263results about How to "Reduce output current" patented technology

A display device includes a first layer having an optically active display portion, a second layer including a photovoltaic element, and a third layer including electronics operatively coupled to the first layer, wherein the electronics are configured to drive the optically active display portion. Further, the second layer is arranged between the first and third layers.

The invention relates to an LED street lamp applied to roadways, tunnels and other places where the requirement on illumination uniformity is higher. The LED street lamp comprises a light distribution system, a heat sink, a lamp body, a driving circuit and a light fixture installation adjusting mechanism; LED luminescence units are installed on one side of the light distribution system; the axial direction of each LED luminescence unit points at each zone of an object; the LED street lamp is also provided with an optimal optical system required by street illumination light distribution; power supply is controlled by the driving circuit in a shunt control way after the LED luminescence units are connected in series and in parallel; the heat sink is arranged on the other side of the light distribution system, thereby each LED luminescence unit can be ensured to be operated under normal temperature; and by installing the adjusting mechanism and a horizontal alignment device, the problem of ray offset as the position of the light fixture is not in place during the installation of the light fixture can be overcome.

The embodiment of the invention relates to a power-supply apparatus and control method, a power amplifying device. The device includes a includes linear branch and a first switch power supply group, the first switch power supply group includes a first current detector and at least two switch power supply branches, the switch power supply branch includes a hysteresis controller and a switch power supply drive and power circuit, the input end of the first electrical current detector is connected with the output end of the linear power supply branch, the input end of the hysteresis controller is connected with the output end of the first electrical current detector, the input end of the switch power supply drive and power circuit is connected with the output end of the hysteresis controller, the output end thereof is in parallel connection with the output end of the linear power supply branch. The embodiment of the invention can improve the band width and the tracking accuracy of the switch power supply, further improve the integral efficiency of the ET power amplifier.

A system and method for responding to a current overload condition in a power switch provides a class D topology that applies a current sink or current source to the gate of the power switch. The current sink or source decreases or increases current flowing through the power switch to regulate power switch output current in the event of an overload. A timer for current regulation can be provided to shut off the power switch if the overload condition persists. A set of differently rated switches can be used separately or together to provide a range of current regulation response, from a wide regulation range with a fast response, to a narrow regulation range with a slow response. The system provides a rapid response to an overload condition and output current regulation without disabling the power switch to overcome short term overloads.

The invention discloses a dimmable LED constant current source driver with wide voltage range, belonging to an LED light source driver in the illuminating field. The driver comprises a voltage identification circuit, a light compensation circuit, an MCU control circuit, a temperature compensation circuit and a dimmable constant current source circuit, wherein the output ends of the voltage identification circuit, the light compensation circuit and the temperature compensation circuit are all connected with the input end of the MCU control circuit, the PWM output end of the MCU control circuit is connected with the input end of the dimmable constant current source circuit, the voltage identification circuit and the dimmable constant current source circuit are both connected into direct-current or alternating-current input voltage, the light compensation circuit is connected with a photosensitive device, the temperature compensation circuit is connected with a thermistor, and the output end of the dimmable constant current source circuit is connected with an LED light source. The invention has low cost, small volume, stable and reliable working of a system and prolongs the service life of an LED.

The battery charging apparatus has a plurality of charging units connected in series. A charging unit has a series switch connected in series with a rechargeable battery, and a parallel switch connected in parallel with the series connected rechargeable battery and series switch. A charging control section controls charging of a rechargeable battery by switching the series switch and parallel switch ON and OFF. The charging control section changes the duty factor for switching series switches and parallel switches ON and OFF, switches a charging unit between a charging mode and a cut-off mode at a prescribed duty factor, and controls rechargeable battery charging currents to charge a plurality of batteries.

The invention discloses an LED drive circuit and a control method thereof. The LED drive circuit includes a main circuit and a control circuit, wherein the main circuit utilizes conduction and disconnection of a switch tube to realize conversion of direct current input voltage to direct current output current; the control circuit provides a driving signal to the switch tube to control conduction state of the switch tube; the control circuit acquires a current detection signal from the main circuit, and executes peak value current control according to the current detection signal and a peak value current reference signal so as to enable the switch tube to switch the conduction state in each switching period of the driving signal; the driving signal has a first duty ratio; the control circuit receives a light modulation signal, and controls output of the driving signal according to the light modulation signal; the light modulation signal has a second duty ratio; and the control circuit includes a peak value current compensation module, and compensates the peak value current reference signal according to the second duty ratio of the light modulation signal so as to restrain light modulation jitter.

