Abstract: A fuel cell power system and a method of starting a fuel cell power system. The fuel cell power system includes a fuel cell system having one or more voltage outputs, one or more DC/DC converters each having an output and an input, the input being connectable to the voltage outputs of the fuel cell system, a DC voltage link connectable to the output of the one or more DC/DC converters, and a local load connectable to the DC voltage link. In the system, the local load is adapted to draw power from the fuel cell system to decrease the voltage of the fuel cell system.

Abstract: A drive device for driving a voltage-controlled semiconductor element. The drive device includes: a drive circuit connected to the gate of the semiconductor element via a gate resistor; a delay circuit connected to the drive circuit, for delaying a drive signal output from the drive circuit until a gate voltage of the semiconductor element enters a Miller effect period, which is a period during which the gate voltage transitionally changes, the gate voltage having temperature dependency on a chip temperature of the semiconductor element; a one-shot circuit connected to the delay circuit, for outputting a pulse signal with a pulse width shorter than the Miller effect period; a comparator that compares the gate voltage with a reference voltage; and an AND circuit that outputs an overheat detection signal in response to the gate voltage exceeding the reference voltage.

Abstract: A power supply apparatus includes a switching circuit including a switcher, a first input terminal, a second input terminal, and an output terminal, the first input terminal is configured to receive a first voltage provided by a first power supply, the second input terminal is configured to receive a second voltage provided by a second power supply, and the switcher is configured to control the output terminal to be connected to the first input terminal or control the output terminal to be connected to the second input terminal; and a converting circuit including an input terminal connected to the output terminal of the switching circuit, an output terminal connected to an electrical device, and the converting circuit is configured to receive the first or the second voltage, convert the received first second voltage into a third voltage, and output the third voltage through the output terminal of the converting circuit.

Abstract: An example method performed for a circuit path includes: receiving signals in the circuit path; and controlling states of the signals in the circuit path based on skews produced by circuits electrically connected in series in the circuit path. The states are controlled by inverting or not inverting the signals in the circuit path so that skews produced by different circuits in the circuit paths at least partially cancel.

Abstract: Circuits, controllers, and techniques are provided for reducing non-linearities in a phase rotator. A card include first transmit (Tx) component configured to connect to a second receive (Rx) component in a second card; a first Rx component configured to connect to a second Tx component in the second card; a single Phase-Locked Loop (PLL) circuit connected to both the first Tx component and the first Rx component; and a control circuit configured to compensate for differences between i) the first Tx component and the second Rx component, and ii) the first Rx component and the second Tx component.

Abstract: An oscillation device, such as a frequency standard or “atomic clock”, is disclosed. The device comprises: a system capable of undergoing transitions between different energy states, the transitions defining at least a first resonance frequency and a second resonance frequency; an excitation device arranged to induce the system to undergo such transitions; a detection device arranged to detect a response of the system caused by the excitation device, to produce an output; and a controller arranged to receive the output, to control the excitation device to stimulate said transitions, and to obtain signals corresponding to at least the first and second resonance frequencies; wherein the controller is also arranged to process the obtained signals to produce a corrected output signal that is compensated against at least one influence on the resonance frequencies of the system.

Abstract: A power supply system including: a first voltage subsystem including a first battery connected to a load via a relay; a second voltage subsystem including a second battery, the second battery having a lower voltage than the first battery; and a DC/DC converter disposed between the first voltage subsystem and the second voltage subsystem, wherein before switching the relay to be closed, the DC/DC converter is configured to: provide a lower voltage than a voltage of the second battery to the first voltage subsystem; subsequently provide the voltage of the second battery to the first voltage subsystem; and subsequently increase the voltage of the second battery to be equal to a voltage of the first battery and provide the voltage of the second battery to the first voltage subsystem.

Abstract: A pulse width modulation (PWM) method for converting an input signal into an output PWM signal includes the following steps: generating a first linear periodic wave and a second linear periodic wave which are triangle waves or sawtooth waves, wherein the amplitude of the first linear periodic wave is greater than the amplitude of the second linear periodic wave; determining whether the level of the input signal is lower than a light load threshold; when the level of the input signal is lower than the light load threshold, generating the output PWM signal according to a comparison between the input signal and the second linear periodic wave; and when the level of the input signal is higher than the light load threshold, generating the output PWM signal according to a comparison between the input signal and the first linear periodic wave.

Abstract: The present invention provides a drive module for a GaN transistor, including: a first pull-down transistor and a gate ringing and overshoot suppression unit, where the gate ringing and overshoot suppression unit and a first end of the first pull-down transistor are directly or indirectly connected to a gate of the GaN transistor, the gate ringing and overshoot suppression unit is connected between a second end of the first pull-down transistor and the ground; the gate ringing and overshoot suppression unit is configured to: when a gate voltage of the GaN transistor drops, control the release of a gate charge of the GaN transistor with a first impedance if the gate voltage is higher than a specified threshold; and control the release of the gate charge of the GaN transistor with a second impedance if the gate voltage is less than the specified threshold, where the first impedance is less than the second impedance.

