1633 results about "Current switch" patented technology

Provided is a current-source push-pull DC-DC converter using an active clamp circuit for reusing energy of leakage inductances by not only diodes on a secondary side of a transformer being zero-current switched using a series-resonant full-wave rectifier, but also the active clamp circuit on a primary side of the transformer, which provides a discharge path of the energy stored in the leakage inductances, increases power conversion efficiency even for a wide input voltage range and reduces a switch voltage stress as compared to a conventional current-source push-pull circuit by operating even for a duty ratio below 0.5 by flowing a current of an input inductor through capacitors of the active clamp circuit when both main switches are off.

Systems and methods for gathering troubleshooting information through one or more networks are disclosed. In one embodiment, the method comprises a switch port configured to receive a frame that has information added by another switch. As the frame traverses the network, control logic in the switch adds additional information into the frame from the current switch.

A scanning architecture that makes it possible to update only those ultrasonic transducer subelements of a mosaic transducer array that change from view to view. The configuration of the switch matrix is fully programmable. The switch matrix includes access switches that connect subelements to bus lines and matrix switches that connect subelements to subelements. Each subelement has a unit switch cell associated therewith, each unit switch cell comprising at least one access switch, at least one matrix switch, and addressing and control logic. Optionally, each unit switch cell also includes latches for storing the future switch states of the switches to be programmed. The switches themselves have memory for storing their current switch states.

A PWM controller has a line voltage input that allows using a start-up resistor for both start-up and power-limit compensations so that it can save the power consumption, ease the PCB layout, and shrink the power supply size. In the integrated circuit, a current switch used for both start-up and line voltage sensing is composed of a diode and a switch transistor. A current multiplier is used to improve the precise by canceling the impact of the integrated resistor's absolute value, which is composed of a transistor loop, a constant current and a reference current. Thus, by properly selecting the value of the start-up resistor, an identical output power limit for low line and high line voltage input can be achieved.

A scanning architecture that makes it possible to update only those ultrasonic transducer subelements of a mosaic transducer array that change from view to view. The configuration of the switch matrix is fully programmable. The switch matrix includes access switches that connect subelements to bus lines and matrix switches that connect subelements to subelements. Each subelement has a unit switch cell associated therewith, each unit switch cell comprising at least one access switch, at least one matrix switch, and addressing and control logic. Optionally, each unit switch cell also includes latches for storing the future switch states of the switches to be programmed. The switches themselves have memory for storing their current switch states.

An apparatus and a method for a bias modulator using a Zero Current Switching (ZCS) are provided. The bias modulator includes a Pulse Width Modulation (PWM) signal generator for converting an input envelope signal to a PWM signal; a PWM / ZCS converter for calculating the number of ZCS control signals to be provided within an on-time duration of the PWM signal and generating at least one ZCS control signal according to the number of the ZCS control signals; and a ZCS switching regulator for generating a bias current according to the ZCS control signal.

One embodiment of the present invention includes a multi-state current-switching magnetic memory element having a stack of magnetic tunneling junction (MTJ) separated by a non-magnetic layer for storing more than one bit of information, wherein different levels of current applied to the memory element cause switching to different states.

One embodiment of the present invention includes a an embodiment of the present invention includes a non-volatile current-switching magnetic memory element including a bottom electrode; a pinning layer formed on top of the bottom electrode; a fixed layer formed on top of the pinning layer; a tunnel layer formed on top of the pinning layer; a first free layer formed on top of the tunnel layer; a granular film layer formed on top of the free layer; a second free layer formed on top of the granular film layer; a cap layer formed on top of the second layer; and a top electrode formed on top of the cap layer.

A low leakage current switch device (110) is provided which includes a GaN-on-Si substrate (11-13) covered by a passivation surface layer (43) in which a T-gate electrode with sidewall extensions (48) is formed and coated with a conformal passivation layer (49) so that the T-gate electrode sidewall extensions are spaced apart from the underlying passivation surface layer (43) by the conformal passivation layer (49).

An integrated switch matrix for reconfiguring subelements of a mosaic sensor array to form elements. The configuration of the switch matrix is fully programmable. The switch matrix includes access switches that connect subelements to bus lines and matrix switches that connect subelements to subelements. Each subelement has a unit switch cell comprising at least one access switch, at least one matrix switch, a respective memory element for storing the future state of each switch, and a respective control circuit for each switch. The access and matrix switches are of a type having the ability to memorize control data representing the current switch state of the switch, which control data includes a data bit input to turn-on / off circuits incorporated in the control circuit. The sensor array and the switching matrix may be built in different strata of a co-integrated structure or they may be built on separate wafers that are electrically connected. If the sensors are arranged on a hexagonal grid, the unit switch cells may be arranged on either a hexagonal or rectangular grid.

