101results about "Electric variable regulation" patented technology

An LED lighting device of AC power-driven type having a comparatively simple constitution and a high power efficiency. The device compares a signal voltage (rectified voltage) obtained by rectifying an AC source with a predetermined reference voltage and controls ON/OFF of a driving current to each LED of an LED array in response to a comparison result. In this constitution, a large voltage of AC source enables lighting of more number of LEDs, while a small voltage thereof enables lighting of less number of LEDs, thus enhancing power efficiency of the LED lighting device.

A lighting device comprising first, second and third groups of solid state light emitters, the first group emitting light having a dominant wavelength of 430 to 490 nm, the second group at 525 to 575 (in some devices 540 to 575 nm), the third group at 610 to 640 nm. In some devices, wavelength of light from emitters in first and second groups, and light from second and third groups, differs by at least 70 nm. Some devices emit light having CRI Ra of at least 70 when first, second and third groups of emitters are illuminated. Also, a lighting arrangement comprising first, second and third groups as above, in addition to a fourth emitter emitting light of dominant wavelength outside the ranges for the first, second and third groups, and not more than 10 nm different from a dominant wavelength of a color on an item to be illuminated.

The invention provides a control method of a flyback converter. The control method is a control method in a mixed control mode; in other words, the flyback converter works in a non-complementation state under light loads, the clamp switch pipe on time is shortened through down conversion, and light load losses are effectively reduced through down conversion; flyback converter works in a fixed-frequency drive complementation state under heavy loads, and the clamp switch pipe on time is prolonged. Compared with the prior art, the control method has the advantages that the voltage stress of a main switch pipe and a clamp capacitor can be effectively reduced, the main switch pipe off losses can be reduced, the clamp circuit current change slope is decreased, the EMI interference is reduced, the secondary current change slope is decreased, and the longer detection reaction time is provided for synchronous rectification. Meanwhile, the working area of a magnetic core in the third quadrant is enlarged, the maximum flux density is reduced, and the size of the magnetic core is reduced.

A switching power supply apparatus includes a PFM control circuit that outputs a clock signal Set such that a switching frequency of a switching element varies in accordance with a load state. The clock signal Set determines a turn-on timing of the switching element. A reference value of a current flowing through the switching element determines a turn-off timing of the switching element. A modulation signal is applied to the turn-off timing of the switching element to modulate one of a peak value of a drain current flowing through the switching element and an on-time of the switching element. Input control is performed separately on the clock signal Set and the modulation signal. Accordingly, even when the clock signal Set and the modulation signal contribute to each other to offset each other, modulation effects are not cancelled.

The following problem associated with a semiconductor device of silicon or the like having low band gap is solved by temperature estimation using voltage drop in such a semiconductor device having low accuracy and this complicates a circuit for temperature detection suitable for practical use or a configuration for implementing a detection system. A power converter provided with an inverter circuit includes a semiconductor device whose band gap is larger than that of silicon and which has a range in which the temperature coefficient of voltage drop during conduction is positive. The power converter further includes a measurement condition setting circuit. This circuit adjusts the timing of the following measurement values used for temperature estimation at a device temperature estimation circuit to each other so that a measurement value of a voltage measurement circuit and a measurement value of a current measurement circuit become data obtained by measurement at the same time.

A closing phase that produces the smallest energization flux error at a connection input point is calculated based upon a residual flux of the first closing phase and the preliminarily given pre-arc characteristic and closing time deviation characteristic of a three-phase circuit breaker, so that the calculated phase value is set as a target closing phase of the first closing phase. A closing phase that produces the smallest energization flux error when a residual flux of zero is calculated, so that the calculated phase value is set as a target closing phase of the remaining two phases. The total time required from the reference point to the target closing phases of the remaining two phases and a delay time corresponding to an integer multiple of a given cycle of the three-phase power supply is set as a target closing time of the remaining two phases.