Abstract: A photovoltaic system, an optimizer, a controller, a computer program product, a computer-readable storage medium, a chip, and a method for adjusting a working state of an optimizer are provided. The photovoltaic system includes a photovoltaic panel and an optimizer. The optimizer includes a controller, a first output port, and a second output port. The controller is configured to detect an electrical signal parameter between the first output port and the second output port. The controller is configured to adjust a working state of the optimizer from a no-output state or a limited-output state to an unlimited-output state when the electrical signal parameter changes. In the photovoltaic system, the working state can be adjusted without using an unlocking apparatus, so that an implementation is simple, and costs are reduced.

Abstract: An output driver is provided. The output driver includes: a pull-up driver connected between an output power supply voltage and an output node, and configured to pull up a voltage at the output node based on a pull-up driving signal and a pull-up reference voltage; a pull-down driver connected between the output node and a ground voltage, and configured to pull down the voltage at the output node based on a pull-down driving signal and a pull-down reference voltage; and a reference voltage compensation circuit configured to perform a short operation during transitions of the pull-up driving signal and the pull-down driving signal, wherein the short operation includes electrically connecting any one or any combination of the pull-up reference voltage to the ground voltage, and the pull-down reference voltage to the output power supply voltage.

Abstract: A laser system involving coupled distributed resonators disposed serially, with the lasing gain medium located in the main resonator and the output of that resonator being directed into a free space resonator, such that the main resonator output mirror is effectively the free space resonator. The distributed resonators end mirrors are retroreflectors. Interference occurs between light traveling towards the remote mirror of the free space resonator and light reflected therefrom, generating regions of high reflectivity. The coupling of the free space resonator to the regions of high reflectivity of the free space resonator enables the first resonator to lase efficiently, even though the true reflectivity of the main resonator output mirror outside of those regions is insufficient to enable efficient lasing, if at all. This coupled resonator structure enables lasing to occur with a high field of view and the high gain engendered by the high reflectivity regions.

Abstract: Systems and methods are described herein for controlling a switch. In some embodiments, circuitry may detect a voltage across the switch. A current reference signal may be generated based on the voltage across the switch. The switch may be controlled based, at least in part, on the current reference signal.

Abstract: A bootstrapped switch includes a sampling transistor, a bootstrapped circuit, and a buffer circuit. The sampling transistor is configured to be selectively turned on according to a level of a control node, in order to transmit an input signal from a first terminal of the sampling transistor to a second terminal of the sampling transistor, in which a body of the sampling transistor is configured to receive a buffer signal. The bootstrapped circuit is configured to pull up the level of the control node, such that a constant voltage difference is present between the control node and the first terminal of the sampling transistor during a turn-on interval of the sampling transistor. The buffer circuit is configured to generate the buffer signal according to the input signal.

Abstract: A driving device comprises a first complementary metal-oxygen-semiconductor circuit and a first comparator. The first complementary metal-oxygen-semiconductor circuit is configured for outputting a power signal or a pull-down signal according to the first input signal. The first comparator comprises a first non-inverting input terminal and a first inverting input terminal. The first non-inverting input terminal is coupled to the first complementary metal-oxygen-semiconductor circuit, and is configured to receive the power signal or the pull-down signal. The first inverting input terminal is configured for receiving a first reference signal, and the first comparator is configured to compare one of the power signal and the pull-down signal and the first reference signal to provide a first driving signal.

Abstract: A switching circuit comprises a main switch element having a gate as a control input; and a ring oscillator connected as a driver circuit to the gate to drive the main switch via the gate. The basic circuit is used to build various components which have the property that they can work at very high frequencies.

Abstract: A comparator circuit according to this embodiment includes: a comparator element configured to output a matching signal indicating whether or not a value of a first input signal matches a value of a second input signal; a flip-flop circuit configured to hold a data of a data input terminal based on a comparator clock signal and configured to output an enable signal for stopping an operation of the comparator element; and an internal signal generation circuit configured to output an internal signal to the data input terminal based on the matching signal and an output signal output from the flip-flop circuit.

Abstract: A semiconductor device includes a first switch and a first driver. The first switch selects and outputs one of a power supply potential and a generated potential as a first switch output potential based on a synchronization signal from a transmission circuit and a delayed signal delayed from the synchronization signal. The first driver charges a gate of a bipolar transistor element based on the synchronization signal of the transmission circuit and the first switch output potential.

Abstract: An apparatus includes a transistor coupled to a load through an output terminal of a load switch IC, a gate drive circuit connected to a gate of the transistor, wherein the gate drive circuit is configured such that in a short circuit event, a voltage on the gate of the transistor is gradually reduced, and wherein as a result of reducing the voltage on the gate of the transistor gradually, a negative voltage occurring at the output terminal of the load switch IC is minimized.

Abstract: A power supply system includes an alternating current sweep unit and a first power supply circuit, and each of a first U-phase battery string, a first V-phase battery string, a first W-phase battery string, and a first battery string includes a plurality of battery circuit modules connected in series, and each of the battery circuit modules includes a battery, output terminals, a first switch, and a second switch.