The aim of this invention focuses on the development of a high-efficiency bidirectional converter for power sources with great voltage diversity. In traditional bidirectional converters, the circuit topology with transformer form is the common usual. Moreover, the soft-switching techniques including zero-voltage-switching (ZVS) or zero-current-switching (ZCS) are usually used for alleviating the corresponding switching losses. However, there are four and upward power semiconductor switches in these circuit schemes. By this way, it will result in the increase of production cost, and the degeneration of conversion efficiency. The coupled-inductor bidirectional scheme in the proposed converter only adopts three power semiconductor switches to accomplish the objective of bidirectional current control. Under the situation of non-isolation circuit topology, it still possesses the protection of electric safety for operators. Due to the characteristics of high step-up and step-down ratio, the battery module with low voltage could be injected into a high-voltage dc bus for the later utilization, e.g., high-voltage load, front-end of inverter. Since the techniques of voltage clamping, synchronous rectification and soft switching are manipulated in this circuit topology, and the corresponding device specifications are adequately performed, it can achieve the goal of high-efficiency bidirectional power conversion for power sources with great voltage diversity.

One embodiment of the present invention includes multi-state current-switching magnetic memory element including a stack of two or more magnetic tunneling junctions (MTJs), each MTJ having a free layer and being separated from other MTJs in the stack by a seeding layer formed upon an isolation layer, the stack for storing more than one bit of information, wherein different levels of current applied to the memory element causes switching to different states.

A dynamic layer diagnostic device for smart power grid fault comprises a data collection and monitoring unit, a data processing unit, a data base unit, a communication unit and a man-machine interaction unit. A dynamic layer diagnostic method includes: when a smart power grid breaks down, calculating fault diagnosis starting conditions to conform a diagnosis strategy, wherein the fault diagnosis strategy comprises switch layer diagnosis, feeder layer diagnosis and transformer substation layer diagnosis; starting the switch layer diagnosis when changes of switch motion information are remarkable before and after the fault; starting the transformer substation diagnosis when changes of electricity amount information are remarkable before and after the fault; stopping the diagnosis when a fault element is the only one element during the diagnosis of the switch layer; otherwise, retrieving the switch historical action recording, and starting the transformer substation diagnosis when recording matched with the current switch action exists; and otherwise, starting the feeder layer diagnosis. The dynamic layer diagnostic method performs layering analysis on the fault, fully utilizes various fault information and improves fault diagnosis accuracy according to different characteristics of multisource information after the power grid fault and difficulty layer in obtaining and processing of various information.

The invention discloses a zero current switch active equalization circuit of power batteries and an implementation method. Zero current switch equalization is performed on the two batteries with maximum voltage differences in a battery pack by utilizing an LC quasi-resonant circuit. The equalization circuit comprises an MCU (Microcontroller Unit), an equalization switching circuit and the LC quasi-resonant circuit. The equalization switching circuit is used for switching the LC quasi-resonant circuit between the batteries under the control of the MCU; the MCU obtains voltages of every power battery with the aid of a voltage acquisition circuit so as to determine a highest battery voltage and a lowest battery voltage and numbers of corresponding batteries, and if a maximum battery voltage difference value is larger than a battery equalization threshold value, the equalization circuit is started; in an equalization state, the MCU controls the equalization switching circuit to cyclically switch the LC quasi-resonant circuit between batteries of the highest voltage and the lowest voltage; and when a switching frequency emitted by the MCU is equal to a natural resonant frequency of an LC, the zero current switch equalization is achieved.

A protector that protects a rectifier, and a wireless power receiver including the protector are provided. In one embodiment, a protector for an electronic device may include: a switch configured to control current flow to a rectifier of the electronic device; and a switch controller configured to: compare, with a predetermined threshold value, a voltage difference between an output voltage of the rectifier and a voltage of the electronic device; and transmit a control signal to the switch (i) to discontinue current flow to the rectifier when the voltage difference is greater than the predetermined threshold value, and (ii) to enable current flow to rectifier when the voltage difference is less than or equal to the predetermined threshold value.

The invention discloses a high-speed high-accuracy digital-to-analog conversion circuit. The circuit comprises a reference voltage generation circuit, a reference voltage-to-reference current conversion circuit, a coding circuit, a current source matrix and a switch array, wherein the coding circuit has a two-stage water-flowing type coding structure, a switch driving circuit array is connected between the two-stage water-flowing type coding circuit and the switch array, and a two-stage clock delay circuit is connected between a clock input signal and the two-stage coding circuit and provides a clock signal to the two-stage water-flowing type coding circuit; and the current source matrix, a current switch and the coding circuit have a '5+4+5' segmental structure, namely high 5 bits and middle 4 bits have a thermometer code structure, and low 5 bits have a binary code structure. The high-speed high-accuracy digital-to-analog conversion circuit effectively reduces the area and the power consumption of chips, reduces the complexity of the coding circuit, increases conversion rate, reduces burrs, and improves the dynamic characteristics of a digital-to-analog converter. The high-speed high-accuracy digital-to-analog conversion circuit is used for digital processing systems, audio / video conversion systems and communication systems.

