Abstract: A cold cathode tube lighting device prevents emission-position-dependent unevenness from occurring in the brightness of light emitted from the cold cathode tube lighting device and includes a plurality of discharge tubes connected in parallel; ballast capacitors each integrally attached to a respective one of the plurality of discharge tubes; power supplies arranged to supply power to the plurality of discharge tubes; and a voltage detection unit connected to the plurality of discharge tubes to detect voltages between pairs of internal electrodes of the plurality of discharge tubes. The power supply to the plurality of discharge tubes is controlled according to the voltages detected by the voltage detection unit.

Abstract: A drive circuit drives LED groups each of which has a plurality of LEDs connected in series. The drive circuit includes nMOSFETs which drive the LED groups, current regulating circuits which determine drain currents of the nMOSFETs, and subtracters which control the current regulating circuits to keep the sum of the current values of adjacent two nMOSFETs constant. The LEDs can be switched on/off efficiently even when there are differences between forward voltages of the LEDs.

Abstract: A control signal is provided for turning on and turning off a lamp of a backlight source. For a first duration when the liquid crystal is rotating, adjust a frequency of the control signal to turn on and turn off the lamp of the backlight source consecutively or adjust a duty cycle of the control signal to turn off and then turn on the lamp of the backlight source. Thus, the backlight source has a luminance value for the first duration, and the control signal turns on the lamp of the backlight source for a second duration when the liquid crystal is in the steady state.

Abstract: A driving apparatus of a light emitting diode (LED) and a driving method thereof are provided. In the driving method, when the driving apparatus performs dimming and a duty cycle of a dimming signal is smaller than a predetermination value, outputting time of driving currents are equally allotted in a period, and a magnitude of each driving current is regulated correspondingly. When the driving apparatus performs dimming and the duty cycle of the dimming signal is equal to or greater than the predetermination value, the driving currents are simultaneously output in the period, and the magnitude of each driving current is regulated according to the dimming signal. Therefore, an audio noise and an electromagnetic interference caused by excessive variation of a sum of the driving currents are suppressed.

Abstract: A discharge lamp lighting device includes: a power control circuit outputting DC current; an AC conversion circuit being supplied with the DC current and generating and outputting discharge-lamp driving AC current by inverting the polarity of the DC current at a predetermined time; and a control unit performing a duty ratio control process of controlling a duty ratio on the basis of a polarity inversion time of the discharge-lamp driving AC current on the AC conversion circuit and performing an interval current control process of controlling a current value of the DC current every polarity inversion time interval on the power control circuit. Here, the control unit performs the interval current control process so as to control a difference between an average value and a maximum value of the DC current of each polarity inversion time interval on the basis of a difference between the duty ratio and a predetermined reference duty ratio.

Abstract: A light source driving device for driving a light emitting component is disclosed. The light source driving device includes a voltage converter coupled to the light emitting component for converting an input voltage into an output driving voltage according to a voltage control signal, a dimming unit coupled to the light emitting component for implementing a dimming process according to a dimming signal, a current source coupled to the dimming unit for providing a driving current to drive the light emitting component, and a control unit coupled to the dimming unit and the voltage converter for detecting a dimming state to generate a dimming detection signal and generating a reference voltage according to the dimming detection signal, wherein the control unit controls the voltage converter to generate the output driving voltage so as to driving the light emitting component.

Abstract: The present invention provides a method and apparatus for driving multiple parallel discharge lamps, which increases the switching frequency once the open lamp condition is detected to provide an output voltage that is high enough to ignite the lamp again.

Abstract: A device for supplying diodes LED includes an electric bridge (ABHG) with input terminals (A, B) and output terminals (H, G), including diodes (DS1, DS2) interposed between branches (AH, BH), with cathodes turned toward the terminal (H); Two MOSFET elements (M1, M2) are interposed between the branches (AG, BG). A capacitor (C) is derived between the terminals (H) and (G). A switch (KR) and LED diodes arranged in series, with their anodes oriented toward the terminal (H), and a first current sensor (S1) are arranged along a derived branch (R), between the terminals (H) and (G). An electric control unit (CE) receives in input feedback control signals coming from the first sensor (S1) and operates opening/closing of the switches (M1) and (M2), as well as of the branch switch (KR) in suitable relation with the trend of the alternating current (iz), to obtain a predetermined trend of the branch current (ir.) for power supplying the LED diodes.

