Abstract: A sensor includes a first sensing element configured to sense a parameter and generate a first sensing element output signal indicative of the parameter, a first front end element configured to receive the first sensing element output signal and to generate a first front end signal, a second sensing element configured to sense the parameter and generate a second sensing element output signal indicative of the parameter, a second front end element configured to receive the second sensing element output signal and to generate a second front end signal, a difference block configured to receive the first and second front end signals and generate a difference signal indicative of a difference between the first and second front end signals, an absolute value block configured to receive the difference signal and generate an absolute difference signal indicative of an absolute value of the difference signal, and an offset comparator configured to compare the absolute difference signal to an offset threshold to detect

Abstract: A system of fuel cells for an aircraft including a plurality of fuel cells, a hydrogen circuit, a cooling circuit and a first air circuit configured to supply oxygen to a first subset of fuel cells having at least two cells. The first air circuit includes an air flow restrictor at each fuel cell inlet of the first subset and configured to distribute the air between the fuel cells of the first subset, and an outlet valve connected to the outlet of the fuel cells of the first subset, the opening of the outlet valve being controlled by a computer as a function of an electrical power that is to be produced by the fuel cells of the first subset. The use of the same air circuit to supply oxygen to several fuel circuits makes it possible to limit the bulk of the fuel cells system.

Abstract: An autonomous propeller propulsion system for an aircraft. The autonomous system comprises a chassis with first attachment systems which engage with second attachment systems of the wing to ensure detachable attachment of the autonomous system, a fuel cell attached to the chassis, an electric motor attached to the chassis and having an output shaft, a propshaft rotated by the output shaft, a propeller attached to the propshaft, a controller converting an electric current delivered by the fuel cells into an electric current delivered to the electric motor, a hydrogen feed duct and an air feed duct, a set of auxiliary equipment, and a first connection arrangement, which connects with a second connection arrangement of the aircraft.

Abstract: A system of fuel cells for an aircraft includes a plurality of fuel cells, a hydrogen circuit, an air circuit, and a first cooling circuit configured to cool a first subset of cells including at least two cells. The first cooling circuit includes a computer-controlled device for mixing a first liquid coolant at a first temperature with a second liquid coolant at a second temperature lower than the first temperature to obtain a liquid coolant having a target temperature, a liquid coolant restrictor configured to distribute the liquid coolant between the cells of the first subset, and an outlet valve, the opening of which is controlled by the computer as a function of the cooling needs of the cells of the first subset. The use of a cooling circuit to cool several fuel circuits makes it possible to limit the bulk of the fuel cells system.

Abstract: A system of fuel cells for an aircraft includes a plurality of fuel cells, a hydrogen circuit, an air circuit, and a first cooling circuit configured to cool a first subset of cells including at least two cells. The first cooling circuit includes a computer-controlled device for mixing a first liquid coolant at a first temperature with a second liquid coolant at a second temperature lower than the first temperature to obtain a liquid coolant having a target temperature, a liquid coolant restrictor configured to distribute the liquid coolant between the cells of the first subset, and an outlet valve, the opening of which is controlled by the computer as a function of the cooling needs of the cells of the first subset. The use of a cooling circuit to cool several fuel circuits makes it possible to limit the bulk of the fuel cells system.

Abstract: A system of fuel cells for an aircraft including a plurality of fuel cells, a hydrogen circuit, a cooling circuit and a first air circuit configured to supply oxygen to a first subset of fuel cells having at least two cells. The first air circuit includes an air flow restrictor at each fuel cell inlet of the first subset and configured to distribute the air between the fuel cells of the first subset, and an outlet valve connected to the outlet of the fuel cells of the first subset, the opening of the outlet valve being controlled by a computer as a function of an electrical power that is to be produced by the fuel cells of the first subset. The use of the same air circuit to supply oxygen to several fuel circuits makes it possible to limit the bulk of the fuel cells system.

Abstract: An autonomous propeller propulsion system for an aircraft. The autonomous system comprises a chassis with first attachment systems which engage with second attachment systems of the wing to ensure detachable attachment of the autonomous system, a fuel cell attached to the chassis, an electric motor attached to the chassis and having an output shaft, a propshaft rotated by the output shaft, a propeller attached to the propshaft, a controller converting an electric current delivered by the fuel cells into an electric current delivered to the electric motor, a hydrogen feed duct and an air feed duct, a set of auxiliary equipment, and a first connection arrangement, which connects with a second connection arrangement of the aircraft.

Abstract: A DC-DC converter circuit including at least: a first step down converter having a first pair of switching devices in a half bridge configuration. A second step down converter includes a second pair of switching devices in a half bridge configuration. The first and second step down converters are connected in parallel to an output node connected to an output coil and receive command signals. A feedback loop includes a synchronization module receiving the gate control signals of high side switching devices and adjusts as a function of the gate control signals a delay in a signal path from the command signal to each gate control signal of the high side switching device to synchronize the gate control signals.

Abstract: A DC-DC converter circuit including at least: a first step down converter having a first pair of switching devices in a half bridge configuration. A second step down converter includes a second pair of switching devices in a half bridge configuration. The first and second step down converters are connected in parallel to an output node connected to an output coil and receive command signals. A feedback loop includes a synchronization module receiving the gate control signals of high side switching devices and adjusts as a function of the gate control signals a delay in a signal path from the command signal to each gate control signal of the high side switching device to synchronize the gate control signals.

