Abstract: In described examples, an SoC includes at least two voltage domains interconnected with a communication bus. Detection logic in a first voltage domain determines when a voltage error occurs in a second voltage domain and isolates communication via the communication bus when a voltage error or a timing error is detected.

Abstract: An over-current protection device comprises first and second electrode layers and a PTC material layer laminated therebetween. The PTC material layer comprises a polymer matrix, a conductive ceramic filler, a carbon-containing conductive filler, and an inner filler. The polymer matrix comprises a fluoropolymer having a melting point higher than 150° C. The inner filler is selected from one of aluminum nitride, silicon carbide, zirconium oxide, boron nitride, graphene, aluminum oxide, or any mixtures thereof, and comprises 2-10% by volume of the PTC material layer. The over-current protection device is able to mitigate negative temperature coefficient (NTC) behavior after trip of device, and achieves high hold current and high endurable power.

Abstract: An ultra-low clamping voltage Surge Protection Module (SPM) is disclosed which utilizes a depletion mode MOSFET (D MOSFET). The SPM may be part of a circuit or a device and includes a primary protection stage and a secondary protection stage, with the D MOSFET being connected between the two stages. The SPM may include a single D MOSFET, dual D MOSFETs, or multiple D MOSFETs and the primary and secondary protection stages may be implemented with a number of different components. The SPM using D MOSFET(s) exhibits improved surge protection over circuits using inductors.

Abstract: An apparatus includes a connector port configured to be selectably connected with and disconnected from a peripheral device. A detector is configured to provide an output indicating the connection of the peripheral device with the connector port with a time delay between connection of the peripheral device with the connector port and outputting the signal. A data switch is operatively coupled with the detector and a communication pin of the connector port and to selectably enable and disable data communication between the communication pin and a computer board in response to the output of the detector. A power switch is operatively coupled with the detector, the power supply pin, and a DC power supply and is configured to selectably connect and disconnect the power supply and the power supply pin in response to the output of the detector.

Abstract: Embodiments of the present application disclose an adaptive bleeder control method and circuit, the method including: acquiring a peak characterizing voltage of a grid, wherein the peak characterizing voltage is a voltage value that characterizes a peak state among the grid characterizing voltages that are detected within a preset time and being scaled in proportion to the magnitude of the grid voltage; generating a switch control signal according to the peak characterizing voltage; performing switch control according to the switch control signal to generate a bleeder signal; and performing bleeder control on a light source device according to the bleeder signal to connect or disconnect a loop with a SCR in the light source device. In the present application, the dimming function of the light source device while preventing the bleeder current path from being constantly closed and reducing system efficiency may be implemented.

Abstract: A system for providing bi-directional power flow and power conditioning for high-voltage applications. The system including a normally-off four-quadrant power electronic switch having two gates and two normally-on junction field-effect transistor. The normally-off four-quadrant power electronic switch and the two normally-on junction field-effect transistors are coupled to one another in a bi-cascode configuration.

Abstract: A surge current suppression circuit includes a switch, a bypass resistor, a detection resistor, and a comparator. The switch is coupled to a first end of an energy storage capacitor in series, wherein a second end of the energy storage capacitor is coupled to a load and receives an input power source. The bypass resistor is coupled to the switch in parallel. The detection resistor is coupled to the switch in series to generate a detection voltage according to a capacitor current flowing through the energy storage capacitor. The comparator compares the detection voltage with a reference voltage to generate a control signal. When the detection voltage is greater than the reference voltage, the control signal controls the switch to be turned off. When the detection voltage is less than the reference voltage, the control signal controls the main switch to be turned on.

Abstract: A circuit to protect a digital input and output (I/O) terminal from an overvoltage applied externally to the digital I/O terminal. The circuit is arranged similar to a bootstrap switch such that a pass-device protects an output driver from an overvoltage applied to the digital I/O terminal and the output driver controls the operation of the pass-device, such as an N-channel metal-oxide semiconductor (NMOS) transistor. The circuit may include a capacitor and a diode coupled to the gate of the NMOS transistor. A digital zero from the output driver charges the capacitor. A digital one from the output driver causes the charged capacitor, coupled between source and the gate of the NMOS transistor, provides sufficient gate-source voltage to pass the digital one from the driver to the digital I/O terminal. The circuit further includes refresh circuitry configured to maintains the gate source voltage on the capacitor.