Abstract: An LED driving circuit and a MOSFET switch module thereof is disclosed, and the MOSFET switch module which is used to control a current of the LED driving circuit. The present invention employs a voltage clamping device to clamp the voltage level of the drain of transistor in the MOSFET switch module when being turned off. Via this way, the requirement for the withstand voltage of the transistor is lowered, and so the cost and power consumption thereof is reduced.

Abstract: A light emitting array is described and includes first, second and third light emitting elements, and first and second current sources. The first light emitting element includes first and second terminals, and is characterized by a first operating voltage Vop1 at or above which it is substantially operable to emit light. The second light emitting device includes a first terminal, and a second terminal coupled to the second terminal of the first light emitting element, the second light emitting element characterized by a second operating voltage Vop2 at or above which the second light emitting element is substantially operable to emit light. The third light emitting element includes a first terminal coupled to the first terminal of the first light emitting element, and a second terminal, the third lighting emitting element characterized by a third operating voltage Vop3 at or above which it is substantially operable to emit light.

Abstract: A current-limiting protection circuit of remotely controlled ceiling fan-lamp is disclosed. The current-limiting protection circuit includes a microcontroller unit for detecting rectangular wave signal reflective of the power used by a lamp load. The rectangular wave signal is compared with nominal value. In the case that the positive bandwidth of the rectangular wave signal is larger than the nominal value, it is indicated that the lamp load is in an overloaded state. Under such circumstance, the microcontroller unit controls a lamp load driving unit to change driving manner and lower the power used by the lamp load to a value within the nominal range.

Abstract: According to one embodiment, there is provided an optocoupler system configured to generate current signals having high, low and no amplitude portions in response to the receipt of logic high and low input signals. The varying amplitude portions of the current signals are used to drive other portions of the isolation circuitry, and result in reduced power consumption and dissipation, as well as reduced pulse width distortion.

Abstract: A wind turbine is disclosed. The wind turbine includes comprising an inflatable portion comprising one or more blades and a device for rotatably driving the inflatable portion at a predetermined rate for a predetermined time.

Abstract: A load driving circuit is disclosed that allows a charge pump circuit to operate at an optimum step-up ratio without frequently changing the step-up ratio. The load driving circuit includes a step-up circuit; a current setting circuit that sets a value of an electric current to be supplied to a load; a constant current circuit generating a constant electric current having the set value; a determination circuit; and a control circuit. In response to a load current setting signal, the current setting circuit sets the electric current to be maximum, and decreases the electric current step by step down to a preset value. Each time the electric current is decreased by one step, the control circuit changes the step-up ratio according to the determination results of the determination circuit, until the constant current circuit supplies the set electric current.

Abstract: A discharge lamp lighting apparatus includes a switch circuit for DC/AC converting, a discharge lamp connected to a secondary winding of a transformer, a current detector detecting an AC output current of the discharge lamp, an error amplifier outputting an error signal to a detected current, a control circuit generating control signals that turn on/off the switching elements in such a way as to control the AC output current at a predetermined value, and a time division signal generator generating a time division signal at the start of an ON/OFF operation of the switching elements, wherein the time division signal delays a change in a burst dimming signal or has a predetermined inclination on the burst dimming signal. The error amplifier changes the error signal according to the time division signal from the time division signal generator.

Abstract: The system, which provides a control signal, includes an over-current control unit, a time clock that provides a periodic time signal, and a clock generator unit that includes a first input terminal, a second input terminal, and an output terminal. The first input terminal is coupled to the time clock and the output terminal is coupled to the over-current control unit. The first input terminal of the clock generator unit receives the periodic time signal and the second input terminal of the clock generator unit receives a modification signal. The clock generator unit generates a clock signal based on the periodic time signal and the modification signal. The output terminal of the clock generator unit provides the clock signal to the over-current control unit, and the over-current control unit provides a control signal based on the clock signal.

