Enhanced efficiency energy-scavenging interface, method for operating the energy-scavenging interface, and energy-scavenging system comprising the energy-scavenging interface

摘要

An energy-scavenging interface includes first and second switches connected in series between an input and reference, and third and fourth switches connected in series between the input and an output. A control circuit closes the first and second switches and opens the third switch for a first time interval to store charge in a storage element. A scaled copy of a peak value of the charging current is obtained. The control circuit then opens the first switch and closes the third and fourth switches to generate an output signal as long as the value in current of the output signal is higher than the value of said scaled copy of the peak value.

主权项

1. An energy-scavenging interface, comprising:
a first input terminal configured to receive an electrical input signal from a first terminal of a first storage element; a second input terminal coupled to a second input terminal of the first storage element; a first output terminal connected to a first terminal of a second storage element and configured to supply an output signal; a second output terminal connected to a second terminal of the second storage element; a first transistor switch and a second transistor switch having source-drain paths connected in series between the first input terminal and the second output terminal; a third transistor switch and a fourth transistor switch having source-drain paths connected in series between the first input terminal and the first output terminal; and a control circuit including a current mirror circuit connected to the second transistor switch, said control circuit configured to:
control the first and second transistor switches in a closed state and the third transistor switch in an open state for a first time interval having at least one first time duration during which the first storage element stores electric charge;generate using the current mirror circuit a first current signal that is a scaled copy of a peak value of the electric current in the first storage element during the first time interval;control the first transistor switch in an open state and the third and fourth transistor switches in a closed state to generate the output signal that supplies the second storage element; andmaintain the first transistor switch in the open state and the third and fourth transistor switches in the closed state as long as the current of the output signal is higher than the first current signal.