Abstract: A DC-DC converter independently supplies electrical loads. For each load, an output load signal is compared to a reference to generate a result indicating a need to supply the respective electrical load. A first detection is made as to whether a first electrical load needs to be supplied and a second detection is made as to whether any remaining electrical loads need to be supplied. The first electrical load is supplied if the first detection is positive and the second detection is negative.

Abstract: An electrical-energy harvesting system envisages a transducer for converting energy from an environmental energy source into a transduced signal, an electrical energy harvesting interface for receiving the transduced signal and for supplying a harvesting signal, and an energy storage element coupled to the electrical energy harvesting interface for receiving the harvesting signal. The electrical-energy harvesting system also includes a voltage converter connected to the electrical energy harvesting interface for generating a regulated voltage. The harvesting interface samples an open-circuit voltage value of the transduced signal, generates an optimized voltage value starting from the open-circuit voltage value, and generates an upper threshold voltage and a lower threshold voltage on the basis of the optimized voltage value.

Abstract: A MEMS speaker device including a membrane that forms a first capacitor and a second capacitor, respectively, with a top plate and with a bottom plate. The device includes a driving circuit that operates, during a first operating period, to move the membrane into a first position, in which the membrane is close to the bottom plate, and during a second operating period, to move the membrane into a second position, in which the membrane is close to the top plate. The device includes a testing circuit having a measuring circuit, which generates a first signal, based on a capacitance of one of the first capacitor and the second capacitor and a second signal based on a capacitance of one of the first capacitor and the second capacitor; and a comparator, which compares the first and second signals with at least one first electrical reference quantity.

Abstract: A transducer converts energy coming from an energy source into an electrical signal for storage as electrical energy on a first storage element. A switch is selectively actuated to pass electrical energy from the first storage element to a second storage element. The selective actuation of the switch is driven by sensing electrical energy stored in the second storage element. The switch is closed when electrical energy in the second storage element is sensed to fall below a first threshold. The switch is opened when electrical energy in the second storage element is sensed to rise above a second threshold.

Abstract: An electrical-energy harvesting system envisages a transducer for converting energy from an environmental energy source into a transduced signal, an electrical energy harvesting interface for receiving the transduced signal and for supplying a harvesting signal, and an energy storage element coupled to the electrical energy harvesting interface for receiving the harvesting signal. The electrical-energy harvesting system also includes a voltage converter connected to the electrical energy harvesting interface for generating a regulated voltage. The harvesting interface samples an open-circuit voltage value of the transduced signal, generates an optimized voltage value starting from the open-circuit voltage value, and generates an upper threshold voltage and a lower threshold voltage on the basis of the optimized voltage value.

Abstract: A dual input single output (DISO) regulator, includes a comparator configured to receive a first and second power supply signal and to provide a first compared signal; a first switch configured to couple the first power supply source to an intermediate node, and a second switch configured to couple the second power supply source to the intermediate node; a control logic circuit, coupled to the first comparator, to the first switch, and to the second switch, and configured to receive the compared signal to control the first and the second switch in a first and second operating condition based on the compared signal. The intermediate node being biased by an intermediate power supply signal correlated to the first or second power supply signal. The DISO regulator includes a low-dropout regulator, configured to provide a regulated power supply signal based on the intermediate power supply signal.

Abstract: A biasing circuit for an acoustic transducer is provided with: a voltage-booster stage, which supplies, on a biasing terminal, a boosted voltage for biasing a first terminal of the acoustic transducer; and filtering elements, set between the biasing terminal and the acoustic transducer, for filtering disturbances on the boosted voltage. The biasing circuit is further provided with switches, which can be actuated so as to connect the first terminal to the biasing terminal of the voltage-booster stage, directly during a start-up step of the biasing circuit, and through the filtering elements at the end of the start-up step.

Abstract: An energy harvesting circuit receives an input voltage from a transducer and uses a single inductor operating in a DC-DC converter charging mode to generate charging current at a first output coupled to an energy storage device where a supply voltage is stored. The energy harvesting circuit further receives the supply voltage from the energy storage device and uses the same single inductor operating in a DC-DC converter regulating mode to generate load current at a second output where a regulated load voltage is provided. The energy harvesting circuit switches between the charging mode and the regulating mode in accordance with a discontinuous mode (DCM) control process.

Abstract: An electrical-energy harvesting system envisages a transducer for converting energy from an environmental energy source into a transduced signal, an electrical energy harvesting interface for receiving the transduced signal and for supplying a harvesting signal, and an energy storage element coupled to the electrical energy harvesting interface for receiving the harvesting signal. The electrical-energy harvesting system also includes a voltage converter connected to the electrical energy harvesting interface for generating a regulated voltage. The harvesting interface samples an open-circuit voltage value of the transduced signal, generates an optimized voltage value starting from the open-circuit voltage value, and generates an upper threshold voltage and a lower threshold voltage on the basis of the optimized voltage value.

Abstract: An energy-scavenging interface receives an input signal from a transducer and supplies an output signal to a load. A switch is connected between the transducer and a reference node, and a diode is connected between the transducer and the load. A control circuit closes the switch for a time interval to permit energy storage in the transducer. A scale copy of a peak value of stored electric current is obtained. The switch is opened when the time interval elapses and the stored energy exceeds a threshold. The stored energy is then released to supply the load through the diode. The switch remains open as long as the value of current in the output signal exceeds the value of the scaled copy of the peak value.