Abstract: An electronic device includes first and second transistors coupled in series between first and second source voltage levels. An inductor is coupled between a node coupling the first and second transistors and a load. Control logic is operative to generate control pulses operative to switch the first and second transistors. The controller generates the control pulses as a continuous stream of control pulses in a continuous conduction mode, and skips generation of some control pulses in a discontinuous conduction mode in response to a pulse skipping signal. A pulse skipping circuit is operative to generate a sense voltage as a function of an inductor current in the inductor, compare the sense voltage to ground, and generate a pulse skipping signal to the control logic when the sense voltage is below ground.

Abstract: An electronic device includes first and second transistors coupled in series between first and second source voltage levels. An inductor is coupled between a node coupling the first and second transistors and a load. Control logic is operative to generate control pulses operative to switch the first and second transistors. The controller generates the control pulses as a continuous stream of control pulses in a continuous conduction mode, and skips generation of some control pulses in a discontinuous conduction mode in response to a pulse skipping signal. A pulse skipping circuit is operative to generate a sense voltage as a function of an inductor current in the inductor, compare the sense voltage to ground, and generate a pulse skipping signal to the control logic when the sense voltage is below ground.

Abstract: A DC-DC converter transitions between continuous conduction mode (CCM) and discontinuous conduction mode (DCM) without causing any overshoot or undershoot deviation output voltage. The DC-DC converter operates in a PWM mode in CCM. During DCM, it skips PWM pulses when a sustained negative current is detected in an output inductor. The current sensing is achieved by sampling and integrating a voltage, the sign of which is inverse to current direction. The sample and hold and integrator circuits are small, simple, and scale to high frequencies. The pulse skipping circuit automatically adjusts the duty cycle of power pulses to force a zero inductor current at the end of each pulse.

Abstract: A power conversion circuit uses smaller, cheaper, and faster analog and digital circuits, e.g., buffers, comparators, and processing circuits, to provide the information necessary to control a multilevel power converter faster, cheaper, and with a smaller footprint than conventional techniques. For example, a current detection circuit indirectly measures a direction of a current through an inductor connected between midpoint node and an output node of a multilevel power converter based on comparisons between voltages associated with the multilevel power converter. A capacitor voltage detection detects a capacitor voltage across the flying capacitor to generate a logic signal based on a comparison between the capacitor voltage and a first reference voltage.

Abstract: A multi-mode, dynamic, DC-DC converter supplies a dynamically varying voltage, as required, from a battery to an RF power amplifier (PA). In envelope tracking mode, a fast DC-DC converter generates a dynamic voltage that varies based on the amplitude envelope of an RF signal, and regulates the voltage at the PA. A slow DC-DC converter generates a steady voltage and regulates the voltage across a link capacitor. The fast and slow converters are in parallel from the view of the PA, and the link capacitor is between the fast converter and the PA. Because different nodes are regulated, no current sharing is possible between the converters. The link capacitor boosts the dynamic voltage level, allowing a maximum dynamic voltage at the load to exceed the battery voltage. In power level tracking mode, the fast converter is disabled and the link capacitor is configured to be in parallel with the load.

Abstract: A DC-DC converter transitions between continuous conduction mode (CCM) and discontinuous conduction mode (DCM) without causing any overshoot or undershoot deviation output voltage. The DC-DC converter operates in a PWM mode in CCM. During DCM, it skips PWM pulses when a sustained negative current is detected in an output inductor. The current sensing is achieved by sampling and integrating a voltage, the sign of which is inverse to current direction. The sample and hold and integrator circuits are small, simple, and scale to high frequencies. The pulse skipping circuit automatically adjusts the duty cycle of power pulses to force a zero inductor current at the end of each pulse.

Abstract: A multi-mode, dynamic, DC-DC converter supplies a dynamically varying voltage, as required, from a battery to an RF power amplifier (PA). In envelope tracking mode, a fast DC-DC converter generates a dynamic voltage that varies based on the amplitude envelope of an RF signal, and regulates the voltage at the PA. A slow DC-DC converter generates a steady voltage and regulates the voltage across a link capacitor. The fast and slow converters are in parallel from the view of the PA, and the link capacitor is between the fast converter and the PA. Because different nodes are regulated, no current sharing is possible between the converters. The link capacitor boosts the dynamic voltage level, allowing a maximum dynamic voltage at the load to exceed the battery voltage. In power level tracking mode, the fast converter is disabled and the link capacitor is configured to be in parallel with the load.

Abstract: A power conversion circuit uses smaller, cheaper, and faster analog and digital circuits, e.g., buffers, comparators, and processing circuits, to provide the information necessary to control a multilevel power converter faster, cheaper, and with a smaller footprint than conventional techniques. For example, a current detection circuit indirectly measures a direction of a current through an inductor connected between midpoint node and an output node of a multilevel power converter based on comparisons between voltages associated with the multilevel power converter. A capacitor voltage detection detects a capacitor voltage across the flying capacitor to generate a logic signal based on a comparison between the capacitor voltage and a first reference voltage.