Abstract: A platform for design of a lighting installation generally includes an automated search engine for retrieving and storing a plurality of lighting objects in a lighting object library and a lighting design environment providing a visual representation of a lighting space containing lighting space objects and lighting objects. The visual representation is based on properties of the lighting space objects and lighting objects obtained from the lighting object library. A plurality of aesthetic filters is configured to permit a designer in a design environment to adjust parameters of the plurality of lighting objects handled in the design environment to provide a desired collective lighting effect using the plurality of lighting objects.

Abstract: The present disclosure provides an analog filament impedance circuit, an LED lamp tube and an LED lighting system, the analog filament impedance circuit having a pole frequency and a zero frequency, where: the pole frequency is less than the zero frequency; an equivalent impedance value of the analog filament impedance circuit remains unchanged when an input frequency is less than the pole frequency, and is a first equivalent impedance value; an equivalent impedance value of the analog filament impedance circuit decreases as the input frequency increases when the input frequency is greater than the pole frequency and less than the zero frequency; an equivalent impedance value of the analog filament impedance circuit remains unchanged when the input frequency is greater than the zero frequency, and is a second equivalent impedance value; and the first equivalent impedance value is greater than the second equivalent impedance value.

Abstract: A strip of linear lighting with distributed power conversion is disclosed. The linear lighting includes a flexible PCB. The flexible PCB is divided into repeating blocks, which are arranged electrically in parallel with one another between power and ground. Each repeating block includes power conversion and conditioning circuits. A plurality of LED light engines are connected to the outputs of the power conversion and conditioning circuits, electrically in series with one another. The power conversion and conditioning circuits typically include at least a full-bridge rectifier, and a filter may be connected to each of the LED light engines. A pair of conductors run the length of the PCB adjacent to it and are connected to each of the repeating blocks. A flexible, transparent covering surrounds the PCB and pair of conductors.

Abstract: An LED lighting module comprises a plurality of serially-connected LED strings, which include N LED strings from a first LED string to an Nth LED string, and each LED string has a specific driven voltage. The control method comprises steps of: (a) receiving an AC voltage signal and converting the AC input signal into a first AC signal; (b) receiving the first AC signal and converting the first AC signal into a first DC signal; and (c) if the first DC signal exceeds the sum of the driven voltages from the first LED string to an nth LED string, driving the serially-connected LED strings from the first LED string to the nth LED string sequentially, wherein n is smaller than or equal to N, so as to adjust the correlated color temperature of the light emitted by the LED lighting module.

Abstract: The invention relates to an optoelectronic circuit intended to receive, between a first node and a second node, a variable voltage, the optoelectronic circuit including: a plurality of light-emitting diodes series-assembled between the first node and a third node; a first current limitation/regulation circuit assembled between the third node and the second node; a switching circuit coupling the third node to at least certain light-emitting diodes of the plurality of light-emitting diodes; a capacitor including first and second plates; a first diode having its cathode connected to the second plate and having its anode coupled to the second node; and a second diode having its anode connected to the second plate and having its cathode coupled to the third node or to a second current limitation/regulation circuit.

Abstract: The light-emitting device disclosed herein comprises a step down circuit and a current limit device, wherein the step down circuit prevents the current signal provided to the light-emitting device larger than the rating current value of the light-emitting device. Moreover, the current limit device only limits current signal while the power supply surges. The two stages protect circuit turn less power to heat.

Abstract: An LED drive device that drives and lights on an LED includes: a power conversion device that converts a voltage of a first power supply, and supplies the voltage to the LED; a second power supply having a voltage lower than a threshold voltage of the LED; a current generation unit that generates current using the voltage of the second power supply, and supplies generated current to an anode of the LED; and a ground-fault detection unit that determines that a ground fault does not occur at the anode of the LED when current does not flow from the current generation unit, and determines that the ground fault occurs at the anode of the LED when current flows from the current generation unit.

