This project explores the design of a fully integrated, switched-capacitor DC-DC converter to convert small amounts of energy from photovoltaic or other low voltage energy sources. Clever bootstrapping techniques are used to ensure circuit startup without high-voltage or mechanical assists. Nanopower oscillator topologies are being investigated for minimum power and input voltage operation. Advanced timing schemes are used to minimize charge reversion loss and clock driver short circuit currents for increased efficiency. A boosted output voltage around 1.5V is targeted for compatibility with older CMOS technologies, offering a power advantage in heavily duty cycled applications where leakage is dominant. This work will enable the integration of CMOS circuitry and power supply on the same substrate for true single-chip, autonomous computing platforms.
Project end date: 02/02/15