Abstract: A galvanically isolated current sensor for power converters is disclosed. The sensor includes a package housing a first integrated circuit (IC), a light emitting layer, an optical waveguide, a photosensing layer, and a second IC. The light emitting layer emits light proportional to a reference current. The optical waveguide modulates the light based on a magnetic field generated by the current to be sensed. The photosensing layer generates a photocurrent representative of the modulated light's intensity. The second IC outputs a sense current based on the photocurrent. The optical waveguide includes polarizers and a Faraday rotator material to effectuate the modulation. Different embodiments of control circuitry for processing the sense current are described, including a flash ADC-based system, a voltage-controlled oscillator with a high-speed counter, and a current-controlled delay line with a low-speed counter.

Abstract: Apparatuses, systems, and methods for a time domain voltage reference with zero quiescent current consumption are provided. An exemplary method includes outputting a first delay signal having a first delay that is based on an input voltage; outputting a second delay signal having a second delay that is based on a first voltage difference between the input voltage and an analog reference voltage; outputting first command signals that are based on a first time difference between the first delay and the second delay, wherein the first time difference corresponds to the first voltage difference; outputting a first counter signal indicative of a first value of a count of the counter, wherein the first value is based on the first command signals; and storing the first value, wherein a first programmable voltage delay line is configured to use the first value as a digital reference corresponding to the analog reference voltage.

Abstract: An irrigation system includes a fluid-inlet, a first fluid-path coupled to the fluid-inlet and having a first valve for controlling fluid-flow, and a second fluid-path coupled to the fluid-inlet and having a second valve for controlling fluid-flow. Fluid flow through a power harvester coupled to the second fluid-path causes generation of electricity. An energy storage device stores the generated electricity. A sensor measures the energy stored in the energy storage device. A controller is coupled to the sensor, the first valve, and the second valve. The controller determines if the stored energy is below a threshold, to open the second valve to allow fluid-flow through the second fluid-path and activate the power harvester when the stored energy is below the threshold, to close the second valve when the stored energy reaches or exceeds the threshold, and to control the first valve independently of the electricity generation to regulate irrigation.

Abstract: A galvanically isolated current sensor for power converters is disclosed. The sensor includes a package housing a first integrated circuit (IC), a light emitting layer, an optical waveguide, a photosensing layer, and a second IC. The light emitting layer emits light proportional to a reference current. The optical waveguide modulates the light based on a magnetic field generated by the current to be sensed. The photosensing layer generates a photocurrent representative of the modulated light's intensity. The second IC outputs a sense current based on the photocurrent. The optical waveguide includes polarizers and a Faraday rotator material to effectuate the modulation. Different embodiments of control circuitry for processing the sense current are described, including a flash ADC-based system, a voltage-controlled oscillator with a high-speed counter, and a current-controlled delay line with a low-speed counter.

Abstract: The present disclosure relates to a method for sanitization of a surface by emission of a plurality of sanitization wavelengths, and to a device for implementing the method. The method comprises emitting light using first LEDs configured to emit the sanitization wavelengths, receiving, by a circuit, a feedback signal from a light sensor indicating a light intensity received by the light sensor during the light emission, and controlling the first LEDs with the circuit based on the feedback signal.

Abstract: An irrigation system includes a first valve fluidly-coupled between an inlet pipe and an outlet pipe, and a second valve fluidly-coupled between the inlet pipe and a power harvester. The power harvester generates electrical power at a power output in response to fluid flowing therethrough. An energy storage unit is coupled to the power output to store generated voltage. Comparison circuitry compares the generated voltage to a threshold. Control circuitry causes the second valve to permit fluid to flow therethrough when the generated voltage is less than the threshold, causing generation of the electrical power by the power harvester when the generated voltage is less than the threshold. The comparison circuitry causes the second valve to prevent fluid flow when the generated voltage is at least equal to threshold, ceasing generation of the electrical power by the power harvester when the generated voltage is at least equal to the threshold.

Abstract: An example apparatus, computer-implemented method, and computer program product for determining a variable resistance of a conductive portion of a resistance-based sensing device are provided. An example apparatus includes a resistance-based sensing device having a conductive portion configured to indicate a physical characteristic of an environment based on a variable resistance of the conductive portion. The apparatus further includes a controller electrically coupled to the resistance-based sensing device, having a process and a storage device storing instructions that are operable, when executed by the processor, to cause the processor to transmit stored energy from an energy storage device to the conductive portion of the resistance-based sensing device, determine a time interval associated with a voltage drop in the energy storage device, and determine the variable resistance of the conductive portion of the resistance-based sensing device based at least in part on the time interval.