Abstract: A open-circuit protection circuit of a constant current driving circuit for light emitting diodes is disclosed, which includes that: a transformer (Ta1), which has at least one secondary winding (WT1), is connected to at least two load branches (A1, A2); a commutating loop is composed of each load branches (A1, A2) and one secondary winding (WT1), wherein the secondary winding (WT1) has tap ends; a current sharing transformer (T1) is set in two neighbor load branch (A1, A2); each load branch (A1, A2) is separately connected to one open-circuit protection module (10).

Abstract: Some embodiments provide a lighting apparatus including a plurality of lighting circuits coupled in series. Each lighting circuit includes a control circuit configured to selectively provide current to at least one LED and at least one charge storage device coupled to the at least one LED. The control circuit may be configured to cause the at least one charge storage device to be selectively charged from a current source and to be discharged via the at least one LED responsive to a varying input. For example, the control circuit may be configured to limit current through the at least one LED to thereby divert current to the at least one charge storage device.

Abstract: A circuit for actuating semiconductor light-emitting elements, wherein the circuit is supplied by a rectified mains voltage, may include at least two series-connected segments, which each have one or more series-connected semiconductor light-emitting elements, wherein the semiconductor light-emitting elements in at least two of the segments are different, which results in different forward voltages of the segments, and in each case one driver for actuating a segment, wherein the driver has at least one electronic switch, by means of which the segment may be bypassed, wherein the circuit arrangement is designed to decide to bypass the segment assigned to the circuit arrangement, on the basis of an instantaneous value of the rectified mains voltage and on the basis of the bypass state of the adjacent segments.

Abstract: A multi-channel constant current source particularly suitable for driving an array of light-emitting diodes as an illumination apparatus provides a power source stage voltage regulator for providing a variable voltage using pulse width modulation as an input to a plurality of constant current driver channels to regulate the constant current provided. Pulse width modulation thus allows both the power source stage and the constant current driver operating frequencies to be decoupled and individually optimized to maintain efficiency while emulating dimming effects of, for example, incandescent bulbs, over a full range of light output flux. Pulse width modulation can also be employed in the constant current channel drivers to avoid chromaticity shift during dimming.

Abstract: A lighting device includes a plurality of light emitting diodes (LEDs) configured to emit a light. The lighting device further includes a color controller configured to repeatedly assert and deactivate a control signal to control whether one or more LEDs of the plurality of LEDs are turned on or turned off. The color controller asserts the control signal for a first time period and deactivates the control signal for a second time period, where a color of the light emitted by the plurality of LEDs depends on the first time period and the second time period. The color controller changes the color of the light emitted by the plurality of LEDs by changing one or both of the first time period and the second time period.

Abstract: Self-identifying solid-state transducer (SST) modules and associated systems and methods are disclosed herein. In several embodiments, for example, an SST system can include a driver and at least one SST module electrically coupled to the driver. Each SST module can include an SST and a sense resistor. The sense resistors of each SST module can have at least substantially similar resistance values. The SSTs of the SST modules can be coupled in parallel across an SST channel to the driver, and the sense resistors of the SST modules can be coupled in parallel across a sense channel to the driver. The driver can be configured to measure a sense resistance across the sense resistors and deliver a current across the SSTs based on the sense resistance.

Abstract: The disclosure provides a lighting device and a voltage reduction method thereof, wherein the lighting device comprises: an AC power supply generator for generating an AC power source to supply power to other accessories and circuits in the lighting device; m load components, every two adjacent load components forming one head common connection point and one end common connection point respectively for each load component from head to end alternatively; and (m?1) current balancing cells each respectively connected between one head common connection point or one end common connection point and one of two output terminals of the AC power supply generator; wherein the m load components comprise (m?n) low impedance load components therein. The present application can reduce the output voltage of the AC power supply generator with lower cost.

Abstract: Disclosed herein is a light emitting diode (LED) driving apparatus including: at least one energy storages connected in series with each other; a plurality of LEDs each connected in parallel with each of the energy storages; and a switching control unit selectively connecting the at least one energy storages according to a level of applied voltage to charge/discharge voltage in/from the selected energy storages and control driving of the LEDs by the charging/discharging operation. Therefore, it is possible to easily drive the LEDs without a converter.

