High-efficiency energy harvesting interface and corresponding energy harvesting system

An electronic device, comprising:

• a transducer to convert energy from an environmental or mechanical energy source into a transduced signal;
• a harvesting interface to receive the transduced signal on an input terminal and to supply an electrical-energy harvesting signal on an output terminal;
• an energy storage element coupled to the output terminal of the harvesting interface to receive the electrical-energy harvesting signal;
• a voltage converter coupled to the output terminal to generate a regulated voltage, wherein the harvesting interface is configured to:
• control the voltage converter in a switching mode to thereby maintain the electrical-energy harvesting signal between an upper threshold voltage and a lower threshold voltages in a first operating condition;
• generate said upper and lower threshold voltages during a second operating condition;
• and
• cyclically execute said first operating condition following upon each new execution of said second operating condition;
• and
• an electrical load to receive the regulated voltage.

An electrical-energy harvesting method, comprising:

• by a transducer, converting energy from an environmental energy source into a transduced signal;
• by a harvesting interface:
• receiving the transduced signal on an input terminal;
• supplying an electrical-energy harvesting signal on an output terminal;
• sampling an open-circuit voltage value of the transduced signal;
• generating an optimized voltage value starting from the open-circuit voltage value;
• generating an upper threshold voltage based on the optimized voltage value;
• generating a lower threshold voltage based on the optimized voltage value;
• and
• controlling a voltage converter in a switching mode to maintain the electrical-energy harvesting signal between the upper and lower threshold voltages in a first operating condition;
• by an energy storage element coupled to the output terminal of the harvesting interface, receiving the electrical-energy harvesting signal and storing electrical energy;
• and
• by the voltage converter coupled to the output terminal, generating a regulated voltage.