Abstract: A relay assembly that includes a relay, a bypass switch and a controller. The relay includes an electromechanical switch with an open state and a closed state. The bypass switch is operatively coupled in parallel with the electromechanical switch of the relay, and also has an open state and a closed state. The controller is operatively coupled to the relay and the bypass switch, and is configured to switch the bypass switch from the open state to the closed state, then switch the relay between the open state and closed state, and then switch the bypass switch back to the open state. In some cases, the bypass switch includes a TRIAC. The controller may be configured to maintain the bypass switch in the closed state for less than 100 milliseconds before switching back to the open state.

Abstract: A method performed by a computing system includes receiving a circuit design, the circuit design comprising a plurality of non-contiguous doped wells within a substrate and a plurality of resistor elements positioned above the plurality of non-contiguous doped wells such that each of the resistor elements is positioned above a different one of the plurality of non-contiguous doped wells and simulating performance of the circuit design with a first voltage applied to a first one of the plurality of resistor elements and a second voltage simultaneously applied to a second one of the plurality of resistor elements, the second voltage being different than the first voltage.

Abstract: A protection circuit intended to be connected between an electrical energy source and an overvoltage-sensitive device. A current limiting circuit and a current monitoring circuit are connected in series, a reference voltage generator circuit delivering a reference voltage, and a balancing circuit is intended to control the current monitoring circuit so that the voltage at a point of connection between the current limiting circuit and the current monitoring circuit is substantially equal to the reference voltage. An electrical measurement or power supply device including at least one such overvoltage protection circuit.

Abstract: One example discloses a current monitoring device, including: a sense impedance configured to receive a current to be monitored; an impedance divider, coupled to the sense impedance, and configured to convert the current to be monitored to a differential voltage to be monitored; a reference circuit configured to generate a differential reference voltage; a comparator coupled to the impedance divider and the reference circuit and configured to output a signal if the differential voltage to be monitored is different than the differential reference voltage; and wherein the reference circuit includes a comparator trimming circuit configured to vary the differential reference voltage to compensate for offset biases in the comparator.

Abstract: A hot plugging module power supply device, method and system are provided. When a hot plugging module is connected to a system in a hot plugging manner, a control unit transmits a first control signal to a signal processing unit. The signal processing unit forms a switch-on signal and transmits the switch-on signal to a switch unit, to gradually switch on the switch unit, to provide power to the hot plugging module. During the hot plugging module is supplied with power, when an overcurrent fault occurs in the hot plugging module, the control unit transmits a second control signal to the signal processing unit, and the signal processing unit forms a switch-off signal and transmits the switch-off signal to the switch unit, to immediately switch off the switch unit, to stop supplying power to the hot plugging module.

Abstract: A current limiting circuit configured to: before release of a touch between a second contact provided at a position where a terminal on a power receiving side in which a current flows at supply of DC power in an electrode that supplies the DC power touches before touching a first contact provided for the electrode at supply of the DC power and the terminal, decrease the current flowing into the terminal through the second contact; and avoid flowing a current in a case where the terminal is touching the first contact, and decrease the current flowing into the terminal through the second contact only in a case where the terminal is touching the second contact.

Abstract: An electrical circuit and a method for regulating current and providing a circuit breaker to the electrical circuit. The circuit includes a bidirectional cell including a set of forward switches for power flow during a forward mode of operation and a set of reverse switches for providing reverse power flow during a reverse mode of operation, a control inductor for controlling current flow during the reverse mode of operation, and a voltage clamping switch configured to provide the control inductor in the circuit during the reverse mode of operation and remove the control inductor from the circuit during the forward mode of operation. The circuit is operated in at least the reverse mode of operation.

Abstract: An electronic system, a host device and a control method are provided. The electronic system includes a host device, a cable and a slave device. The slave device receives supply power for operation. The cable is coupled between the host device and the slave device. The host device includes a data transmission interface circuit, a management circuit and a central processing unit. The data transmission interface circuit includes a reset circuit. The reset circuit is utilized for detecting whether the slave device has powered on and accordingly generating a simulated hot plug signal. The management circuit is utilized for determining a hot plug state between the host device and the slave device according to the simulated hot plug signal and accordingly generating a control signal. The central processing unit is utilized for establishing a link between the host device and the slave device according to the control signal.