Abstract: An exemplary apparatus embodiment provides a plurality of operating modes for solid state lighting, such as a flash mode and a constant or background lighting mode for use with devices such as cameras. An exemplary apparatus comprises a memory adapted to store a plurality of average current parameters; and a controller adapted to modulate an energizing cycle time period (“T”) for providing power to the solid state lighting as proportional to the product of the selected average current parameter (“?”) and a reset time period (“TR”) for an inductor current to return to a substantially zero level from a predetermined peak level (T??·TR). The average current parameter is predetermined as substantially proportional to a ratio of a peak inductor current level (“IP”) to an average output D.C. current level (“IO”)(??IP/IO).

Abstract: A controller for optical transducers uses delta-sigma signal density modulation to reduce electromagnetic interference.

Abstract: Device for controlling the current through a PN junction includes a voltage source connected in series to, in order, firstly a controllable current generator having an input connected to the voltage source, an output and a control input, thereafter a measurement resistor connected to the output, and finally a controlled output to which the PN junction is connected. The device further includes a control signal input, a differential amplifier and an integrating device, which includes a balanced integrator. The current through the output of the controllable current generator is proportional to the voltage difference between its input and its control input, and the reference voltage of the integrating device is constituted of the voltage of the voltage source.

Abstract: A color-changing light array powered by a driver circuit, the driver circuit responsive to a controller circuit, and the controller circuit configured to change display lighting patterns or colors based on modes of operation and off-on power cycle intervals.

Abstract: A method for optimizing an LED lighting system cost includes steps of determining LED costs, power source costs, and total costs associated with a plurality of LED quantities, and identifying a lowest total cost as an optimal cost. A LED lighting system includes an LED operated by a constant-current driver at less than its maximum current capacity. A programmable controller including a feedback routine is used to compensate for intensity drift as an LED ages. Other embodiments of LED lighting systems include multiple LEDs producing light having various spectrums to optimize the lighting system efficiency and the effectiveness. A charge controller including an MPPT routine is advantageously employed with a LED lighting system powered by a limited-capacity power source.

Abstract: According to one embodiment, there is provided an optocoupler system configured to generate current signals having high, low and no amplitude portions in response to the receipt of logic high and low input signals. The varying amplitude portions of the current signals are used to drive other portions of the isolation circuitry, and result in reduced power consumption and dissipation, as well as reduced pulse width distortion.

Abstract: A lighting control device of a lighting device for a vehicle includes a switching regulator for supplying a driving current to a semiconductor light source. The lighting control device also includes control means having a current detecting portion for detecting the driving current and serving to control dimming of the semiconductor light source in order to reduce a mean current of the driving current by repeating driving and stopping operations of the switching regulator at a high speed upon receipt of a dimming control signal. The current detecting portion has a current holding portion for holding the driving current, detected for a driving period of the switching regulator, for a stopping period after a passage of the driving period.

Abstract: An LED-based lighting device and method for making the same are disclosed. The lighting device includes an LED light source mounted on a heat sink, a power adaptor, and a controller. The power adaptor is configured to be interchangeable with a conventional incandescent bulb power adapter. The controller provides an average current to the LED light source when power is coupled to the device via the power adaptor. The average current causes the LED light source to generate light of a predetermined standard intensity that is substantially independent of variations in the LED light source from device to device. In one aspect of the invention, the LED light source includes a plurality of LEDs connected in series, the LEDs are bonded to the heat sink and connected to one another in series by wire bonds and to conducting traces on the heat sink.

Abstract: A driver (10) for driving a gas discharge lamp (L) comprises a current generator (1; 2) for generating a lamp current with a main lamp current component and, for arc-straightening purposes, a ripple current component. A controller (3) controls the current generator such as to set the ripple frequency (fR) and ripple amplitude (M). A memory (5) contains data defining a set point (SP) for the ripple frequency and ripple amplitude. A measuring device (4) provides at least one measuring signal indicative of arc curvature and arc stability. The controller is capable of operating in a ripple optimization mode in which the controller makes small adjustments to the ripple frequency and ripple amplitude to find improved arc-straightening, and, if such improvement is found, controls the current generator on the basis of the adjusted set point or otherwise resumes operation on the basis of the original set point (SP) in the memory (5).

Abstract: A current-limiting protection circuit of remotely controlled ceiling fan-lamp is disclosed. The current-limiting protection circuit includes a microcontroller unit for detecting rectangular wave signal reflective of the power used by a lamp load. The rectangular wave signal is compared with nominal value. In the case that the positive bandwidth of the rectangular wave signal is larger than the nominal value, it is indicated that the lamp load is in an overloaded state. Under such circumstance, the microcontroller unit controls a lamp load driving unit to change driving manner and lower the power used by the lamp load to a value within the nominal range.