Abstract: A power supply apparatus of an embodiment includes a first filter, a second filter, and a switching power supply. The first filter and the second filter attenuate a common mode current to a level lower than a normal mode current. The switching power supply is connected between the first filter and the second filter, and supplies electric power to an illumination load via the second filter.

Abstract: Some embodiments provide a lighting apparatus including a plurality of lighting circuits coupled in series. Each lighting circuit includes a control circuit configured to selectively provide current to at least one LED and at least one charge storage device coupled to the at least one LED. The control circuit may be configured to cause the at least one charge storage device to be selectively charged from a current source and to be discharged via the at least one LED responsive to a varying input. For example, the control circuit may be configured to limit current through the at least one LED to thereby divert current to the at least one charge storage device.

Abstract: A drive circuit for realizing accurate constant current of multiple LEDs is disclosed. The drive circuit comprises a high-frequency impulse Alternating Current (AC) power carrying N circuit units with same structure. Each of the circuit unit comprises a rectifier filter circuit, a blocking capacitor C1 and two LED loads. The rectifier filter circuit comprises two independent half-wave rectifier circuits, and two filter capacitors. Each of the two half-wave rectifier circuits comprises two diodes connected in series to supply power for the corresponding LED load. The filter capacitor is connected in parallel with the two ends of an LED load respectively, and the blocking capacitor C1 is connected in series with the input end of the rectifier filter circuit. The circuit also comprises N?1 equalizing transformers, each of which connects in series between two adjacent circuit units.

Abstract: A light string includes a plurality of incandescent filament lamps. The incandescent filament lamps are electrically connected in series and powered by an AC power supply. Each incandescent filament lamp is connected in parallel to a capacitor. The capacitors are polarized electrolytic capacitors. A capacitance of each capacitor is 47 microfarads˜120 microfarads. A rated voltage of each capacitor is 16 volts ˜100 volts and is higher than a rated voltage of each incandescent filament lamp. When one of the incandescent filament lamps is failed, the capacitor with which the failed one of the incandescent filament lamps is connected in parallel operates normally and performs power compensation and electrical connection during its repeatedly charging and discharging. When the light string is powered on, the capacitor is charged and absorbs the surge current which may occur. Thus, the voltage dropped on each light rises slowly and the lights are safe.

Abstract: A dimmable solid state lighting apparatus can include a plurality of light emitting diode (LED) segments including a first LED segment that can have a targeted spectral power distribution for light emitted from the apparatus that is different than spectral power distributions for other LED segments included in the plurality of LED segments. An LED segment selection circuit can be configured to selectively control current through the plurality of LED segments to shift the light emitted by the apparatus to the targeted spectral power distribution responsive to dimming input.

Abstract: A lighting apparatus includes a string of Light Emitting Diode (LED) sets coupled in series, each set including at least one LED, a light spreading circuit configured to incrementally turn on respective ones of the LED sets responsive to a power signal, and an energy storage module that is configured to store energy during a first interval of a period of the power signal and to apply the stored energy to the string during a second interval of the period of the power signal.

Abstract: A lighting apparatus includes a solid-state lighting circuit, at least one ballast connection port and at least one low-frequency blocking impedance coupling the at least one ballast connection port to the solid-state lighting circuit. In some embodiments, the at least one low-frequency blocking impedance may be configured to block a DC offset. In further embodiments, the at least one low-frequency blocking impedance may be configured to block a nominally 60 Hz frequency component. The at least one ballast connection port may include a first ballast connection port and a second ballast connection port and the at least one low-frequency blocking impedance may include a first low-frequency blocking impedance coupling the first ballast connection port to a first terminal of the solid-state lighting circuit and a second low-frequency blocking impedance coupling the second ballast connection port to a second input terminal of the solid-state lighting circuit.

