Circuit and Method to Improve Energy Harvesting Efficiency in Piezoelectric Harvesters

Applications

This technology has various energy harvesting applications such as battery life-time enhancer, pressure sensors, wireless sensor nodes, etc.

Problem Addressed

These designs address the currently low energy harvesting efficiency of piezoelectric harvesters.

Technology

This invention presents a circuit technology using a bias-flip rectifier technique which improves multi-fold, the power extraction capability as compared to conventional full-bridge rectifiers and voltage doublers. The bias-flip rectifier uses an inductor which can be shared with a multiplicity of DC-DC converters on the same energy processing circuit through an arbiter which controls access to the inductor. On-chip implementation of a gate-drive circuit can prevent the bias-flip switches from breaking down due to high voltage. The technology is not limited to piezoelectric harvesters and can be used in general with any input having similar electrical characteristics to a piezoelectric harvester.

Advantages

  • Improved efficiency in energy harvesting