Abstract: A device capable of generating electricity includes a rotating unit and a piezoelectric component. The rotating unit is rotatable about a rotation axis and includes a plurality of strikers that are disposed at angularly spaced apart positions relative to the rotation axis and that define a plurality of voids, each of which is located between an adjacent pair of the strikers. The piezoelectric component has a portion that extends into one of the voids. Rotation of the rotating unit results in the strikers striking the portion of the piezoelectric component intermittently, and causes the piezoelectric component to deform, exhibit a direct piezoelectric effect and generate electricity.

Abstract: A light-emitting device driven by an inertial power includes an inertial module, a magnetic element, a magnetic-conductive element, at least one wire, and a light-emitting module. Under an inertial effect, the inertial module drives the magnetic element to rotate, such that a magnetic field generated by the magnetic-conductive element changes due to the rotation of the magnetic element. Moreover, the wire wound around the magnetic-conductive element generates a drive current in response to the changing of the magnetic field, so as to drive the light-emitting module to emit a light. As such, the magnetic field is changed under an inertial power, so as to generate a drive current for driving the light-emitting module, thereby achieving, a renewable energy source, environmental protection, and power-saving purposes.

Abstract: A drive circuit (1) for driving a load (3) comprises: a switched mode power supply (10) for supplying at the output (2a, 2b) a switched output current (IL); a controller (20) for controlling the power supply; a current sensor (15) for generating a current sense signal (Vi 5) representing the output current (IL); a voltage sensor (30) for generating a voltage sense signal (Sy) rep->resenting the output voltage (Vp; Vp+Vis) of the circuit. The controller receives the current sense signal, and generates a switching time control signal (Sc) for the switched mode power supply (10) on the basis of the current sense signal. The controller further receives the voltage sense signal. In response to a change in the voltage sense signal, the controller changes the switching time control signal such as to effectively compensate an effect of the output voltage change on the average value of the output current.

Abstract: Disclosed herein is a discharge lamp lighting device which realizes the minute control of the lighting sequence and electric power of a high-pressure discharge lamp and the control of various anti-error protecting functions by mounting a microcomputer. However, since microcomputer processing typically progresses in accordance with the programs previously recorded on a ROM, various actions of the discharge lamp are controlled in accordance with ROM-recorded data settings. To modify these settings, the contents of the ROM need to be updated. Therefore, a function for communicating with an external device is assigned to the microcomputer so that various data settings can be modified.

Abstract: An exemplary LED control circuit includes an observation circuit to detect brightness of ambient light and generating a voltage signal accordingly; a sampling circuit to receive the voltage signal and generate a control signal according to the voltage signal; a controller to generate a selection signal according to the control signal received from the sampling circuit; and a regulating circuit connected to an LED driving circuit for adjusting a current of the LED driving circuit according to the selection signal.

Abstract: A system and method for color changing lighting comprising a pre-programmed controller along with driver circuit, a single or combination of LEDs and an OFF/ON switch which is used for making selection of mode of operation as well as switching the system ON/OFF. Brightness is changed using pulse width modulation. The LED's are selectively activated by programmed variable pulse to generate desired color mixing effect. The resulting illumination may be controlled by a computer/micro-controller program to provide pre-designed complex patterns of light in virtually any environment.

Abstract: A driver device for driving light emitting elements comprises a data latch having an input coupled to an input signal, a current control circuit having an input coupled to the data latch, and an output coupled to the input of an output stage, the latter being configured to drive the light emitting elements. The driver device has a power control circuit having an input coupled to the output of the data latch and an output coupled to the input of the current control circuit. The power control circuit is configured to control the current control circuit and the latter is configured to deliver a first current when the data inputted to the power control circuit is in a first state and a second current when at least part of the data inputted to the power control circuit is in a second state.

Abstract: A controller for optical transducers uses delta-sigma signal density modulation to reduce electromagnetic interference.