A current switch is automatically calibrated when a flow of electric current is initiated in a power cable.

The present invention relates to a single-stage zero-current switching driving circuit for ultrasonic motor, which comprises: a buck-boost converter and a zero-current switching resonant inverter. The driving circuit according to the present invention integrates the buck-boost converter and the resonant inverter into a single-stage structure, so that the buck-boost converter and the resonant inverter share an active switch and a trigger signal, and therefore, the circuit is simplified and the loss caused by stage switching is reduced. Moreover, the buck-boost converter operates in a discontinuous-conduction mode (DCM), which allows the circuit to have high power factor, and enables the active switch to be capable of zero-current switching (ZCS), so that the loss caused by switching is largely reduced. In the driving circuit according to the present invention, there's no interaction of power between the buck-boost converter and the resonant inverter, so that the two circuits can be analyzed individually. Therefore, the driving circuit according to the present invention having simplified circuit, low loss caused by switching, and low manufacturing cost, can be a competitive product after being commercialized.

A DC power converter consisting of a series-resonant branch used to transform a DC voltage source into a DC current source exhibiting, a uni-polar, zero-current-switching characteristic. Frequency of the series-resonant branch, acting in concert with reflected load parameters, provides a forced oscillation frequency, Fo, component to an AC voltage source generated across the input winding of a power transformer by the resonant capacitor. Complex load parameters allow AC input current, displaced by 90° from the AC voltage source, to flow in the transformer primary winding throughout a composite, carrier-frequency cycle. Another component of the carrier-frequency consists of a resonant, natural oscillation frequency, Fn, resulting from resonance by the AC voltage source capacitance with the open-circuit inductance of the primary winding on the input power transformer. The composite carrier-frequency, Fo+Fn, transported through the input power transformer is directed to a rectifier / filter assembly and applied as a DC voltage to an output load. Thus, the uni-polar DC series-resonant branch is converted into an AC power transfer function, fully isolated from the input power switch, by the AC voltage source capacitor. The power transfer function characterizing a bi-polar power inverter requires a single power switch referenced to the input power return bus.

A multi-attribute handover judging method for a heterogeneous vehicle communication network comprises the following steps: a handover management entity reads information on a candidate network in a field network report buffer entity, and the diameter of the coverage region of the candidate network is calculated; a mobility prediction information management entity acquires position information and speed information of a mobile user, and sends the position information and the speed information to the handover management entity; possible residence time and throughput capacity in each neighbor access network of the mobile user is estimated, when the throughput capacity during handover is higher than the throughput capacity in a normal state, the candidate network is added in an alternative list; an optimal target access network is determined to be switched into the network by the handover management entity via an analytic hierarchy process and according to service quality requirements; when the intensity of the current switch-in network signal is lowered to a threshold value, a handover execution instruction is sent to carry out handover. The multi-attribute handover judging method provided by the invention avoids unnecessary handover when a traveling vehicle passes through a region covered by heterogeneous access network, reduces handover delay and ensures the continuity of the communication.

A methods and apparatus for remote management of switching network nodes in a stack via in-band messaging are presented. Switching nodes in the stack default to reserved switching node identifiers and stacking ports default to a blocking state upon startup, restart, and reset. Each command frame received via a blocking state is forwarded to a command engine at each switching node and is acknowledged with the current switching node identifier. Each acknowledgement frame bearing the reserved network node identifier triggers configuration of the acknowledging switching node. Switching nodes and the management processor track interrupt state vectors regarding events. An interrupt acknowledgement process is employed to track raised interrupts. Configuration of switching node is performed via command frames transmitted by the management processor and destined to a command engine associated with the switching node. Services provided by the management processor are requested via control frames destined to the switching node to which the management processor is attached and destined to the management port thereof. The advantages are derived from engineered switching node deployments wherein an appropriate number of management processors, less than the number of switching nodes in the stack, are employed to provide services to corresponding switching nodes in the stack, based on processing, control, and configuration bandwidth requirements. The in-band configuration and control of the switching nodes in the stack reduce deployment, configuration, management, and maintenance overheads.