Abstract: Circuits for protecting devices, such as gallium nitride (GaN) devices, and operating methods thereof are described. The circuits monitor a magnitude of the current in a device and reduce the magnitude of the current and/or shut down the device responsive to the magnitude of the current exceeding a threshold. These circuits safeguard devices from damaging operating conditions to prolong the operating life of the protected devices.

Abstract: An improved AC to DC conversion system consists of an electronic switch employed to disconnect the input of a prior art series voltage regulator circuit from a rectified AC mains power supply over a fraction of the period of the AC mains to reduce the power dissipated within the series regulator.

Abstract: An energy and power supply device includes an energy storage unit configured to store electrical energy, an output coupled to the energy storage unit and configured to provide an output electrical current to a load, and a current limiting system configured to selectively limit the output electrical current according to a current protection profile. The current protection profile includes a plurality of threshold currents and a plurality of corresponding threshold periods of time that facilitate providing the output electrical current according to a maximum variable current versus time function.

Abstract: A surge suppression device includes a micro electromechanical system (MEMS) switch electrically connected to a current path. Additionally, the surge suppression device includes a transient voltage suppression (TVS) device electrically connected in series to the MEMS switch. The surge suppression device is configured to protect electronic components from voltage surges or current surges.

Abstract: The present disclosure relates to a circuit providing protection against ground faults and over-voltages.

Abstract: A battery charger for charging a battery is disclosed. In one embodiment, the battery charger comprises an input for receiving a first voltage and for coupling to a positive terminal of the battery; a first transistor having a first gate, a first drain and a first source, wherein the first gate is for coupling to a charging signal for the battery and the first drain is coupled to the battery negative terminal and, the first transistor to cause energy to be transferred from the input into the battery when turned on; and a group of transistors coupled to the first transistor and the input to control when the first transistor is turned on, wherein the group of transistors comprises a second transistor having a second gate coupled to the input and coupled to a third transistor to turn off the third transistor after a delay occurs after the voltage on the input reaches a predetermined level, and further herein the third transistor causes the first transistor to turn on when the third transistor is turned off.

Abstract: A protective device is provided comprising a microswitch which is serially connected to a fuse or a circuit breaker, a current measuring unit, a storage unit, and a control unit. At least one current value range is stored on the storage unit. The current measuring unit is designed to measure current intensities in the protective device and to generate current values which represent the measured current intensities. The control unit is designed to process the current values, to open the microswitch if a current value lies in the current value range, and to reclose the microswitch after being opened. Also provided is a protective system for electrical circuits with multiple protective devices of the aforementioned type and to a method for controlling the protective system.

Abstract: A power generation system in an embodiment includes a power generator, a rectifying and smoothing circuit, a converter, a voltage measurement unit, and a switch. The power generator outputs AC power. The rectifying and smoothing circuit converts the AC power to DC power and smooths the DC power. The voltage measurement unit measures an average voltage of the AC power or a voltage of the smoothed DC power. The converter transforms the smoothed DC power. The switch is disposed between the rectifying and smoothing circuit and the converter, and becomes an ON state when the measured voltage becomes a reference voltage or higher.

Abstract: A device for reducing residual current in an electrical circuit, in particular an electrical low-voltage line, has a residual current sensor and a current measuring unit, wherein an output of the residual current sensor is connected to an input of the current measuring unit. The device has a voltage reducing unit, the voltage reducing unit is connected to an output of the current measuring unit, and the voltage reducing unit is designed to reduce the electrical voltage—subsequently applied to the device—depending on the height of the measured residual current in order to limit the measured residual current to a predeterminable value, in particular 30 mA.

Abstract: Two-transistor devices protect electrical circuits from sustained overcurrent conditions. Some cases provide normally-on depletion mode transistors biased into enhancement mode for lower impedance during normal current conditions, and then the transistors are biased into blocking depletion mode during sustained overcurrent conditions to block the current to the circuit. Optionally, the devices have only two terminals and require no auxiliary power to operate. Other cases provide protective circuitry for the transistors' gates, timing circuitry designed to ignore brief nuisance spikes, and/or timing circuitry to delay resetting the device until the current has returned to an acceptable level.