Abstract: A system for driving a MEMS array having a number of MEMS structures, each defining at least one row terminal and one column terminal, envisages: a number of row driving stages, each for supplying row-biasing signals to the row terminal of each MEMS structure associated to a respective row; a number of column driving stages, each for supplying column-biasing signals to the column terminal of each MEMS structure associated to a respective column; and a control unit, for supplying row-address signals to the row driving stages for generation of the row-biasing signals and for supplying column-address signals to the column driving stages for generation of the column-biasing signals. The control unit further supplies row-deactivation and/or column-deactivation signals to one or more of the row and column driving stages, for causing deactivation of one or more rows and/or columns of the MEMS array.

Abstract: A modulated digital input signal is passed through a conditioning circuit to generate a first input signal. An error amplifier circuit receives the first input signal and a second input signal, and controls the operation of a MOS transistor to generate an output signal that is current modulated. The output signal is sensed to generate a feedback signal. A switching circuit selectively applies the feedback signal as the second input signal in response to a transition of the modulated digital input signal from a first logic state to a second logic state. The switching circuit alternatively selectively applies a fixed reference signal as the second input signal to the error amplifier in response to a transition of the modulated digital input signal from the second logic state to the first logic state.

Abstract: A rectifier circuit includes a first, second, third and fourth parasitic diodes electrically connected to form a full-wave diode-bridge rectifier. A first switch and a second switch are connected in parallel, respectively, to the first and second parasitic diodes, and a third switch and a fourth switch connected in parallel, respectively, to the third and fourth parasitic diodes. A first biasing network is configured to drive in conduction the first and second switches, during turning-on of the rectifier circuit, using a first turning-on signal that is a function of the input signal. A second biasing network is configured to close the third and fourth switches, during turning-on of the rectifier circuit, using a second turning-on signal that is a function of the input signal.

Abstract: A step-detection device for detecting the steps taken by a user (for counting) includes a transducer that generates an electrical transduction signal as a function of step mechanical activity. An energy scavenging system, coupled to the transducer, generates electrical energy starting from the mechanical activity in order to supply an output supply signal in response to the electrical transduction signal. A voltage-regulator generates a regulated supply signal from the output supply signal. A transmission stage, supplied by the voltage-regulating stage, initiates a wireless transmission indicative of step detection, that wireless transmission causing an increment of a step count at a remote location. The transmission stage makes the wireless transmission when the regulated supply signal exceeds a first threshold. Completion of the wireless transmission is indicative of the occurrence of a step.

Abstract: An energy harvesting interface receives an electrical signal from an inductive transducer and supplies a supply signal. The interface includes an input branch with a first switch and a second switch connected together in series between a first input terminal and an output terminal. The interface further includes a third switch and a fourth switch connected together in series between a second input terminal and the output terminal. A first electrical-signal-detecting device, coupled across the second switch, detects a first threshold value of an electric storage current in the inductor of the transducer. A second electrical-signal-detecting device, coupled across the fourth switch, detects whether the electric supply current that flows through the fourth switch reaches a second threshold value lower than the first threshold value. The second threshold is derived from the electric storage current.

Abstract: A converter includes an inductor configured to receive an input signal and output configured to supply an electrical load with an output signal. The converter operates to charge the inductor until a maximum pre-set current value is reached during a first operating condition in which the electrical load is not supplied. Next, the converter actively supplies the electrical load by partially discharging the inductor during a first time interval of a second operating condition. Then, the converter passively supplies the electrical load by the residual charge of the inductor during a second time interval, subsequent to the first time interval, of the second operating condition, by discharging the inductor completely.

Abstract: An energy scavenging interface has an input port receiving an electrical signal from a storage element of a transducer, and an output port supplying an output signal to an electrical load. The interface includes a first switch receiving the input signal; a second switch that supplying the output signal; and control logic configured to close the first switch and open the second switch for a first time interval having at least a first temporal duration and until current through the first switch reaches a threshold. A scaled copy of a peak value of current through the first switch is obtained during the first time interval. The control logic is further operable to open the first switch and close the second switch to supply current to the electrical load as long as the current of the output signal remains greater than the value of said scaled copy of the peak value.

Abstract: A DC-DC converter independently supplies electrical loads. For each load, an output load signal is compared to a reference to generate a result indicating a need to supply the respective electrical load. A first detection is made as to whether a first electrical load needs to be supplied and a second detection is made as to whether any remaining electrical loads need to be supplied. The first electrical load is supplied if the first detection is positive and the second detection is negative.

Abstract: A dual input single output (DISO) regulator, includes a comparator configured to receive a first and second power supply signal and to provide a first compared signal; a first switch configured to couple the first power supply source to an intermediate node, and a second switch configured to couple the second power supply source to the intermediate node; a control logic circuit, coupled to the first comparator, to the first switch, and to the second switch, and configured to receive the compared signal to control the first and the second switch in a first and second operating condition based on the compared signal. The intermediate node being biased by an intermediate power supply signal correlated to the first or second power supply signal. The DISO regulator includes a low-dropout regulator, configured to provide a regulated power supply signal based on the intermediate power supply signal.

Abstract: A MEMS speaker device including a membrane that forms a first capacitor and a second capacitor, respectively, with a top plate and with a bottom plate. The device includes a driving circuit that operates, during a first operating period, to move the membrane into a first position, in which the membrane is close to the bottom plate, and during a second operating period, to move the membrane into a second position, in which the membrane is close to the top plate. The device includes a testing circuit having a measuring circuit, which generates a first signal, based on a capacitance of one of the first capacitor and the second capacitor and a second signal based on a capacitance of one of the first capacitor and the second capacitor; and a comparator, which compares the first and second signals with at least one first electrical reference quantity.