Abstract: A LED lighting system, such as a dimmable LED lamp, that may simulate the performance of an incandescent bulb. LED strings of different colors may be connected to the output of a single LED driver that regulates an overall intensity of light produced by the LED lighting system. The color of the LED lighting system may be controlled by circuitry, such as one or more switches, that allocates current between the LED strings to change the color temperature of light emitted by the LED lighting system as the light intensity changes.

Abstract: An apparatus for driving a light emitting diode circuit (1) comprises first and second terminals (11,12) to be connected to the light emitting diode circuit (1), a capacitor (31) connected to the first and second terminals (11,12), a switch (41) for, in a conducting mode, bypassing the light emitting diode circuit (1), and a diode (51) for, in the conducting mode, preventing the capacitor (31)from being discharged via the switch (41). In this way, a reduced switch-on delay is realized without an additional switch being required for activating and deactivating said capacitor (31). The diode (51) is simpler and cheaper and more robust than such an additional switch and does not require a control. Preferably, the apparatus comprises a further terminal (13), wherein the diode (51) is connected to the further terminal (13) and to one of the first and second terminals (11,12), and the switch (41) is connected to the further terminal (13) and to the other one of the first and second terminals (11,12).

Abstract: Some embodiments provide a lighting apparatus including a plurality of lighting circuits coupled in series. Each lighting circuit includes a control circuit configured to selectively provide current to at least one LED and at least one charge storage device coupled to the at least one LED. The control circuit may be configured to cause the at least one charge storage device to be selectively charged from a current source and to be discharged via the at least one LED responsive to a varying input. For example, the control circuit may be configured to limit current through the at least one LED to thereby divert current to the at least one charge storage device.

Abstract: A lighting apparatus includes a solid-state lighting circuit, a ballast connection port including first and second terminals and a filament-imitating impedance coupled between the first and a second terminals of the ballast connection port and to an input terminal of the solid-state lighting circuit. The filament-imitating impedance may be configured to transfer power at a nominal frequency of an output produced by the ballast and to provide an impedance between the first and second terminals of the ballast connection port that prevents shutdown of the ballast. In some embodiments, the filament-imitating impedance may vary with temperature, e.g., the filament-imitating impedance may be configured to imitate a temperature dependence of a fluorescent tube filament. The lighting apparatus may be included in a fluorescent lamp replacement lamp.

Abstract: A low THD load adapter system is disclosed. The load adapter system includes a first lighting module and a second lighting module connected parallel to the first lighting module. During each AC cycle the first lighting module conducts current for a first portion of the cycle and the second lighting module conducts current for a second portion of the cycle. When combined, the total current drawn from the power source substantially tracks the shape of the applied AC voltage. Accordingly, there is minimal distortion, and low total harmonic distortion level is achieved.

Abstract: The present invention provides an isolated boost circuit, a backlight module and a liquid crystal display device. The isolated boost circuit provides power for the LED light string in the backlight module of the liquid crystal display device, which comprises a voltage input terminal, a driving signal unit, a transformer, and a controllable reverse isolation circuit. Wherein, the transformer comprises a primary coil and a secondary coil. The voltage input terminal is connected to the dotted terminal of the primary coil, and the opposite terminal of the secondary coil is connected to the LED light string. The opposite terminal of the primary coil is connected to a 01 terminal of the controllable reverse isolation circuit, the dotted terminal of the secondary coil is connected to a 02 terminal of the controllable reverse isolation circuit, and a 03 terminal of the controllable reverse isolation circuit is connected to the driving signal unit.

Abstract: The present invention relates to a multi-output self-balancing power circuit. In one embodiment, a multi-output self-balancing power circuit can include: a transformer formed by a primary winding and n (e.g., greater than 2) series connected secondary windings; n output circuits corresponding to the n secondary windings, where each of the n output circuits can include a rectifier diode and a filter capacitor, and a load can be parallel coupled with the filter capacitor; n output circuits series coupled between a first output terminal of a first secondary winding and a second output terminal of an nth secondary winding; and (n?1) current balancing capacitors coupled between a common junction of n secondary windings and a common junction of n output circuits.