Abstract: A system to sanitize a surface includes an emitter. The emitter of the system to sanitize the surface includes: a light source configured to generate light at a sanitizing wavelength; a receiver configured to receive a wireless signal; and a processing circuit for the emitter configured to turn the light source on, turn the light source off, and adjust an intensity of light generated by the light source depending on the wireless signal. The system to sanitize the surface further includes a sensor. The sensor of the system to sanitize the surface includes: a photoelectric transducer configured to convert light at the sanitizing wavelength to a current; and a processing circuit for the sensor powered by the current and in communication with a transmitter to transmit the wireless signal, the processing circuit for the sensor being configured to control emission of the wireless signal depending on a power level supplied by the current.

Abstract: A wireless device includes an energy harvester and an energy storage that operate in a sequence of energy harvesting cycles to alternately harvest energy and release energy for supplying the wireless device. The wireless device also includes a processing circuit and a wireless communication circuit. A configuration method for the wireless device includes first step where a base station receives a signal from the wireless device indicating wireless communication circuit entry into a receiving operation mode. In a second step, the base station transmits configuration data to the wireless device. The received configuration data is temporarily stored in a memory area of the wireless communication circuit. In a third step, the temporarily stored configuration data is transmitted from the wireless communication circuit to the processing circuit for storage in a memory area. The second and third steps are carried out during distinct energy harvesting cycles of the wireless device.

Abstract: A system to sanitize a surface includes an emitter. The emitter of the system to sanitize the surface includes: a light source configured to generate light at a sanitizing wavelength; a receiver configured to receive a wireless signal; and a processing circuit for the emitter configured to turn the light source on, turn the light source off, and adjust an intensity of light generated by the light source depending on the wireless signal. The system to sanitize the surface further includes a sensor. The sensor of the system to sanitize the surface includes: a photoelectric transducer configured to convert light at the sanitizing wavelength to a current; and a processing circuit for the sensor powered by the current and in communication with a transmitter to transmit the wireless signal, the processing circuit for the sensor being configured to control emission of the wireless signal depending on a power level supplied by the current.

Abstract: Disclosed is an energy autonomous system including an energy transducer, a first capacitor, a second capacitor having greater capacitance than the first capacitor, and a microprocessor. The microprocessor includes a first terminal electrically coupled to the energy transducer and the first capacitor; a second terminal electrically coupled to the second capacitor; a switch that is in a conductive state in which the switch electrically couples the first terminal and second terminals together, or a nonconductive state in which the switch does not electrically couple first terminal and second terminals together; a voltage detector that detects a voltage at the first terminal; and a processor coupled to the voltage detector and the switch. The processor controls charging of the second capacitor by controlling the switch to be in the conductive state or the nonconductive state based on the voltage at the first terminal detected by the voltage detector.

Abstract: A first RF-to-DC circuit receives a radiofrequency signal and produces a first converted signal delivered to an energy storage circuit. A second RF-to-DC circuit, which is a down-scaled replica of the first RF-to-DC circuit, produces a second converted signal from the radiofrequency signal that is indicative of an open-circuit voltage of the first RF-to-DC circuit. The first RF-to-DC section includes N sub-stages, with a sub-set of sub-stages being selectively activatable. A window comparison of the second converted signal generates a first signal and a second signal indicative of whether the second converted signal is within a range of values proportional to a voltage reference signal. The sub-set of sub-stages is selectively deactivated, respectively activated, when the performed window comparison has a first result, respectively, a second result.

Abstract: An irrigation system includes a first valve fluidly-coupled between an inlet pipe and an outlet pipe, and a second valve fluidly-coupled between the inlet pipe and a power harvester. The power harvester generates electrical power at a power output in response to fluid flowing therethrough. An energy storage unit is coupled to the power output to store generated voltage. Comparison circuitry compares the generated voltage to a threshold. Control circuitry causes the second valve to permit fluid to flow therethrough when the generated voltage is less than the threshold, causing generation of the electrical power by the power harvester when the generated voltage is less than the threshold. The comparison circuitry causes the second valve to prevent fluid flow when the generated voltage is at least equal to threshold, ceasing generation of the electrical power by the power harvester when the generated voltage is at least equal to the threshold.