The invention discloses a PWM/PDM double-mode modulation selecting circuit and a double-mode modulation method, which mainly solves the problem that the prior DC/DC converter is not high in average conversion efficiency within a heavy-load range. The whole circuit comprises a bias circuit, a band gap reference voltage source, an error amplifier, an isolation common-source follower, an oscillator, an integrator, a mode judgment comparator, a control comparator, a latch and a driving buffer, wherein the mode judgment comparator and the latch are connected between the output end of the error amplifier and the control end of the oscillator; the magnitude comparison of load current is converted into voltage comparison through the relation of duty cycle and triangular wave; and when the load current is larger, the circuit selects a PWM modulation mode otherwise the circuit selects a PDM modulation mode when the load current is smaller. Under the condition of guaranteeing the performance of the DC/DC converter, the invention improves the average conversion efficiency in a load change interval, and is applicable to the DC/DC switch converter with great load current change, low requirement on circuit volume and high requirement on conversion efficiency.

Asynchronous rectifier controller is provided on a secondary side of an insulation-type synchronous DC/DC converter and controls the synchronous rectifier transistor. A driver circuit controls the synchronous rectifier transistor. A photo coupler connection terminal is coupled to an input side of the photo coupler. An error amplifier amplifies an error between a voltage detection signal according to an output voltage of the DC/DC converter and its target voltage, and to draw a current according to the error from an input side of the photo coupler via the photo coupler connection terminal.

Measurement circuit components are included in an integrated circuit fabricated on a semiconductor substrate. These measurement circuits are connected to a voltage regulation circuit that provides the integrated circuit voltage source. These measurement circuits provide signals to control the voltage regulation circuit to adjust the voltage output to the integrated circuit based upon a measurement values obtained on the semiconductor device. These measurements include temperature and IR drop at locations on the semiconductor substrate, along with the frequency response of integrated circuit.

A dimming signal generation device outputs a square wave voltage signal having an on-duty corresponding to a dimming level to a dimming signal line from a time point when a predetermined time period has elapsed after power-up. In the dimming signal generation device, a specific voltage is outputted to the dimming signal line for the predetermined time period after the power-up.

A switching constant-current power device can stabilize current flowing to a load (e.g. a display device comprising an LED, or the like) even when the current is repeatedly interrupted. A voltage current detector is connected to the output side of a power converter and creates a voltage signal in accordance with the output voltage thereof; and a feedback circuit is provided between a controller for driving the power converter and a current detector, which generates a first feedback signal in accordance with the load current. The feedback circuit comprises a signal holding unit, which outputs a second feedback signal that was created by consulting the voltage signal at a given time, the feedback circuit supplying the first feedback signal, output by the current detector, to the controller when load current is flowing, and supplying the second feedback signal, output by the signal holding unit, to the controller when load current is not flowing.

The present invention includes error amplifier, current output sample circuit, current configuring circuit, and current limiting loop amplifier; wherein said current limiting loop amplifier output end connected with passage-way element input end to form current limiting loop, passage-way element locking current on maximum output enable current through loop action.

A reference voltage circuit includes first circuitry that generates a thermal voltage that is approximately proportional to absolute temperature, a first voltage multiplier, second circuitry that generates an inverse thermal voltage that is approximately inversely proportional to absolute temperature, a second voltage multiplier and a summer. The first voltage multiplier multiplies the thermal voltage to obtain a first multiplied voltage. The multiplied voltage is not equal to the thermal voltage. The second voltage multiplier multiplies the inverse thermal voltage to obtain a second multiplied voltage. The summer sums the first multiplied voltage with the second multiplied voltage to obtain a reference voltage.

A voltage generation circuit may include a static current circuit and/or a current mirror. The static current circuit may include a first resistor. The current mirror may include a second resistor, a third resistor, and/or an output terminal.

A multi-winding high step-up DC-DC converter includes a three-winding transformer to transform a low DC voltage to a high DC voltage; a power switch to control the energy flux of the primary winding of the three-winding transformer based on turning on/off the power switch; a first diode to control the current of the first secondary winding of the three-winding transformer; a second diode to control the current of the second secondary winding of the three-winding transformer; and a third diode to control the current of the primary winding. When the DC-DC converter is in the first operation state, the switch and the second diode are in on state, and the first and the third diodes are in off state. When the DC-DC converter is in the second operation state, the switch and the second diode are in off state, and the first and the third diodes are in on state.