Abstract: Disclosed are methods and lighting system with LEDs. An exemplified system comprises series-coupled light-emitting diodes, an integrated circuit, and an energy storage apparatus. The series-coupled light-emitting diodes are divided into several LED groups coupled in series. The integrated circuit comprises nodes respectively coupled to the LED groups, for providing a driving current to selectively flow through at least one of the LED groups. The energy storage apparatus has two ends coupled to a predetermined LED in a predetermined LED group. When the driving current flows through the predetermined LED group the energy storage apparatus energizes; and when the driving current does not flow through the predetermined LED group the energy storage apparatus de-energizes to illuminate the predetermined LED.

Abstract: The invention describes an adaptive circuit (1, 1?) for driving a lower-voltage DC load (2) from a rectified higher-voltage AC supply (3), which adaptive circuit (1, 1?) comprises a charge-storage circuit (21, 21?), which charge storage circuit (21, 21?) comprises a first capacitor (C1) and a second capacitor (C2) connected essentially in series, wherein the second capacitor (C2) is connected at least in parallel with the load (2); and an active switch (22, 22?) realized as a controlled current source (22, 22?) for controlling a load current (Iload) through the load (2) such that, in a closed switch state, load current (Iload) is drawn essentially from the first capacitor (C1) of the charge-storage circuit (21, 21?), and, during an open switch state, load current (Iload) is drawn essentially from the second capacitor (C2).

Abstract: An inductorless LED driver powers a string of low current LEDs. A phase controlled triac dimmer, serially connected to a full-wave rectifier circuit, performs as an LED current and triac holding current control element. The output of the full-wave rectifier circuit is divided into two circuit paths; the first path provides power to drive a string of serially-connected low-current LEDs, and the second path connects to a dynamic load, which supplies a holding current that flows through the triac dimmer. There are two feedback control systems; the first regulates the luminance of the LEDs; the second regulates the triac holding current to eliminate lamp flicker.

Abstract: An LED backlight device includes an inverter having an input connected to a DC power supply to provide an output AC current. A plurality of transformers are each configured to drop AC current input from the inverter. Input sides of the transformers are connected in series to an output of the inverter and output sides of the transformers are disposed in parallel. A plurality of full-wave rectification circuits are respectively connected to the output sides of the transformers and full-wave rectify the dropped AC currents, respectively. A plurality of smoothing circuits are respectively connected to outputs of the full-wave rectification circuits, and are configured to smooth the full-wave rectified currents to output DC currents, respectively. A plurality of LED strings are respectively connected to the outputs of the smoothing circuits and each of the LED strings have a plurality of LEDs.

Abstract: A lighting apparatus includes a rectifier circuit configured to be coupled to an AC source and to produce a rectified voltage from an AC voltage and a string including at least two serially-connected LED segments and coupled to the rectifier circuit. A segment control circuit is configured to selectively bypass at least one segment of the string responsive to the rectified voltage. An energy storage circuit is coupled to the rectifier circuit and controls current flow between at least one energy storage device and the string. A control circuit controls the segment control circuit and the energy storage circuit. The segment control circuit may support a current from the rectifier circuit through all of the segments in the string circuit at a peak of the rectified voltage and the energy storage circuit may charge the at least one energy storage device to a voltage near the peak of the rectified voltage.

Abstract: According to one embodiment, a luminaire includes a light-emitting module. The light-emitting module includes a light-emitting element and a capacitive element. The capacitive element is connected to the light-emitting element in parallel. The capacitive element has a withstand voltage higher than a breakdown voltage of the light-emitting element.

Abstract: A light-emitting device and an illumination apparatus are disclosed. A plurality of LED elements are connected in series between positive and negative lines, and first bypass capacitor is connected in parallel to the LED elements respectively. Each series circuit of a predetermined number of LED elements is connected in parallel to second bypass capacitors. As a result, with the negative power line set as a grounding point, the AC impedance at connection points of the series circuit of the LED elements against the ground is reduced. Thus, the erroneous lighting or “flicker” of each LED which otherwise might be caused by an external noise is prevented.