Abstract: An energy harvester includes an elongated tubular casing extending around a longitudinal axis between opposed first and second ends. A body is arranged in the casing. A helical electrical winding is wound around the longitudinal axis. The body is arranged to move along the longitudinal axis with alternate motion away from the first end towards the second end and away from the second end towards the first end. As a result of this alternate motion, an electromotive force is produced in the at least one helical electrical winding. Furthermore, at least one of the first and second ends includes a piezoelectric transducer that is configured to co-operate in a kinetic energy transfer relationship with the at least one body to generate an electric voltage as a result of the at least one body reaching, in the alternate motion, an end-of-travel position towards the piezoelectric transducer.

Abstract: A wireless device includes an energy harvester and an energy storage that operate in a sequence of energy harvesting cycles to alternately harvest energy and release energy for supplying the wireless device. The wireless device also includes a processing circuit and a wireless communication circuit. A configuration method for the wireless device includes first step where a base station receives a signal from the wireless device indicating wireless communication circuit entry into a receiving operation mode. In a second step, the base station transmits configuration data to the wireless device. The received configuration data is temporarily stored in a memory area of the wireless communication circuit. In a third step, the temporarily stored configuration data is transmitted from the wireless communication circuit to the processing circuit for storage in a memory area. The second and third steps are carried out during distinct energy harvesting cycles of the wireless device.

Abstract: The present disclosure relates to a method for sanitization of a surface by emission of a plurality of sanitization wavelengths, and to a device for implementing the method. The method comprises emitting light using first LEDs configured to emit the sanitization wavelengths, receiving, by a circuit, a feedback signal from a light sensor indicating a light intensity received by the light sensor during the light emission, and controlling the first LEDs with the circuit based on the feedback signal.

Abstract: A system to sanitize a surface includes an emitter. The emitter of the system to sanitize the surface includes: a light source configured to generate light at a sanitizing wavelength; a receiver configured to receive a wireless signal; and a processing circuit for the emitter configured to turn the light source on, turn the light source off, and adjust an intensity of light generated by the light source depending on the wireless signal. The system to sanitize the surface further includes a sensor. The sensor of the system to sanitize the surface includes: a photoelectric transducer configured to convert light at the sanitizing wavelength to a current; and a processing circuit for the sensor powered by the current and in communication with a transmitter to transmit the wireless signal, the processing circuit for the sensor being configured to control emission of the wireless signal depending on a power level supplied by the current.

Abstract: An energy-harvesting generator provides energy for storage in a capacitor. A sensing circuit senses a voltage across the capacitor and generates an activation signal as a function of the sensed voltage. The activation signal switches from a first value to a second value when the sensed voltage reaches an upper threshold and switches from the second value to the first value when the sensed voltage reaches a lower threshold. A signal transmitter powered by stored energy in the capacitor responds to the activation signal being switched to the second value by activating and transmitting a transmission signal. The signal transmitter further responds to the activation signal being switched to the first value by discontinuing transmission of the transmission signal and deactivating. A duration of time elapsing between de-activation and activation of the transmitter is indicative of an amount of energy harvested by the energy-harvesting electric generator.

Abstract: A first generator produces a first signal that is supplied to an energy storage circuit. Energy transfer circuitry coupled to the energy storage circuit transfers energy stored in the energy storage circuit to an output node. A driver circuit coupled to the energy transfer circuitry switches the energy transfer circuitry between a state where energy from the first signal is stored in the energy storage circuit and a state where energy stored in the energy storage circuit section is delivered to the output node. A voltage at the energy storage circuit varies between an upper value and a lower value around a voltage setting point. A second generator, which is a scaled-down replica of the first generator, produces a second signal that is indicative of an open-circuit voltage of the first generator. The driver circuit uses the second signal to set the voltage setting point.

Abstract: A radiofrequency-powered device such as a wireless passive sensor node, for instance, comprises a radiofrequency energy harvesting circuit configured to be coupled to an antenna to harvest radiofrequency energy captured by the antenna from a radiofrequency signal. The radiofrequency energy harvesting circuit is configured to be coupled to an energy storage component to store therein energy harvested via the radiofrequency energy harvesting circuit. The device comprises user circuitry configured to be supplied with energy harvested via the radiofrequency energy harvesting circuit and to operate in accordance with one of a plurality of configurations as a function of configuration data supplied thereto. A receiver circuit coupled to the radiofrequency energy harvesting circuit is configured to receive a configuration data signal modulating the radiofrequency signal and supply to the user circuitry configuration data extracted from the configuration data signal received.