CSR:Small: Enabling Aggressive Voltage Scaling for Real-Time and Embedded Systems with Inexpensive yet Efficient Power Conversion

This project seeks to improve the energy efficiency of cost-sensitive embedded computer systems by splitting them into multiple separate voltage domains and running each as efficiently as possible by adjusting voltage and frequency dynamically. Improving energy efficiency allows a designer to extend a system?s operational life, reduce battery size and weight, and/or improve functionality. Switch-mode power supplies are commonly used to convert power efficiently from one voltage level to another. However, existing switching power supplies are often quite expensive compared with the microcontrollers and peripherals which they power. The major challenge in exploiting multiple voltage domains to save energy is to make power supplies that are efficient yet inexpensive enough to be practical for low-cost devices. The innovation here is to move control of the power supply into software and a low-cost generic microcontroller, which can be shared by the embedded application. Real-time systems scheduling techniques ensure that the entire system works reliably and that the power supply does not emit electromagnetic noise during periods that the system needs to perform noise-sensitive operations. Advanced Gallium Nitride (GaN) transistors are used to achieve high switching frequencies, enabling the use of smaller and less expensive components. New, highly efficient methods are developed to store and use energy from energy-scavenging devices (photovoltaic, thermoelectric, ambient radio).

Improvements in power supply technology mean lower energy consumption and longer battery life for electronic devices, and lower production costs. Beyond developing such technology, the project advances education in it.