Abstract: The present disclosure discloses a method based on microcontroller circuit and software codes to on line automatically detect the time phase of the threshold voltage of a lighting load in each AC half-cycle. This automatic detection capability enables a dimmer circuit of a lighting apparatus to establish a dimmer working range from the self-detected time phase of threshold voltage of the lighting load. The lighting apparatus can be operated with different types of lighting loads to perform a full dimming range from 0% to 100% of maximum lighting output. Therefore, the dimmer circuit makes possible both the lighting fixtures and the users refrained from dimming difficulties caused by different types of lighting loads with different threshold voltages. The design concept can be extended to manage illuminations in a two-level security light on a simple software basis without resorting to complex electric circuits.

Abstract: An LED driver circuit is provided with a dynamic operating range which can be set using an offline tuning interface. During an online mode of operation, a controller for a power converter is configured to regulate the output voltage and the output current generated by the power converter based on a dimming control signal from a dimming control interface, a sensed output from the power converter, and programmed maximum output voltage and maximum output current values. During an offline mode of operation, the tuning interface may be coupled to the dimming control interface and provides a sequence of digital pulses corresponding to a desired maximum output voltage and/or maximum output current. The controller then modifies the programmed maximum output voltage and the maximum output current values based on the predetermined sequence of digital pulses received via the tuning interface circuit.

Abstract: A method is provided for detecting and correcting improper operation of a lighting system including a solid state lighting load. The method includes detecting first and second values of a phase angle of a dimmer connected to a power converter driving the solid state lighting load, the first and second values corresponding to consecutive half cycles of an input mains voltage signal, and determining a difference between the first and second values. When the difference is greater than a difference threshold, indicating asymmetric waveforms of the input mains voltage signal, a selected corrective action is implemented.

Abstract: Devices and methods for monitoring and determining alternating current (AC) power system parameters are provided. In some implementations, the device can include a processor; and at least one non-transitory computer-readable medium storing computer-executable instructions for implementing a number of components. The components include a monitor configured to: sense an AC line voltage signal and an AC current voltage signal; filter the AC line voltage signal; calculate average AC line voltage and current values based, at least, on a DC voltage and current values corresponding to the AC line voltage and current signals, respectively; determine fundamental AC line voltage and current signals based, at least, on zero crossings of the respective average AC line voltage value and the average AC line current value; and determine one or more AC power system parameters based, at least, on the fundamental AC line voltage signal and the fundamental AC line current signal.

Abstract: A method for controlling a power source semiconductor may include: supplying, by a switching frequency supply unit, preset respective reference switching frequencies to a plurality of elements which are operated according to a respective switching frequency; sensing, by a control unit, sensing interference in the plurality of elements, based on operations of the elements according to the respective reference switching frequencies; setting, by the control unit, bandwidths for the respective reference switching frequencies when the interference in the plurality of elements is sensed; and increasing, by a bandwidth adjusting unit, bandwidth of the respective reference switching frequencies supplied through the switching frequency supply unit, based on the bandwidths for the respective reference switching frequencies.

Abstract: In order to regulate an illuminance, an actual value of a sensor (3) is queried, said value being dependent on the illuminance to be regulated and being regulated to a setpoint value. In a control step, an electronic computing device (11) determines an actuating step for an illuminant (2) on the basis of said actual value and a parameter value of a control parameter. The electronic computing device (11) determines a new parameter value of the control parameter for a subsequent control step on the basis of a first actual value which is received before the corresponding control step, and a second actual value which is determined after the corresponding control step.

Abstract: An alternating current detector with automatic judging of the amount of element under testing and monitoring, comprising a detecting input unit, a first output level unit, a second delay unit, a second output level unit and a cascade next element unit. The detecting input unit comprises a first delay unit and a first inverter. The first delay unit receives and delays an input signal. The input terminal of the first inverter is connected to the first delay unit and inverts the input signal. The first output level unit comprises a first NAND gate, a first diode and first resistor. The input terminal of the first NAND gate is connected to the alternating current signal of an element, another input terminal of the first NAND gate is connected to the output terminal of the first inverter.

Abstract: Aspects of the present invention relates to a solar powered LED lighting system for an umbrella. In certain embodiments, the solar powered LED lighting system has (a) a rechargeable battery, (b) a solar panel, (c) one or more LED lights, (d) one or more touch control sensors, and (e) an unipath touch control circuit. The rechargeable battery is used to provide electricity to the solar powered LED lighting system. The solar panel converts optical energy to electrical energy and charges the rechargeable battery. The LED lights are installed on the umbrella to provide lighting. The touch control sensors are used to sense a user's touch event, and responsively generate a control signal. The unipath touch control circuit receives the control signals from the touch control sensors, and controls the solar powered LED lighting system according to the received control signal.

