75 results about "Variable-voltage power supply" patented technology

There is disclosed a power supply stage (202), comprising: generating means for generating a power supply voltage from a high efficiency variable voltage supply (204) in dependence on a reference signal; adjusting means for receiving the generated power supply voltage (220), and adapted to provide an adjusted selected power supply voltage tracking the reference signal (216) in dependence thereon.

A powder spray coating discharge assembly (230, 260, 216, 228, 232) for connection to an electrostatic spray coating gun (210), the gun (210) having a gun body (212), means for connecting to a supply of coating powder and means for supplying a voltage (20) at first and second potentials respectively to first (292) and second electrical connections (294) each for connection to a respective one of a discharge electrode (232) and a counter electrode (260), the means for supplying the voltage (20) comprising: a variable voltage power supply (114) having an input connected to an electrical power source (110), an output connected to each of the first and second electrical connections (292, 294), a control circuit (128) for controlling the variable voltage power supply (20) and means (120) for sensing an output load, wherein the control circuit (128) is adapted to adjust the variable voltage power supply (20) to reduce the voltage and current in proportion to a sensed increase in load, or vice-versa.

A digital amplifier causes a gate drive circuit to drive output transistors, and switches a power source voltage supplied from a variable voltage power source, thereby amplifying an amplitude of a 1-bit digital signal outputted from a ΔΣ block. A variable voltage power source varies a driving voltage, by which an upper gate drive circuit drives output transistors, as a voltage obtained by adding (i) a constant voltage supplied to a lower gate drive circuit to (ii) a power source voltage, so as to correspond to the power source voltage. Thus, the driving voltage is minimized without influencing a switching operation of the output transistors. As a result, it is possible to reduce power consumption of the upper gate drive circuit in turning down the volume.

In at least one embodiment, an electronic system includes an amplifier having an on-chip charge pump to provide a gate boost voltage to boost a gate voltage of at least one on-chip field effect transistor (FET) of an output stage of an amplifier. In at least one embodiment, the gate boost voltage boosts the gate voltage higher than the supply voltage rail to increase an overdrive voltage of the on-chip FET. In at least one embodiment, the gate boost voltage boosts the DC bias of an input signal and, thus, generation of gate boost voltage by the on-chip charge pump is signal-independent, i.e. independent of the input signal. Increasing the overdrive voltage increases the efficiency of the amplifier by decreasing the difference between the maximum swing of the output voltage and the voltage supply rails of the at least one on-chip FET relative to conventional designs.

A dynamic voltage scaling system for a packet-based data communication transceiver includes a constant voltage supply, a variable voltage supply, and a voltage control unit. The constant voltage supply is configured to supply a constant voltage to at least one parameter-independent function of the transceiver, and the variable voltage supply is configured to supply a variable voltage in accordance with a control signal to at least one parameter-dependent function of the transceiver. Parameter-independent transceiver functions perform operations independent of a predetermined parameter and parameter-dependent transceiver functions perform operations dependent on the predetermined parameter The voltage control unit is configured to generate the control signal based on information provided by at least one parameter-independent transceiver function about the predetermined parameter.

The invention discloses an electric curtain, wherein the mounting frame of the electric curtain is a box body; a transverse diaphragm plate is used to divide the box body into an upper part and a lower part; a vertical diaphragm plate is used to divide the upper part into a mounting chamber and a wiring chamber; the lower part of the box body is provided with a chute; the entire drive device is arranged in the sealed mounting chamber of the upper part of the box body, the drive device consists of a guide way, guiders, a gear motor and a variable voltage power supply; the guide way is driven by the gear motor to rotate and drive the two guiders to perform reverse movement or relative movement along the guide way; the bottom surface of each guider is provided with a permanent magnet; two pulleys are arranged in the chute of the lower part of the box body; a magnet is embedded in the top surface of each pulley; the magnet and the permanent magnet at the bottom of each guider are opposite and attract to each other; the guiders move left and right on the guide way and attract the pulleys to slide left and right in the chute; the guide way and the guiders are made from engineering plastic; and the threads on the guide way are multi-start trapezoidal threads. The electric curtain has low running noise, small volume and convenient mounting method; the curtain can move to an assigned position for opening or closing; and the electric curtain is safe to use.

A semiconductor oscillator circuit for an EEPROM high voltage charge pump utilizes a current generating means to charge a first and a second capacitor alternatively. The charging current produced by the current generating means is inversely proportional to the ambient temperature. The charging current is proportional to the supply voltage and consequently, the oscillator frequency output remains constant over a variable voltage supply. Such a constant frequency characteristic makes a low voltage operation possible, but slows down the oscillator frequency as temperature increases. The slowing of oscillator frequency limits the charge pump output voltage and enhances the lifespan of the EEPROM cells.

A method and system thereof for reducing the energy consumed when decoding an encoded and synchronized multimedia data stream, wherein the data stream is non-preemptable and subject to precedence constraints. In a client-server environment, the server delivers to the client the stream for decoding. The client has a processor operating on a discrete variable-voltage power supply. Prior to transmitting the stream to the client, the server produces an execution schedule according to the precedence constraints. The server also assigns a voltage setting for each task in the schedule, wherein each task decodes a frame in the stream without preemption. The server transmits the execution schedule and voltage settings to the client with the encoded data stream. The schedule and voltage settings reduce energy consumption by the client while satisfying multimedia timing constraints.