Abstract: A control circuit (1) for light emitting diode arrangements (11), used particularly for backlighting LC flat screens. The circuit has a plurality of control channels (5, 5?) in each of which one or more light emitting diode arrangements (11) are disposed. The circuit has a balancing device (23) which allows currents in the individual control channels (5, 5?) to be balanced. Each control channel (5, 5?) has a separate dimming device (13) through which a brightness of the light emitting diode arrangements (11) in this control channel (5, 5?) can be changed separately from the other control channels (5, 5?). For this purpose, the control circuit has a compensation device (16) which allows a flow of current in the individual control channels (5, 5?) to be balanced when the light emitting diodes have different brightnesses.

Abstract: A circuit for actuating a plurality of light-emitting means which are connected in series, comprising a plurality of electronic switches, which can be actuated depending on a rectified system voltage. The plurality of electronic switches are arranged in parallel with at least some of the light-emitting means, wherein each of the plurality of electronic switches short-circuits on activation of at least one of the light-emitting means connected in series. At least one energy store is connected in parallel with a first group of light- emitting means during a charge phase by virtue of the electronic switches, and it is connected in parallel with a second group of light-emitting means during a discharge phase by virtue of the electronic switches.

Abstract: Provided is an AC LED light emitting device. The AC LED light emitting device flows a current to at least one AC LED array among at least two AC LED arrays of an AC LED light emitting unit to turn it on during one period of an AC power having sine wave characteristics if a magnitude of a voltage applied to the AC LED light emitting unit including at least two AC LED arrays each of which including at least one AC LED is smaller than a turn-on voltage determined according to the number of AC LED arrays of the AC LED light emitting unit. If the magnitude of the voltage applied to the AC LED light emitting unit is larger than the turn-on voltage of the AC LED light emitting unit, all of the AC LED arrays of the AC LED light emitting unit are turned on.

Abstract: An LED lighting system has an LED circuit that includes a first LED having an anode and a cathode, and a second LED having an anode and a cathode. The anode of the second LED is electrically coupled to the cathode of the first LED, and the cathode of the second LED is electrically coupled to the anode of the first LED. The first and second LEDs are in an inverse-parallel arrangement, the first LED acting as a reverse-voltage clamp for the second LED and the second LED acting as a reverse-voltage clamp for the first LED.

Abstract: The present invention provides an illumination device, an illumination system, and a lamp. The illumination system includes the illumination device and a light modulation module. The illumination device includes a light emitting diode (LED) array, an alternating current (AC) current source, and an output power control module. The AC current source is electrically coupled to the LED array. The output power control module is electrically coupled to the LED array and the AC current source. The LED array, the AC current source, and the output power control module together form a closed-loop control loop. The light modulation module is electrically coupled to the closed-loop control loop for modulating illumination brightness of the LED.

Abstract: A flicker-free LED driver circuit with a high power factor has a rectifying unit connected with an AC power source, an LED module connected in series with the rectifying unit, a capacitor module connected in parallel with the LED module, and a constant current circuit connected in series with the LED module and the capacitor module. When the voltage output by the rectifying unit is smaller than a junction voltage of the LED module, the capacitor module discharges to the LED module so that the LED module does not go out, thereby eliminating the flickering. The input impedance of the rectifying unit can be regarded as a capacitive reactance element connected in parallel with a nonlinear resistive element. The internal resistance of the constant current source approaches infinity. Therefore, the power factor of the flicker-free LED driver circuit approximates 1, achieving a high power factor.

Abstract: The present invention relates to a multi-output self-balancing power circuit. In one embodiment, a multi-output self-balancing power circuit can include: a transformer formed by a primary winding and n (e.g., greater than 2) series connected secondary windings; n output circuits corresponding to the n secondary windings, where each of the n output circuits can include a rectifier diode and a filter capacitor, and a load can be parallel coupled with the filter capacitor; n output circuits series coupled between a first output terminal of a first secondary winding and a second output terminal of an nth secondary winding; and (n?1) current balancing capacitors coupled between a common junction of n secondary windings and a common junction of n output circuits.