The invention relates to the technical field of integrated circuits, in particular to a current mirror. The current mirror is characterized in that the current mirror is composed of a PMOS transistor MP1, a PMOS transistor MP2, an NMOS transistor MN1, a capacitor C1, a capacitor C2, a resistor R1, an input current source, an output end current source and a bias current source. The source electrode of the MP1 is connected with a power source VCC, the grid electrode of the MP1 is connected with the grid electrode of the MP2, and the drain electrode of the MP1 is connected with positive electrode of the input current source. The negative electrode of the input electrode source is grounded VSS. The drain electrode of the MN1 is connected with the power source VCC, the grid electrode of the MN1 is connected with the positive electrode of the input current source, the source electrode of the MN1 is connected with the positive electrode of the bias current source, and the substrate of the MN1 is connected with a connection point of the grid electrode of the MP1 and the grid electrode of the MP2 through the R1. A connection point of the source electrode of the MP1 and the drain electrode of the MN1 is connected with a connection point of the grid electrode of MN1 and the positive electrode of the input current source through the C1 and the C2 sequentially. The source electrode of the MP2 is connected with the power source VCC, and the drain electrode of the MP2 is connected with the positive electrode of an output current source. The current mirror has the advantages of being suitable for being used under low supply voltage, meanwhile improving the PSR of the current mirror, and being especially suitable for a current mirror circuit.

The invention discloses a current generating circuit with an adjustable temperature coefficient. The current generating circuit comprises a current mirror, an operational amplifier, a switching tube,at least two positive temperature coefficient resistors, at least two negative temperature coefficient resistors, a positive temperature coefficient switch and a negative temperature coefficient switch. Thus, on the basis of a voltage-to-current circuit in the prior art, output current is appropriately matched, the current generating circuit achieves the adjustable temperature coefficient, resistance matching is different from traditional pure serial connection or pure parallel connection, and circuit space is saved; the accuracy of the temperature coefficient is high.

The invention discloses an ultralow-power-consumption and high-performance bandgap reference source which comprises a reference current generation circuit, a first reference voltage generation circuit and a second reference voltage generation circuit, wherein the reference current generation circuit comprises a first PTAT (proportional to absolute temperature) circuit and first and second phase inverters arranged at the preceding stage of the first PTAT circuit; the first reference voltage generation circuit comprises a second PTAT circuit and a first operational amplifier circuit connected with the second PTAT circuit; the second PTAT circuit is used for generating a reference voltage; the first operational amplifier circuit is used for receiving reference level, a control signal and the reference voltage; the first operational amplifier circuit has a lager tail current when electrified and can quickly enter a normal working state; and the second reference voltage generation circuit comprises a third operational amplifier circuit, a voltage division circuit connected with an output of the third operational amplifier circuit, and a compensation circuit bridged between a first-stage output and a second-stage output. According to the bandgap reference source, the shortcoming of excessive dependence of most of bandgap reference source circuits on the threshold voltage of an MOS (metal oxide semiconductor) tube to a great extent is overcome, so that the structures of the circuits can normally work in the higher voltage input range.

Certain aspects of a method and system for a process sensor to compensate SoC parameters in the presence of IC process manufacturing variations are disclosed. Aspects of one method may include determining an amount of process variation associated with at least one transistor within a single integrated circuit. The determined amount of process variation may be compensated by utilizing a process dependent current, a bandgap current, and a current associated with a present temperature of the transistor. The process dependent current, the bandgap current and the current associated with the present temperature of the transistor may be combined to generate an output current. A voltage generated across a variable resistor may be determined based on the generated output current.

An electric charging system for a vessel, vehicle, or aircraft includes one or more energy storage modules on the vessel, vehicle, or aircraft; a pulse rectifier; a converter; and a voltage control transformer. The one or more energy storage modules are connected to outputs of the pulse rectifier. The voltage control transformer is connected to inputs of the pulse rectifier. The voltage control transformer includes a serial transformer having a plurality of pairs of transformer windings, connected together in series, one winding of each pair being adapted to be connected between the pulse rectifier and an input from an energy source and the other winding is connected to the converter.