The invention discloses an ultrahigh pressure cross linked polyethylene insulated flexible direct-current optical fiber composite submarine cable and relates to a direct-current cable. The ultrahigh pressure cross linked polyethylene insulated flexible direct-current optical fiber composite submarine cable is particularly used in large-power remote submarine power transmission in a flexible direct-current power consumption system of the vacuum control switch (VCS) current-switching technology and grid-tied connection among new energy alternating current systems of aperiodic operating wind power generation, tidal power generation and the like. The ultrahigh pressure cross linked polyethylene insulated flexible direct-current optical fiber composite submarine cable comprises direct-current cables, an optical fiber unit, a grounding feeder, filling strips, a main armor layer and an outer protective layer, wherein the two direct-current cables are respectively arranged on the left side and the right side, the optical fiber unit is arranged above the middle of the two direct-current cables, the grounding feeder is arranged under the middle portion of the two direct-current cables, and the cable is formed in a flat-supporting non-stranding mode; cable forming gaps are filled through arc-shaped filling strips; the direct-current cables, the optical fiber unit and the grounding feeder form the cable and then are armored through the main armor layer, the outer protectively layer is arranged on the surface of the main armor layer, anti-corrosion insulating glue is coated on each layer of polypropylene rope, and high-strength self-adhesive tapes are twisted outside the anti-corrosion insulating glue.

The present invention discloses a current-steering digital-to-analog converter and unit cells. The present invention proposes an n-well bias control circuit for generating a bias voltage whose magnitude is less than the power voltage, therefore the body effect of the transistors could be reduced. Relatively, the threshold voltage and VGS would be reduced. Therefore, even in a low-voltage operation, each transistor could be operated normally in the saturation region. Besides, the plurality of pairs of current switches could be implemented in the same n-well region, instead of being implemented in different n-well regions with leaving a space among each other. Finally, the chip area would be reduced.

A wireless communications mobile station (10) includes at least one antenna (240) and a RF transceiver (210,220) containing a direct conversion receiver (1) coupled to the antenna. The direct conversion receiver contains a low noise amplifier (3) for amplifying a received RF signal and for outputting the amplified RF signal to a current switching down-conversion mixer (4). The down-conversion mixer has a first input node for receiving the amplified RF signal, a second input node for receiving a local oscillator (LO) signal for mixing with the amplified RF signal and an output node coupled to an input of an operational amplifier forming a low pass filter (5A). In accordance with an aspect of this invention the low pass filter has a low pass pole generated by a resistor R and a capacitor C coupled in parallel in a feedback path of the operational amplifier, where a low pass comer frequency of the low pass filter is inversely proportional to the product of R and C. In a preferred embodiment at least the down-conversion mixer and the low pass filter are implemented as part of an integrated circuit, and the resistor and the capacitor are fabricated within the integrated circuit.

A soft-switched boost converter includes an active snubber to provide soft switching of all semiconductor components. Specifically, the current (“turn-off current”) in the rectifier is switched off at a controlled rate, the main switch is closed under zero-voltage switching (ZVS) condition, and the auxiliary switch in the active snubber is opened under zero-current switching (ZCS) condition. As a result, switching losses are reduced with beneficial effects on conversion efficiency and EMC performance.

The present invention discloses a power-on circuit of a peripheral component, which comprises a switch control circuit for controlling the enabling time of a P-type or N-type transistor. For a P-type transistor, the switch control circuit includes a pull-high element, a current source and a current switch. For a N-type transistor, the switch control circuit includes a pull-down element, a current source and a current switch. The enabling time of the P-type or N-type transistors are controlled by the switch control circuit and the capacitor shunt with the switch control circuit so as to slowly enable the transistor switch. In other words, the present invention uses the slowly increasing or decreasing characteristic caused by charging the capacitor with the current source to control the P-type or N-type transistor switch so as to obtain the purpose of slowly enabling the power supply. For designing an IC, it is easy to design a constant current source, which occupies only little area, and the disadvantage of the prior art is thereby resolved.

A soft-switching circuit for a power supply comprises a bridgeless rectifier circuit and an auxiliary circuit. The auxiliary circuit is connected to the bridgeless rectifier circuit, which comprises at least one filtering inductor, two main switches, two diodes and a capacitor. The filtering inductor is connected to the first diode. The first diode is connected to the second diode. The second diode is connected to the first main switch. The first main switch is connected to the second main switch. The diodes and the main switches are connected in parallel with the capacitor to reduce conducting loss. The auxiliary circuit comprises at least one resonant inductor, an auxiliary switch, at least two diodes and a voltage source circuit. The diodes are connected to the resonant inductor and further connected to the voltage source circuit. The voltage source circuit is connected to the auxiliary switch, whereby the soft-switching circuit can accomplish zero voltage switching and zero current switching to provide low conducting loss and low switching loss.