Related Experiment Videos
A 66pW Discontinuous Switch-Capacitor Energy Harvester for Self-Sustaining Sensor Applications
Xiao Wu1, Yao Shi1, Supreet Jeloka1
1University of Michigan, Ann Arbor, MI.
Symposium on VLSI Circuits : [Proceedings]. Symposium on VLSI Circuits
|April 11, 2017
Summary
This study introduces a novel discontinuous harvesting method for switch capacitor DC-DC converters, achieving ultra-low power energy harvesting with over 40% efficiency and a 10x improvement in performance.
Area of Science:
- Electrical Engineering
- Power Electronics
- Energy Harvesting
Background:
- Ultra-low power energy harvesting is crucial for autonomous systems.
- Traditional DC-DC converters face efficiency challenges at picowatt (pW) power levels.
- Minimizing switching and leakage losses is key for efficient energy harvesting.
Purpose of the Study:
- To develop a discontinuous harvesting approach for switch capacitor DC-DC converters.
- To enable efficient energy harvesting at ultra-low power levels (pW range).
- To optimize the trade-off between converter losses and Maximum Power Point Tracking (MPPT) losses.
Main Methods:
- Implemented a discontinuous harvesting strategy with slow charge accumulation and burst-mode transfer.
- Utilized a 15pW mode controller, automatic conversion ratio modulator, and moving sum charge pump.
- Designed the harvester in 180nm CMOS technology.
Main Results:
- Achieved >40% end-to-end efficiency across an input power range of 113pW to 1.5μW.
- Demonstrated a minimum input power requirement of 66pW.
- Exhibited a >10x improvement compared to previous ultra-low power harvesters.
Conclusions:
- The discontinuous harvesting approach significantly enhances efficiency for ultra-low power applications.
- The developed harvester overcomes limitations of traditional converters at pW levels.
- This technology paves the way for more efficient and autonomous low-power devices.