Abstract: An electric assembly includes a reverse conducting switching device and a rectifying device. The reverse conducting switching device includes transistor cells for desaturation configured to be, under reverse bias, turned on in a desaturation mode and to be turned off in a saturation mode. The rectifying device is electrically connected anti-parallel to the switching device. In a range of a diode forward current from half of a maximum rating diode current of the switching device to the maximum rating diode current, a diode I/V characteristic of the rectifying device shows a voltage drop across the rectifying device higher than a saturation I/V characteristic of the switching device with the transistor cells for desaturation turned off and lower than a desaturation I/V characteristic of the switching device with the transistor cells for desaturation turned on.

Abstract: A wind power generation system according to the present invention includes: a DC bus; a plurality of feeders connected to the DC bus for transmitting DC powers to the DC bus; a plurality of wind power generators; a plurality of AC/DC converters connected one by one to each of the wind power generators for converting AC powers generated by the connected wind power generators, into DC powers, and outputting the DC powers to the feeders; and a DC breaker and a diode, which serve as a current limiting unit installed on each of the feeders for preventing a DC current from flowing from the DC bus into the feeder.

Abstract: The disclosure is related to a voltage-source multi-level converter including a phase unit. The phase unit includes first and second bridge arms, each includes modules and reactor connected in series. In the first bridge arm, a first terminal of first reactor is connected to alternating-current terminal of the phrase unit, a second terminal thereof is connected to a first terminal of the first modules, and second terminal of the first modules is connected to first DC terminal of the phrase unit. In the second bridge arm, a first terminal of the second reactor is connected to the alternating-current terminal, a second terminal thereof is connected to a first terminal of the second modules, and a second terminal of the second modules is connected to second DC terminal of the phrase unit. Then, a parallel fault shunt circuit is connected between the second terminals of the first and second reactors.

Abstract: The invention relates to a measuring resistor (1), in particular a low-resistance current-measuring resistor, comprising two terminal parts (2, 3) that consist of a conductor material for introducing and discharging a current, and a resistor element (4) that consists of a resistor material, wherein the resistor element (4) is arranged between the two terminal parts (2, 3) in the direction of the current and current flows through the resistor element (4). According to one variant of the invention, the measuring resistor (1) has several pairs of voltage-measuring contacts (7) for measuring the voltage falling across the resistor element (4) in order to be able to compensate metrologically for inhomogeneities in the current density.

Abstract: An electronic device is provided. The device includes a first connector configured to couple with a second connector and including a plurality of contacts separated from each other, and a processor configured to detect an incomplete connection between the first connector and the second connector when an electric current does not flow through at least one of the contacts.

Abstract: A control circuit includes a set of alternating-current (AC) power receiver terminals, a rectification unit, a transistor, a switch, a detection unit, a comparison unit and a logic control circuit. The AC power receiver terminals receive and send external AC power to the rectification unit. The rectification unit outputs an operation voltage accordingly. The transistor is coupled between the rectification unit and the switch. The detection unit is coupled to the rectification unit to generate a first detection voltage and a second detection voltage according to the operation voltage. When the first detection signal is equal to the second detection signal, the comparison unit sends a comparison signal. The logic control circuit turns on the transistor and the switch if the comparison signal still has not been received after a predetermined time interval has elapsed.

Abstract: A surface mountable over-current protection device comprises a PTC material layer, first and second conductive layers, left and right electrodes, left and right conductive members, and left and right insulating members. The PTC material layer comprises a left notch at a left end and a right notch at a right end. The first conductive layer comprises a primary portion disposed on an upper surface of the PTC material layer and a secondary portion extending over the left notch, and the second conductive layer comprises a primary portion disposed on a lower surface of the PTC material layer and a secondary portion extending over the underside of the right notch. The left conductive member connects to the left electrode and the first conductive layer and isolates from the second conductive layer. The right conductive member connects to the right electrode and the second conductive layer and isolates from the first conductive layer.

Abstract: An electronic device having at least a first HEMT transistor and bias circuit able to at least reverse bias the first HEMT transistor by applying an electric voltage VSD of a positive value between a source of the first HEMT transistor and a drain of the first HEMT transistor. The first HEMT transistor is able to be ON when a value of an electric voltage VGD between a gate of the first HEMT transistor and the drain of the first HEMT transistor is higher than a value of a threshold voltage Vth of the first HEMT transistor. The electronic device has, during a forward biasing, a behavior similar to that of a forward biased or reverse biased Zener diode.