Abstract: A controller for a driver circuit of a solid state lighting (SSL) device is described. The driver circuit comprises a power converter to transfer energy from AC mains voltage to the SSL device. The controller determines a dim level for the SSL device. The controller also determines a synchronization signal by comparing a voltage derived from the input voltage with a pre-determined threshold. The controller determines a sequence of PWM pulses based on the synchronization signal. The controller operates the power converter in a first operation mode for supplying energy to the SSL device at a first energy level within the sequence of PWM pulses, and operates the power converter in a second operation mode in between the PWM pulses. The second energy level is lower than the first energy level and the first energy level and/or a width of the PWM pulses depend on the dim level.

Abstract: A dynamic high-energy switch used for correcting load imbalance through connecting and disconnecting capacitance in a power feed circuit.

Abstract: High frequency ballasts are provided herein for ignition control of a ceramic high intensity discharge (HID) lamp. A sensor senses a lamp parameter on the output terminals. A microprocessor is attached to the ignition circuit and the sensor. The ignition circuit is configured by the microprocessor to apply a train of pre-ignition bursts to the electrodes and stop the train of pre-ignition bursts responsive to measurement of the lamp parameter. The measured lamp parameter is indicative of a stable arc at the proximal ends of the capillaries.

Abstract: A gestural control dimmer switch for controlling the illumination level of a light using hand movements includes a dimmer panel having a continuum of positions associated with a spectrum of illumination levels of the light. Hand position sensors produce a hand position detection field in front of the continuum of positions of the dimmer panel through which a hand can be passed. No dimming input is produced by a hand passing through the hand position detection field until the hand passing through the detection field reaches a set trigger position at one of the continuum of positions along the dimmer panel. A dimming input is only produced in response to changes in hand position in the hand position detection field after the hand reaches the trigger position. A new trigger position is set after the illumination level of the light controlled by the dimmer switch is adjusted.

Abstract: An electronic timepiece includes a display section which displays time information and a light emitting section which illuminates a display surface of the display section by emitting light. A light emitting control section performs control to turn on the light emitting section by gradually increasing a light emitting amount of the light emitting section to a peak value in a predetermined brightening time according to a predetermined light emitting condition.

Abstract: A lamp dimmer system for dimming multiple lamps in a room having unswitched receptacles, and switched receptacles under control of a single wall switch. A user control module connected to an unswitched receptacle transmits momentary wireless brightness command signals in response to user-actuation of a brightness control. Each lamp in the room includes a lamp control module connected to both the unswitched and switched receptacles and to the lamp. The lamp control modules include a receiver which receives the brightness command signals and a control circuit which generates a steady state brightness control signal in response to the momentary command signals. A dimmer circuit responsive to the brightness control signal, and connected between the unswitched receptacle and the lamp, controls the power supplied to the lamp according to the level of the brightness control signal.

Abstract: A system and method are disclosed for dimming light emitting diode (LED) lamps. A control unit is coupled to a dimmer and LED lamp. The dimmer receives power from an AC source and determines a phase angle of the AC power. The dimmer provides DC power to the lamp based on the phase angle. The control unit sends a control signal to the dimmer during a first portion of each half sine-wave of the received AC power. The control signal causes the dimmer to modify at least one function of the lamp. A plurality of LED lamps may be associated with a single dimmer, and the dimmer may individually instruct the lamps to modify their operational characteristics. The dimmer may send an operational signal back to the control unit. The operational signal may represent end of life information for the associated LED lamp. Other embodiments are described and claimed.

Abstract: A constant current source has an increased differential amplifier gain at low output currents and a decreased differential amplifier gain at high output currents. The differential amplifier amplifies a sensed output current of the constant current source. A gain control circuit scales a reference current in conjunction with the gain applied to the sensed output current to maintain stable operation of the constant current source. The constant current source may be used in a driver circuit to provide power to a light source (e.g., an LED light).

Abstract: A dimmable alternating current (AC) driven light emitting diode (LED) illuminating apparatus including a TRIAC dimmer configured to perform a dimming control using a phase control.

Abstract: A dimming way without turning on/off is to change output voltage for LED or OLED lamp corresponding to dimming percentage without turn on and off LED or OLED lamp; The dimming control signal can come from a keyboard, a phase dimmer, a dimmer button or a computer; The dimming control signal can be sent to controller through PWM signal, phase dimmer or I2C; The output load can be LED lamp or OLED lamp.