A safe power supply circuit of the invention comprises a single-chip microcomputer control circuit, a loop protecting circuit and a voltage reducing and stabilizing power supply circuit which supplies electric power to the single-chip microcomputer control circuit. The output end of the loop protecting circuit is connected with a voltage detecting circuit. One end of the output end of the voltage detecting circuit is connected with the single-chip microcomputer control circuit, and the other end is connected with a loop switch protecting circuit. The output end of the loop switch protecting circuit is connected with a current detecting circuit. The output end of the current detecting circuit is connected with the single-chip microcomputer control circuit. The output end of the single-chip microcomputer control circuit is connected with a voltage detecting circuit. The safe power supply circuit can settle the problems of no protecting measures for overvoltage, overcurrent and reverse charging; and incapability of realizing automatic matching between a charger and an anode and a cathode of a battery. Higher safety and higher user-friendly performance of an electric vehicle are realized.

Systems and methods for dynamic AC line voltage regulation are provided. A simple and cost-effective method for achieving AC line voltage regulation in AC systems including split-phase systems, of which the voltage for each voltage line may be regulated over a specified range, is provided. Buck and boost regulation is achieved for lowering or increasing the line voltage, respectively, with reference to the incoming grid voltage. Systems for dynamic AC line voltage regulation may comprise an AC/AC converter which uses fractionally rated switches and magnetics that handle only a fraction of the load current, resulting in lower costs. The use of an AC snubber further provides safe and robust switching of the main switching devices by eliminating failure prone switching sequences that are dependent on accurate assessment of voltage and/or current polarity for AC or bi-directional switches.

The invention discloses a maximum power point tracking control method for a photovoltaic inverter. The method includes the steps: S1, allowing the voltage of a solar panel to be periodically disturbed in a fixed direction at a large step V_step_big from an open-circuit voltage point oc to a short-circuit point o, and recording power Ppv and operating voltage Vpv in each disturbance; S2, when MPPT (maximum power point tracking) minimum voltage V_min is disturbed, finishing the fixed-direction disturbance, finding out the maximum value Ppv_max of all the recorded power Ppv during disturbance from the point oc to the point V_min and the corresponding voltage value Vpv_max; S3, periodically disturbing at a small step V_step_small with the Vpv_max serving as an initial point to perform maximum power point tracking; and S4, as for the single-way MPPT, judging whether the operating voltage of the solar panel is smaller than the operating voltage of a bus or not in a scanning or searching state. The maximum power point tracking control method integrates MPPT tracking speed and tracking precision, two-way MPPT can be performed at the same time, and the method is applicable to mounting conditions of various solar panels.

A semiconductor device includes: a semiconductor chip including a nitride semiconductor layered structure including a carrier transit layer and a carrier supply layer; a first resin layer on the semiconductor chip, the first resin layer including a coupling agent; a second resin layer on the first resin layer, the second resin layer including a surfactant; and a sealing resin layer to seal the semiconductor chip with the first resin layer and the second resin layer.

A control device for a DC-DC converter includes a PWM controller for generating a PWM signal to a switch module of the DC-DC converter according to a feedback signal of the DC-DC converter, a logic circuit for generating a selection signal according to a magnitude of an output current of the DC-DC converter, and a multiplexer coupled to a plurality of voltages for selecting one of the plurality of voltages to be a supply voltage according to the selection signal.

The invention relates to a voltage reference circuit. Aiming at the problems that an existing reference circuit needs resistors and is high in technology requirement and large in power consumption, a low power consumption non-resistor full CMOS voltage reference circuit is provided. According to the technical scheme, the low power consumption non-resistor full CMOS voltage reference circuit comprises a bias current module, a positive temperature voltage module, a negative temperature voltage module and a voltage superposition module. Voltage superposition is used for outputting voltage reference, and the temperature coefficient of the voltage reference is reduced through selection of filed effect transistor structural parameters. According to the low power consumption non-resistor full CMOS voltage reference circuit, power consumption is low, the resistors are not needed, any type of bipolar transistors are not needed either, and the integrated circuit can be manufactured by the adoption of a standard CMOS technology, so that the application range and flexibility are obviously improved.