The invention provides a high-voltage heavy-current compound injection DC circuit breaker synthetic test circuit and method. The DC circuit breaker is a hybrid high-voltage DC circuit breaker. The circuit comprises a heavy-current test circuit, a hybrid high-voltage DC circuit breaker and a high-voltage test circuit. The heavy-current test circuit and the high-voltage test circuit are both connected in parallel with the hybrid high-voltage DC circuit breaker. The DC circuit breaker synthetic test circuit and method not only can check the passing current capacity and breaking current capability of the hybrid high-voltage DC circuit breaker, but also can check the platform voltage withstand energy of the hybrid high-voltage DC circuit breaker. The high-voltage heavy-current compound injection DC circuit breaker synthetic test method reduces test implementation difficulty and cost.

The invention relates to a driving controller of an electric eddy current brake and a control method thereof, wherein the controller comprises a control unit, a driving circuit and an insulated gate bipolar transistor IGBT with large current and high pressure resistance electrically connected in sequence, and a rectification unit, a transformer T1 and a power input thereof connected with an IGBT output grid electrode in sequence. The control method comprises the steps that the control unit controls the pulse width thereof according to the input gear to modulate the duty ratio of the PWM output under the condition of normal circuit detection, or else turns off the output or restricts the duty ratio of the PWM output; the driving circuit receives the PWM output and drives the IGBT output according to the PWM output. The driving controller of the electric eddy current brake and the control method thereof has the high pressure resistance of 300V, and basically avoids the over-voltage failure used on cars, the controller can not be failed under various abnormal conditions combining a detection and protection circuit, thereby greatly enhancing the reliability, and solving the industrial problem of poor reliability of electronic control mode in the electric eddy current brake industry.

The invention discloses an accelerated life test circuit of a power electronic device. One end of a first switch (K1) is connected with a drain (D) of a device to be tested, and the other end of the first switch (K1) is connected with a gate (G) of the device to be tested; one end of a discharge resistor (R1) is connected with the gate (G) of the device to be tested, and the other end of the discharge resistor (R1) is connected with a source (S) of the device to be tested; a positive electrode of a constant current test power supply is connected with the drain (D) of the device to be tested, and a negative electrode of the constant current test power supply is connected with the source (S) of the device to be tested; two input ends of a failure judgment circuit are respectively connected with the positive and negative electrodes of the test power supply; one end of a second switch (K2) is connected with the drain (D) of the device to be tested, and the other end of the second switch (K2) is connected with the positive electrode of a constant current heating power supply; and the negative electrode of the constant current heating power supply is connected with the source (S) of the device to be tested.

The invention relates to a self-feedback linear galvanostat integrating an adjustable thermistor, which belomngs to the technical field of a semiconductor power device. The self-feedback linear galvanostat comprises a junction-type field effect transistor (JFET) and an adjustable thermistor, which are integrated together, wherein one end of the adjustable thermistor is connected with a JFET source electrode, and the other end is connected with a grid electrode of the JFET. The self-feedback linear galvanostat is centralized on the adjustable thermistor, and the adjustable thermistor can obtain a resistance value meeting the requirement of the output current through a laser cutting way, so that different types of products can be obtained in the same batch. The thermistor is a positive temperature coefficient, under the working situation, the temperature is increased, the resistance is increased, the output current is reduced, and the reliability of an application system is protected. The self-feedback linear galvanostat has advantages of high integration, stability in output current, adjustability of the current and good temperature property and can be applied to the fields such as light emitting diode (LED).

The invention relates to a method for improving the nonuniformity of brightness of an OLED (organic light-emitting diode) display panel. The method comprising the steps of processing collected image data to be displayed in RGB (red green blue) 565 form and separating the levels values of red, green and black of each row of pixel points; obtaining an average value of the levels of the three colors of all the pixel points of each row, and taking the average value as a reference value of current consumed by the three colors of the entire row; comparing the reference value with the levels value of the three colors of each pixel point in the row, and if deviation exists, adding or subtracting a weighting coefficient of the corresponding levels until the comparison with all the points is completed; obtaining corrected image data based on the weighting values; outputting the corrected image data to a driving circuit; and outputting the image data. By adopting the method disclosed by the utility model, the three primary colors of all the points of the displayed image can be treated, and the levels values of red, green and black can be regulated to strengthen the output current of low-brightness pixel points or to weaken the output current of high-brightness pixel points, thereby making up the problem that the brightness of pixel points of an OLED liquid crystal screen is nonuniform due to the crossed interference of current with partial pressure.