Abstract: The disclosed implementations utilize the voltage drop inherent in the device string to power a device control IC. In some implementations, current is drawn from the bottom of the device string and applied to a voltage supply pin of the device control IC. In some implementations, current is drawn from some other location in the device string (e.g., near the bottom or midpoint of the device string) using a switch. In some implementations, current is drawn from near the bottom and the bottom of the device string at different times, such that less current is drawn from the bottom of the device string as the duty cycle of the device string increases and more current is drawn from near the bottom of the device string as the duty cycle of the device string increases.

Abstract: A light-emitting diode (LED) driver used to power at least one LED with an alternating current (AC) voltage source is provided. The LED driver includes a rectifying unit applying N-fold higher voltage than the voltage from the AC voltage source to the LED. The rectifying unit includes a first charging unit to charge a first voltage, and a second charging unit to charge a second voltage. The first voltage includes the voltage at the AC voltage source during a first half-cycle of one AC voltage cycle, and the second voltage includes the first voltage and the voltage at the AC voltage source during the second half-cycle of the AC voltage cycle. Accordingly, the LED driver may improve light-emitting efficiency and reduce flicker of LEDs.

Abstract: Disclosed herein is a light emitting diode (LED) driving apparatus including: at least one energy storages connected in series with each other; a plurality of LEDs each connected in parallel with each of the energy storages; and a switching control unit selectively connecting the at least one energy storages according to a level of applied voltage to charge/discharge voltage in/from the selected energy storages and control driving of the LEDs by the charging/discharging operation. Therefore, it is possible to easily drive the LEDs without a converter.

Abstract: Some embodiments provide a lighting apparatus including a plurality of lighting circuits coupled in series. Each lighting circuit includes a control circuit configured to selectively provide current to at least one LED and at least one charge storage device coupled to the at least one LED. The control circuit may be configured to cause the at least one charge storage device to be selectively charged from a current source and to be discharged via the at least one LED responsive to a varying input. For example, the control circuit may be configured to limit current through the at least one LED to thereby divert current to the at least one charge storage device.

Abstract: An LED power supply device may include a power supply to control an LED component, a control unit to control the power supply, the control unit having a control interface for applying external control signals to the power supply, and a voltage supply unit connected to a connection of the power supply, wherein the control unit receives operating voltage from the voltage supply unit for continuous operation in an activated and non-activated control state of the LED component, wherein the voltage supply unit comprises a capacitor coupled to an output side of the power supply, the capacitor configured to supply a capacitor voltage as operating voltage to the LED power supply device, and wherein the control unit is configured to charge the capacitor using pulse-like control of the power supply such that, in the non-activated control state, a maximum charging voltage lies below the LED threshold voltage.

Abstract: A drive circuit for realizing accurate constant current of multiple LEDs is disclosed. The drive circuit comprises a high-frequency impulse Alternating Current (AC) power carrying N circuit units with same structure. Each of the circuit unit comprises a rectifier filter circuit, a blocking capacitor C1 and two LED loads. The rectifier filter circuit comprises two independent half-wave rectifier circuits, and two filter capacitors. Each of the two half-wave rectifier circuits comprises two diodes connected in series to supply power for the corresponding LED load. The filter capacitor is connected in parallel with the two ends of an LED load respectively, and the blocking capacitor C1 is connected in series with the input end of the rectifier filter circuit. The circuit also comprises N?1 equalizing transformers, each of which connects in series between two adjacent circuit units.

Abstract: A constant current driving circuit of a light emitting diode (LED) including a control unit, a buck converter, and a compensation unit is provided. The control unit has an input terminal and an output terminal, and outputs a control signal through the output terminal. The buck converter is coupled to an input power, and is coupled between the output terminal of the control unit and an LED string. The compensation unit is coupled between the LED string and the input terminal of the control unit. The control unit receives a compensation signal of the compensation unit through the input terminal. Besides, a lighting apparatus is also provided.