The disclosed tunable stable-frequency/voltage frequency/voltage-changing power comprises: a three-phase transformer rectification filter circuit, a reversing-switch signal generation/ amplification circuit, an auxiliary power circuit, an independent power circuit, a triode voltage-regulation circuit, a reversing-switch power circuit, a transformer load circuit, a load voltage sampling circuit, a load environmental change voltage sampling circuit, a sample signal amplification/control circuit, and a initiation-control signal generation circuit for power protection. This product has well performance.

Constant current power supply arrangements can charge a capacitor with a constant current and are suitable as power supplies for laser diodes. A power supply for a laser diode comprises: a variable voltage power supply, a load path for carrying a laser diode, a shunt path connected in parallel with the load path, a current draining element for switching the shunt path, the current draining element being associated via a first feedback element with the variable voltage power supply such that current drained by the current draining element provides first feedback control of a voltage level of the variable voltage power supply, and a voltage operated second feedback element associated with both the load path and the shunt path to provide second feedback control of the current draining element to drain current via the current draining element in response to current changes at the load. A circuit arrangement for charging a capacitance comprises a load capacitance to be charged, a serially connected inductive component contributing to a serial frequency dependent impedance, and a variable frequency source for supplying charging current at a variable frequency, the variable frequency source being controllable to reduce frequency during charging of the capacitor, thereby to reduce the frequency dependent impedance and maintain a constant level of charging current to the load capacitance.

Static random access memory (SRAM) performance is enhanced through the use of appropriate latch strength control. For example, latch strength in an SRAM cell is increased during data store operations to reduce power dissipation and improve reliability. Latch strength can also be increased to improve read speed, while latch strength can be reduced to improve write speed. In an SRAM cell including at least a negative differential resistance (NDR) device as a pull-up element, this type of latch control can be achieved through appropriate biasing of the NDR device(s). For example, drain-to-source bias can be increased or decreased to increase or decrease, respectively, latch strength. Similarly, gate-to-source bias can be increased or decreased to increase or decrease, respectively, latch strength.

Methods and systems for evaluating the condition of a water tank having a powered anode protection system. The water heater includes a storage tank to hold water, a powered anode, and a control circuit. The control circuit includes a variable voltage supply, a voltage sensor, and a current sensor. The control circuit is configured to compare a measured parameter to a threshold. In some constructions, the threshold is indicative of a condition of the storage tank at which the powered anode is no longer able to protect the storage tank from corrosion. In other constructions, the threshold is predicative of a potential failure of the storage tank caused by corrosion. In some constructions, the control circuit is configured to estimate a time remaining until the predicted failure of the storage tank.

The invention provides an intelligent reverse power control system and control method for a variable-frequency variable-voltage power supply. The control system comprises an output power calculation unit, a frequency regulating amount calculation unit, a voltage frequency calculation unit, a voltage phase calculation unit, a voltage amplitude value calculation unit and a power module control unit, wherein the output power calculation unit is used for calculating the output power; the frequency regulating amount calculation unit is used for calculating the frequency regulating amount; the voltage frequency calculation unit is used for calculating the three-phase voltage output frequency; the voltage phase calculation unit is used for obtaining the three-phase voltage output phase; the voltage amplitude value calculation unit is used for calculating the output voltage amplitude value; and the power module control unit is used for controlling each power module of the variable-frequency variable-voltage power supply. According to the intelligent reverse power control system and control method, the frequency, the phase and the amplitude value of the output voltage are controlled, so that the generation of reverse power when a shore power supply and a ship power distribution system are in electric switch can be avoided consequently.

A water heater having energized electrodes and a method of controlling the water heater. The water heater includes a tank for storing water, a heating element, electrodes and a control circuit. The control circuit includes a variable voltage power supply, a voltage sensor and a current sensor. the control circuit is configured to controllably apply a voltage to the electrode, using the voltage sensor to determine the potential of the electrode relative to the tank when the voltage is not energizing the electrode, determine the current to be applied to the tank after the voltage is energizing the electrode, The conductivity state of the water in the tank is determined based on the electrode potential and the current, and the voltage applied to the energized electrodes is defined based on the conductivity state. The control circuit of the water heater can also determine whether the water heater is in a dry state.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor (103) generates a mechanical force that drives a component. A ripple count circuit (104) is configured to filter the drive current based on a rotational speed (ω) of the rotor (103) to generate a filtered drive current signal, and to generate a varying threshold based on the filtered drive current signal. Based on a comparison between the filtered drive current signal and the varying threshold, the ripple count circuit (104) generates a pulsed output signal indicative of the rotational speed (ω) of the rotor and a rotational position (θ) of the rotor.

The invention relates to a multimode starting system of a fuel cell power supply, comprising a controller connected by a line, a starting storage battery, a charger, an electrifying switch K1, a two-way relay K2, a variable voltage power supply, a diode D1, an external starting high voltage interface, an external starting low voltage interface and an external charging interface. By applying the system, multimode charging on the starting storage battery in the fuel cell power supply can be realized, and another storage battery starting system can be externally connected under the condition that the electric quantity of the starting storage battery is not enough to start the fuel cell power system. The system in the invention has the characteristics of low implementation cost, simple structure, and high safety and reliability, and is easy to operate.