The invention discloses a power supplying system with multiple large-power high-voltage diesel generating sets in parallel operation. The system includes the high-voltage diesel generating sets, a high-voltage parallel operation system, a comprehensive protection device, a non-electricity protection device, a PT cabinet and a grounding resistor cabinet. The device has an independent-power-station design and under a condition without power grid voltage, the operation states of the generating sets can be adjusted according to external factors such as the operation condition of a main generator and electrical power parameters and the like and when in an emergency condition or when operation of the generating sets is needed, the parallel operation system is put into operation automatically so that grid connection use of any one or more generating sets in the system can be realized. An integrated console realizes concentrated monitoring and operation logic processing of the parallel system and automatic connection, automatic load sharing and automatic disconnection can be completed together and slope loading and slope unloading functions and control of automatic cooling stop are supported and system time and timer time can be set respectively according to the use condition and project demands and the whole parallel system is capable of automatically adjusting the number of sets which are put into operation according to the capacity of the load so as to meet stable power supply of the load.

The invention discloses a charging control device. The charging control device comprises a voltage monitoring unit, a control unit and an execution unit, wherein the voltage monitoring unit and the execution unit are connected to the output end of a charger and the control unit respectively; the control unit is used for controlling the execution unit to increase or decrease the output current of the charger; the voltage monitoring unit is used for judging whether the drop value of the output voltage of the charger is greater than a preset threshold value and sending judging results to the control unit; the control unit is used for controlling the execution unit to decrease the output current of the charger when the drop value of the output voltage of the charger is greater than the preset threshold value; when the drop value of the output voltage of the charger is less than or equal to the preset threshold value, the control unit controls the execution unit to increase the output current of the charger. The invention further discloses a charging control method and a POS terminal of the charging control device. According to the charging control device provided by the invention, the charging efficiency of the charger can be effectively improved.

A display device includes: a pixel array and a driving part for driving the pixel array, wherein the pixel array part includes first scanning lines and second scanning lines arranged in rows, and signal lines arranged in columns are provided on the first scanning line, the second scanning line The matrix pixels at the intersection of the two scanning lines and the signal lines provide power to each pixel's power line and ground line. The driving section includes a first scanner for sequentially line-scanning the pixel row by sequentially supplying the first control signal to each of the first scanning lines, sequentially supplying the second control signal to each of the second scanning lines together with the sequential line scanning A second scanner, and a signal selector that provides video signals to the signal line columns along with sequential line scanning.

The invention relates to a power source management system which comprises a power source device, a detection module and an output power control module, wherein the power source device comprises a battery and a power source input module; the detection module comprises a charging control chip; the charging control chip is electrically connected with the battery, the power source input module and the output power control module; the charging control chip controls the charging current of the battery and detects the output current of the power source device; and the power source device corresponding to the charging control chip is also respectively provided with an over-current protection point, and when the current output by the power source device is detected to exceed the corresponding over-current protection point, the charging control chip can be used for reducing the charging current of the battery or the output power control module can be used for reducing the working frequency of the portable electronic device so as to reduce the output current of the battery or the power source input module. The invention also provides a portable electronic device with the power source management system.

The invention discloses a temperature control circuit in a DC-DC (direct current) converter. The temperature control circuit comprises a thermistor for sensing the temperature change of the working environment; the thermistor is connected between a non-inverting input end of an operational amplifier and a power anode; reference voltage is set at an inverting input end of the optional amplifier; a capacitor is connected in series with a feedback resistor and then connected between the inverting input end and an output end of the operational amplifier; a first voltage dividing resistor is connected between the non-inverting input end of the operational amplifier and a grounding point; the output end of the operational amplifier is connected with the cathode of a diode through a current limiting resistor; and the anode of the diode outputs a control signal. The temperature control circuit disclosed by the invention has the advantages that: the enclosure temperature can be detected through the thermistor; when the enclosure temperature reaches a set value, the circuit starts working and controls PWM (pulse width modulation) to reduce the duty cycle and achieve the aim of fixing the enclosure temperature by reducing the output current; and thus the circuit can be used for a long time at high temperature.

A DC power supply redundancy system comprises an automatic switching component and a DC redundancy module. The automatic switching component comprises a first power input end, a second power input end and a power output end. The first power input end is connected with a power-grid power supply unit. The power output end is connected with one AC input end of an AC / DC converter. One DC output end of the DC redundancy module is connected with the second power input end of the automatic switching component. When power supply of the power-grid power supply unit is abnormal, the power output end of the automatic switching component is switched for connecting with the second power input end, thereby supplying a DC redundancy power to the AC / DC converter by the DC redundancy module, wherein the voltage of the DC redundancy power is higher than the lowest working voltage of the AC / DC converter.