Abstract: A board assembly includes a first board. The first board includes a first board connector that is configured to connect to a first baseboard connector receptacle included on a baseboard and a first board component coupled to the first board connector through the first board. The board assembly also includes a second board that is movably coupled to the first board by at least one floating coupling that allows the second board to move relative to the first board. The second board includes a second board connector that is configured to connect to a second baseboard connector receptacle included on the baseboard and a second board component coupled to the second board connector through the second board.

Abstract: A direct current (DC) power system includes a plurality of energy sources supplying power to a plurality of loads via a DC bus having at least one positive rail. The DC bus includes two DC bus subsections and a DC bus separator coupled between the two DC bus subsections. The DC bus separator includes a controllable switch with at least one of its terminals coupled with a terminal of an inductor to provide a current path between the two DC bus subsections during normal operation via the inductor. The controllable switch is switched off to break the current path when a fault on the positive rail is detected. Furthermore, the DC bus separator includes a diode connected in parallel to the inductor and arranged to provide a circulating current path to dissipate an inductor current in the inductor when the controllable switch is switched off.

Abstract: An AC inrush current testing device is disclosure. The AC inrush current testing device includes a grid voltage peak point calculator, a grid voltage period and timing detector, a switch, an autotransformer, and a main relay. The grid voltage period and timing detector is connected to an AC power source and the grid voltage peak point calculator. A movable contact of the switch is connected to the AC power source. A first winding of the autotransformer is connected to the AC power source, a second winding of the autotransformer, and a first stationary contact of the switch. A third winding of the autotransformer is connected to a second stationary contact of the switch and the second winding. The main relay is electrically connected to the grid voltage peak point calculator, the second winding, and the third winding. A method for testing AC inrush current is further disclosed.

Abstract: A commutating circuit breaker that works by progressively inserting increasing resistance into a circuit. This is done via physical motion of a shuttle that is linked into the circuit by at least one set of sliding electrical contacts on the shuttle (“shuttle electrodes”) that connect the power through the moving shuttle to a sequence of different resistive paths with increasing resistance; the motion of the shuttle can be either linear or rotary. A feature of the commutating circuit breaker is that at no point are the shuttle electrodes separated from the matching stationary stator electrodes so as to generate a powerful arc, which minimizes damage to the electrodes. Instead, the current is commutated from one resistive path to the next with small enough changes in resistance at each step that arcing can be suppressed. The variable resistance can either be within the moving shuttle, or the shuttle can comprise a commutating shuttle that moves the current over a series of stationary resistors.

Abstract: An input redundant circuit according to the present disclosure may include: a core power supply unit; a first input port connected to a first input voltage; a second input port connected to a second input voltage; a relay unit connected to the first input port and the second input port to supply one of the first input voltage and the second input voltage to the core power supply unit; and a surge current limiting unit coupled to the relay unit, configured to limit a surge current generated when the relay unit is switched between the first input voltage and the second input voltage.

Abstract: Apparatus and methods for selective protection of an electrical load from disturbances on an input power line. A power protection circuit includes a selectively variable inrush current limiting circuit and a switch for disconnecting the input power line from the load. A control circuit determines that the electrical load is in a first operational state, such as a standby mode or normal operation, or a second operational state, such as full operation at rated current. The power protection circuit provides variable inrush current limiting to the electrical load in response to a first category of disturbances when the electrical load is in the first operational state. The power protection circuit inhibits disconnecting the electrical load in response to a second category of disturbances when the electrical load is in the second operational state. Species of selectively variable current limiting circuits are also described.

Abstract: A method of protecting a speaker from thermal damage includes determining a first load current through a first resistor that is coupled to the speaker. The method also includes converting the first load current to a digital value using a second load current through a second resistor as a reference input. The second resistor is part of a circuit that reduces an effect of a temperature coefficient of resistance of the first resistor. The method also includes comparing the digital value of the first load current to a threshold value. The method further includes, responsive to the first load current being larger than the threshold value, generating an instruction to take an action to protect the speaker.

Abstract: An input redundant circuit according to the present disclosure may include: a core power supply unit; a first input port connected to a first input voltage; a second input port connected to a second input voltage; a relay unit connected to the first input port and the second input port to supply one of the first input voltage and the second input voltage to the core power supply unit; and a surge current limiting unit coupled to the relay unit, configured to limit a surge current generated when the relay unit is switched between the first input voltage and the second input voltage.