Abstract: An insertable flashlight adapter device for use in an ordinary flashlight having a lamp includes a disc-like shaped housing unit. Electronic circuitry is disposed within the housing unit for selectively operating the flashlight in at least three different modes. The electronic circuitry has a voltage comparator for determining which one of the at least three different modes the flashlight is being operated. The electronic circuitry also has logic and control means for selectively interrupting current to the flashlight lamp so as to cause the at least three different modes of operation. The logic and control means includes a first timer for monitoring a first time interval between mode changes in the voltage comparator and a second timer for monitoring a second time interval between a power-ON and power-OFF state of the flashlight lamp.

Abstract: The present invention discloses a current-matching method comprising steps of: providing a plurality of current channels; grouping the plurality of current channels into W sets, each of which has Q channels; and matching the channels of the same set in current, where both W and Q are integers greater than or equal to 2.

Abstract: An apparatus and method adapted to detect a failure in at least one lamphead of an emergency lighting system includes a signal generator and a failure sensor. The lamphead receives power from a power connection. The signal generator generates a monitoring signal having a voltage which is operatively coupled to the power connection. The failure sensor detects a failure in the lamphead and modifies the voltage of the monitoring signal. The emergency lighting system may also include a plurality of lampheads. In this case, the failure sensor may detect a failure in at least one of the lampheads, and identify which of the plurality of lampheads has failed. The failure sensor may also be adapted to reduce the voltage of the monitoring signal in response to detection of the failure.

Abstract: A ballast integrated circuit (IC) for driving a first switching element and a second switching element includes: a variable gain amplifier (VGA) connected to a first input terminal connected to a resistor, for generating an output current signal according to a resistance value of the resistor and a gain control signal; a preheating/ignition controller connected to a second input terminal connected to a capacitor, for generating an output current signal and an output voltage signal acting as the gain control signal according to a voltage of the second input terminal; an active zero-voltage controller for generating a hard-switching current signal and an active zero-voltage switching current signal, such that it adjusts the voltage of the second input terminal according to switching states of the first switching element and the second switching element; an oscillator for generating an oscillation signal upon receiving the output current signal from the variable gain amplifier (VGA); and a dead-time controller f

Abstract: A circuit arrangement for an LED array having two or more parallel-connected LED chains (LK1, LK2, LK3), in each of which at least one LED (2) is arranged and, when there are two or more LEDs (2), the latter are connected in series. In each case, the anode sides of the LED chains (LK1, LK2, LK3) can be coupled to the positive pole of a supply voltage (Uv) and the cathode sides can be coupled to the negative pole of the supply voltage (Uv). A regulating arrangement (RA1, RA2, RA3) for regulating an intended current distribution between the individual LED chains (LK1, LK2, LK3) is case connected in series with the respective LED chain (LK1, LK2, LK3).

Abstract: A driving device for driving a light source module (12) includes an input current limiting circuit (10) and an inverter (11). The input current limiting circuit includes an input current sensing circuit (100) and a feedback compensation circuit (103), for limiting current of an input power signal of the driving device to a predetermined range. The input current sensing circuit is used for sensing a current signal of the input power signal of the driving device. The feedback compensation circuit is connected to the input current sensing circuit, for outputting a compensation signal according to the sensed current signal. The inverter is connected between the input current limiting circuit and the light source module, and includes a feedback circuit (112). The feedback circuit is connected to the feedback compensation circuit, for receiving the compensation signal and feeding back current flowing through the light source module.

Abstract: A driver circuit for a DC light source supplies a voltage generated by a DC-to-DC converter for a plurality of lamp strings connected in parallel and a plurality of driving currents generated by a current mirror for the lamp strings, such that the lamp strings may have well controlled or uniform brightness.

Abstract: A light quantity adjusting method is used for driving a light emitting device with two drive current levels. The drive current levels are controlled by the first set data and the second set data, respectively. First, a resolution ratio and light quantity characteristics are stored. The resolution ratio represents a ratio between a drive current setting resolution of the first set data and a drive current setting resolution of the second set data. The light quantity characteristics represents a relationship between the first set data and a light emission quantity of the light emitting device. A value in the first set data is obtained as a first set value through adjustment for a quantity of light. Next, a change amount, from the first set value in the first set data is calculated using the light quantity characteristics. The calculated change amount is converted into a value in the second set data as a second set value using the resolution ratio.