The present invention discloses a magnetic force effect-based parallel composite beam piezoelectric-electromagnetic energy capture device. The magnetic force effect-based parallel composite beam piezoelectric-electromagnetic energy capture device comprises a shell, two sets of composite beams which are parallel to each other, two permanent magnets and two induction coils; the two induction coils are disposed on the opposite inner side walls of the shell; the two sets of composite beams are disposed between the two induction coils; each set of composite beams comprises a plurality of cantilever beams and a base connected with one end of each of the plurality of cantilever beams, the other ends of the cantilever beams being fixedly connected onto the inner side wall of the shell; the two permanent magnets are arranged on the bases of the two sets of composite beams respectively and directly face the two induction coils respectively; and the upper and lower surfaces of the cantilever beams are provided with piezoelectric sheets. The piezoelectric power generating device of the present invention can be more adaptive to random, broadband, low-frequency, large-amplitude and high-intensity vibration energy recovery in the environment.

The invention relates to the technical field of electrons, and provides a charging circuit. The charging circuit comprises a charging control circuit and at least two charging integrated circuits (ICs), wherein the at least two charging ICs are connected with each other in parallel; a common output end of the charging ICs is connected with a charging input end of a battery; and the charging control circuit is used for controlling the at least two charging ICs to charge the battery. The invention further provides a mobile terminal. According to the charging circuit and the mobile terminal provided by the invention, the cost can be effectively controlled when heavy current charging is achieved.

The invention relates to a temperature detector and a use method thereof. The temperature detector comprises a first current mirror, a second current mirror, a first pulse generator, a second pulse generator, a phase detector and a controller, wherein the current of the first current mirror varies with temperature, and the current of the second current mirror does not vary with the temperature. The output current of the second current mirror is increased by the controller when an output pulse of the first pulse generator occurs earlier than an output pulse of the second pulse generator or decreased when the output pulse of the first pulse generator occurs later than the output pulse of the second pulse generator.

The invention discloses a rear preregulator DC / DC converter which is mainly used for realizing preliminary adjustment of voltage waveform output by a power transformer and achieving a purpose of multiple output of large current. The rear preregulator DC / DC converter mainly comprises a surge inhibition circuit (1), filters (2) and (4), a main power loop (3), a main control circuit (5), a phase synchronous circuit (6) and a rear regulation and control circuit (7). The surge inhibition circuit (1) realizes limit on surge current when being started, the filters (2) and (4) realize filter of the circuit and reduce EMI (Electro-Magnetic Interference) of the converter, the main power loop (3) completes change and isolation of input and output voltages, the phase synchronous circuit (6) realizes a drive pulse that the rear regulation and control circuit (7) is synchronous with the main control circuit (5), and a rear regulation circuit (8) completes the regulation of the output voltage. All inductors and transformers in the converter are realized by adopting a multilayer PCB (Printed Circuit Board) transformer technology.

The invention discloses a transformerless hybrid active power amplifier and implementation and control methods thereof. The transformerless hybrid active power amplifier comprises a double-turned passive filter and a diode-clamped active filter. The diode-clamped active filter is a tri-level inverter. The double-turned passive filter comprises three passive filter branches connected with phases A, B and C of a power grid respectively. Each passive filter branch comprises an impregnated capacitor (C1), a divider capacitor (C2), a parallel capacitor (C3), a first inductor (L1) and a second inductor (L2). Impregnation points of the three passive filter branches are connected with three terminals on the alternating-current side of the tri-level inverter through three output inductors (L) respectively. The transformerless hybrid active power amplifier features both low cost of a PPF (passive power filter) and excellent filtering and dynamic performance of an APF (active power filter), is easy to implement and is effective in filtering.

A permanent magnet synchronous towing machine without gear wheel includes the stator, rotor and the brake equipment. The stator frame, the stator case and the shoring cover are cast as a whole. Arc type permanent magnets are affixed to the inner side of the rotor wall along the direction of circle. Shaft is mounted on the axle hole of the axle housing of the rotor. The iron cords are pressed to the outer side of the shorting cover along direction of the circle. The rotation coder is positioned on the back end of the shaft. The stretch type electromagnetic brake providing thrust in bi-directional is mounted between two brake arms on the base. The brake shoes with hinge jointed on the brake arms are fitted on the symmetrical two sides of the outer wall of the rotor. The towing wheel is fixed on the circular bead of the end part.

