI, University of Macau, Macau, China. On July 1st, 2024, He joined the Department of Electronic Engineering, Tsinghua University, Beijing, China, as a Full Professor with the endowed Xing-Hua Chair Professorship. He has authored/coauthored 200+ peer-reviewed technical articles, including 60+ ISSCC&JSSC papers and three books. His research interests include high-density power converters, integrated voltage regulators, wireless power transfer and energy-harvesting circuits and systems.

Dr. Lu has served as an ITPC Member for ISSCC, as the Power Management Subcommittee Chair for CICC, an IEEE SSCS Distinguished Lecturer (2022–2023) and an IEEE CAS Society Distinguished Lecturer (2025–2026). He has served as a Guest Editor for IEEE JSSC, TCAS-I, and TCAS-II. He is a Senior Associate Editor for IEEE TCAS-II, an Associate Editor for the Journal of Semiconductors and the IEEE Journal of the Electron Devices Society. He was a recipient/corecipient of the IEEE Solid-State Circuits Society Pre-Doctoral Achievement Award (2013–2014), the IEEE CAS Society Outstanding Young Author Award in 2017, and the ISSCC 2017 Takuo Sugano Award for Outstanding Far-East Paper.