Abstract: Disclosed herein is a discharge lamp lighting device which realizes the minute control of the lighting sequence and electric power of a high-pressure discharge lamp and the control of various anti-error protecting functions by mounting a microcomputer. However, since microcomputer processing-typically progresses in accordance with the programs previously recorded on a ROM, various actions of the discharge lamp are controlled in accordance with ROM-recorded data settings. To modify these settings, the contents of the ROM need to be updated. Therefore, a function for communicating with an external device is assigned to the microcomputer so that various data settings can be modified.

Abstract: A light quantity adjusting method is used for driving a light emitting device with two drive current levels. The drive current levels are controlled by the first set data and the second set data, respectively. First, a resolution ratio and light quantity characteristics are stored. The resolution ratio represents a ratio between a drive current setting resolution of the first set data and a drive current setting resolution of the second set data. The light quantity characteristics represents a relationship between the first set data and a light emission quantity of the light emitting device. A value in the first set data is obtained as a first set value through adjustment for a quantity of light. Next, a change amount, from the first set value in the first set data is calculated using the light quantity characteristics. The calculated change amount is converted into a value in the second set data as a second set value using the resolution ratio.

Abstract: The circuit comprises an amplitude setting transistor 5Q for controlling the amplitude of high-frequency current I2QB flowing through the second current mirror circuit 2, by using an input of reference direct current signal Bias. Direct current component I4QB generated based on reference direct current signal Bias is subtracted from direct current I1 flowing through the other side line of the first current mirror circuit 1. In this case, level fluctuation of driving current IZ can be significantly suppressed, since the increment of the direct current component included in high-frequency current I2QB is proportional to direct current component I4QB which is subtracted from direct current I1 flowing through said other side line of the first current mirror circuit 1.

Abstract: An LED array has a plurality of LED chains, which each have at least one LED and are connected in parallel. The LED array has at least one output for feeding back radiation generated to a power supply unit. Preferably, at least one reference LED chain is connected in parallel with the LED chains and a photosensitive component is provided, the photosensitive component detecting the radiation emitted by the reference LED chain. The photosensitive component generates a measurement signal in a manner dependent on the radiation generated by the reference LED chain, which signal serves for providing feedback to the power supply unit.

Abstract: An electronic lamp dimmer includes a burst dimmer circuit and an analog dimmer circuit formed adjacent to each other on an integrated circuit substrate. The burst dimmer circuit controls the illumination intensity of a lamp over a first operating range and the analog dimmer circuit controls the illumination intensity of the lamp over a second operating range that overlaps the first operating range. The electronic dimmer includes a plurality of electrical contacts, each of which is electrically coupled to one of the burst dimmer and analog dimmer circuits and one of which simultaneously provides a dimming control voltage to both of the burst dimmer and analog dimmer circuits.

Abstract: A track lighting hybrid illumination system comprising a power supply circuit (11, 41, 22) having an input for connecting to a voltage source (12, 42) of low frequency for providing an output voltage with altered electrical characteristics, and a pair of conductors (19, 23, 43, 48) coupled to an output of the power supply circuit. A first lamp (29, 25, 31) is coupled to the conductors via a second power supply circuit (28, 26, 34), and at least one further lamp (29, 24, 25, 31) with electrical power requirements of a different characteristic to the first lamp coupled to the conductors.

Abstract: A lighting control system for maintaining a predetermined light level in a lighting zone illuminated by both natural and artificial light includes a CPU connected to an electrical power source and to an electric light. The CPU directs a predetermined initial amount of current to the electric light when the electric light is activated. The system includes a sensor for sensing the light level within the lighting zone and communicating the sensed level to the CPU. Following a comparison of the sensed light level with a predetermined light level, the CPU either increases or decreases the amount of current to the electric light for maintaining the predetermined light level. A thyristor connected to the CPU blocks and releases current flowing to the electric light for gradual power changes. Present light level sensing and current adjustments continue while the electric light is activated.

Abstract: Methods and systems are provided for illuminating a material using an LED system, a processor for controlling the LED system and a positioning system for positioning the LED system in a spatial relationship with the material being illuminated. Furthermore, these methods and systems are available for producing certain color characteristics in an illuminated material or environment. These methods and systems can be applied to a plurality of materials, including biological entities. These methods and systems can be adapted for use in a medical applications, and are advantageously employed for diagnostic and therapeutic interventions.