The invention discloses a constant-flow blower fan and a control method thereof. The control method of the constant-flow blower fan comprises the steps that S100, when the rotating speed of the constant-flow blower fan is n and the value of an output current of a variable-frequency driver is less than a set value, the output current of the variable-frequency driver is increased; when the value of the output current of the variable-frequency driver is greater than the set value, the output current of the variable-frequency driver is decreased. The working current and voltage of the blower fan are controlled by controlling the output current of the variable-frequency driver, and therefore the rotating speed of the blower fan is controlled; after the rotating speed of the blower fan is changed, the corresponding air quantity will be changed, and therefore the air quantity of the blower fan is kept in a reasonable range, and using performance of the blower fan is improved.

The invention discloses a direct-current combiner box, an inverter, a photovoltaic system and a protection method. The combiner box comprises a switching device, a sampling circuit and a controller, wherein the switching device is connected in parallel between the positive input end and the negative input end; the sampling circuit is used for collecting at least one of input parameters and outputparameters of the combiner box; and the controller is used for controlling the switching device to be switched on when determining that a short circuit occurs between the output positive cable and theoutput negative cable or the output positive cable and the output negative cable are reversely connected according to the at least one parameter, and the switching device, the positive input end andthe negative input end form a closed loop. When the output end of the combiner box or a post-stage circuit of the output end is short-circuited, most of short-circuit current passes through the closedswitching device to form backflow, so that the current generated by the input end of the combiner box is reduced to be output from the output end of the combiner box, and overcurrent burnout of an output cable of the combiner box caused by overlarge output current of the combiner box is avoided. According to the scheme, the combiner box can be protected when positive and negative output cables are reversely connected.

The present invention relates to a power supply circuit used in devices using various batteries such as mobile phones, and more particularly to a power supply circuit capable of reducing power consumption. When the CPU 11 is in normal operation, the DC-DC transformer 2 is used to efficiently step down the power supply voltage VDD to the voltage Va, and then the voltage regulator 3 is used to step down to obtain a stable voltage Vb, which is supplied to the CPU 11; if the CPU 11 is in a standby state, the DC - The DC transformer 2 becomes inactive, stops its operation, and suppresses power consumption. At the same time, only the voltage regulator 3 adjusts the power supply voltage VDD passed through the DC-DC transformer 2 to a desired voltage Vb, and supplies it to the CPU 11 . The power supply circuit of the present invention can reduce power consumption in a standby state, and at the same time, even when a device to be supplied with power is intermittently operated in the standby state, power can be supplied to the device.

A power-supply apparatus for outputting a voltage via one or more switching elements is disclosed. The apparatus includes a voltage-generating circuit for generating an output, voltage Vo proportional to a voltage between an input end and an output end of the switching element, and a control circuit for controlling an operation of the switching element depending on the output voltage Vo. The control circuit causes the switching element to reduce an output current when the output voltage Vo exceeds a predetermined voltage Vs.

A power supply for supplying power to a lamp with functions of dimming, over-current protection, over-voltage protection, arcing protection, and low-temperature start-up is provided. When frequency of the output current exceeds a predetermined value, the power supply is turned off to accomplish a dimming goal and extend lifetime of the lamp. When abnormal statuses such as open-circuited status, short-circuited status, or arcing status occur, a surge current induced by the abnormal statuses may be eliminated to prevent the power supply from being damaged. A high-frequency current detection circuit is configured to detect whether a current supplied to the high-voltage load is a high-frequency current to prevent damage to the electronic elements in the high-voltage load. A current adjusting circuit is configured to adjust an alternating current outputted to a lamp set in response to an environment temperature to supply an adequate alternating current at a low temperature for starting the lamp set.

The current limiting protection device comprises the output current detection circuit for obtaining the sampling signal of the output current of the voltage division power source, outputting the current detection signal in proportion to the said output current. The multistage current limit control circuit for adjusting the voltage ratio of the current sampling signal of the output current detection circuit. The output voltage detection circuit for outputting the voltage detection signal, which is proportion to the output voltage signal of the voltage division power source. The current limiting point reference circuit for providing the constant current reference signal or the signal being proportion to the voltage detection signal. The comparison circuit for outputting the current limit control signal. Based on the working condition, the invention changes the output current limiting point of the power source so as to realize output power protection.