Abstract: An apparatus for the location-dependent configuration of a device is coupled to the apparatus. The apparatus has first and second power supply terminals, a locating terminal for locating the apparatus on the basis of a voltage applied to the locating terminal, and a configuration device for configuring the device on the basis of the voltage that is applied to the locating terminal. The first power supply terminal and the locating terminal are formed by the same terminal.

Abstract: A control circuit for indirectly limiting a load current which flows through a controllable semiconductor component. The control circuit controls the controllable semiconductor component based upon a measured and/or a calculated load-current-dependent power loss of the semiconductor component. The control circuit can also control the controllable semiconductor component based upon a measured and/or a calculated load-current-dependent component temperature of the controllable semiconductor component. A charging circuit includes a controllable semiconductor component for limiting a load current and has a control circuit in accordance with the invention. A motor vehicle includes an on-board electrical power supply system having a charging circuit in accordance with the invention.

Abstract: In one form, the invention relates to a transmission device for transmitting an electric current to a component of a steering wheel of a motor vehicle, including a rotor which is to be arranged on the steering wheel such that it is rotatable along with the steering wheel; a stator which is to be arranged on a component of the vehicle that is stationary as compared to a rotary movement of the steering wheel; at least one conductor element by which the rotor is electrically connected with the stator; and a temperature determination device for determining the temperature of the conductor element or in the region of the conductor element. In another form, the invention also relates to a method for transmitting an electric current to a component of a steering wheel of a motor vehicle.

Abstract: Aspects of the disclosure pertain to a system and method for providing dynamic charge current based on maximum expansion card power. Dynamic monitoring of overall power usage by an expansion card is performed. Based on the dynamic monitoring, power consumption of a charging circuit of the card is dynamically adjusted for maintaining the overall power consumption of the expansion card at or below a pre-determined power limit (e.g., at or below an expansion slot power limit). Further, based on the dynamic monitoring, an amount of charging current provided by a current limiting device of the charging circuit to an energy storage device of the charging circuit is dynamically adjusted.

Abstract: An intrinsically safe redundant regulator circuit includes a plurality of voltage limiting regulators between a regulated rail and a ground rail. Each of the plurality of voltage limiting regulators includes: (i) a shunt regulator component configured to clamp a voltage across the regulated rail and the ground rail to a safety clamp voltage value; and (ii) one or more components, where a property of each of the one or more components is selected to configure the safety clamp voltage value.

Abstract: Various aspects provide for incorporating a VSDM into a substrate to create an ESD-protected substrate. In some cases, a VSDM is incorporated in a manner that results in the ESD-protected substrate meeting one or more specifications (e.g., thickness, planarity, and the like) for various subsequent processes or applications. Various aspects provide for designing a substrate (e.g., a PCB) incorporating a VSDM, and adjusting one or more aspects of the substrate to design a balanced, ESD-protected substrate. Certain embodiments include molding a substrate having a VSDM layer into a first shape.

Abstract: An integrated power distribution system utilizes a subsea power distribution hub that receives high voltage electricity through an umbilical from a host surface facility. The subsea power distribution hub steps down the high voltage electricity and distributes the appropriate electrical power supply to multiple components of a subsea production system (e.g., in-well pumps, subsea booster pumps, subsea processing units, subsea valves, and subsea sensors) via jumpers. The integrated subsea power distribution system can be utilize to supply electrical power to all of the required process components of the subsea production system from the in-well completion to the surface host facility.

Abstract: A power supply controller includes a switch circuit to be provided between the power source and the power supply path, the switch circuit switches the power supply from the power source to the load between on and off, and a power-supply-path protection circuit. The power-supply-path protection circuit controls switching operation of the switch circuit according to a power-supply command signal that commands to start or terminate the power supply to the load, to calculate a temperature of the power-supply path, and if the calculated temperature reaches a predetermined upper limit, to inhibit the switch circuit from the power supply, thereby protecting the power-supply path. In a case where the power supply by the switch circuit is inhibited, if the temperature of the power supply path decreases to a predetermined threshold temperature, the power-supply-path protection circuit removes inhibition of the power supply by the switch circuit.