Abstract: In embodiments, improved capabilities are described for dimming performance of lighting methods and systems, such as the improvement of dimming LED lamps that are dimmed from standard external dimming devices. Methods and systems for improving dimming performance include a fast startup override facility for overriding a default dimming function of the lamp's electronics through forcing the lamp electronics to operate with a higher than normal duty cycle to ensure the lamp electronics can deliver higher than normal power to an LED module during a dimming current level startup condition. Dimming facilities may also include a dynamic RC selection facility, an active N-level bleeder facility, a dimmer-type detection facility, an improved dimming linearity through symmetrical phase cutting facility, and a flicker reduction facility.

Abstract: An AC/DC converter is disclosed. The proposed AC/DC converter generates an output voltage and includes a current ripple eliminator having an input terminal, an energy storage capacitor and an output terminal, wherein the input terminal has an input voltage, the output terminal generates a pure AC component of a voltage feedback signal based on the output voltage, when the input voltage is larger than a first reference voltage, the energy storage capacitor stores a difference between the input voltage and the first reference voltage as an electric energy, otherwise, the energy storage capacitor releases the electric energy to the input voltage, and an operational amplifier operating the AC component and a second reference voltage to determine when the storage capacitor should store or release the electric energy to minimize a ripple of an output power thereof.

Abstract: In one embodiment, an active power factor correction (APFC) control circuit, configured to generate a pulse-width modulation (PWM) control signal to control the operation of a power converter, can include: (i) an inductor current zero crossing detection circuit coupled to a common node between a power switch of the power converter and a first switch that are coupled in series, where the inductor current zero crossing detection circuit is configured to generate a comparison signal based on a voltage signal at the common node; (ii) the comparison signal being activated when an inductor current of the power converter decreases to zero; and (iii) the APFC control circuit being configured as a source driver, wherein a control terminal of the power switch is coupled to a constant voltage supply.

Abstract: A soft start device for a power cutting machine tool, a control circuit group includes two end, one of which is connected with an input power source and the other is connected with each of two control switches. When the input power source provides a working voltage for the control circuit group, the control circuit group outputs a low-level signal to the control switches to enable a light emitting circuit group to lighting gradually from dark to light, whereby a resistance of a trigger circuit group decreases gradually to make motor setup the working voltage. Next, the control circuit group outputs a high-level signal after a period of time, to turn on the control switches for inputting voltage to the motor directly. The soft start device can not only decrease the noise during activation of the motor but effectively protect the internal components of an electronic device from damage.

Abstract: In at least one embodiment, a system and method provide current compensation in a lighting system by controlling a lamp current to prevent a current through a triac-based dimmer from undershooting a holding current value. In at least one embodiment, at least one of the lamps includes a controller that controls circuitry in the lamp to draw more lamp current for a period of time than needed to illuminate a brightness of the lamp at a level corresponding to particular phase-cut angle of the supply voltage. By drawing more current than needed, the controller increases the dimmer current during the period of time to prevent the dimmer current from falling below the holding current value. In at least one embodiment, the period of time corresponds to a compensating pulse of the lamp current at a time when the dimmer current would otherwise fall below the holding current value.

Abstract: An electric receptacle capable of operating in a dimmable mode and a standard mode comprises an opening for receipt of an adapter. The adapter is received by the electric receptacle and switches the electric receptacle from the standard mode to the dimmable mode. The adapter is dimensioned to fit over a standard plug and the electric receptacle is configured to receive a standard plug.

Abstract: A circuit with adjustable phase delay and a feedback voltage includes a delay setting unit and a phase delay signal generator. The delay setting unit generates a delay time according to an external resistor. The phase delay signal generator includes a plurality of phase delay units. Each phase delay unit includes an edge trigger subunit and a signal generation subunit. The edge trigger subunit receives an input signal, and generates a positive edge trigger signal and a negative edge trigger signal according to a positive edge and a negative edge of the input signal, respectively. The signal generation subunit generates and outputs a phase delay signal according to the positive edge trigger signal, the negative edge trigger signal, and the delay time. The phase delay signal lags the input signal for the delay time.

Abstract: A method for transmitting control information from a control apparatus to an operating device for a light-emitting means may include a) modulating control information onto a supply line by means of the control apparatus during a modulation phase, wherein a switchable shunt of the device is connected between the first and second supply connections; b) decoding the control information in a decoder of the device; b1) activating the demodulation by the decoder when the absolute value for the voltage at the two supply connections falls below a first threshold value; and c) actuating a converter of the operating device in accordance with the decoded control information.

Abstract: Exemplary systems, methods and apparatuses for providing dimming in a distributed solid-state lighting system are disclosed. An exemplary dimming signal generator is coupleable to a controller or a current generator for a plurality of LEDs, and includes a first resistive voltage divider to sense an input DC voltage; a current sensor to sense a current level of the plurality of LEDs; a first operational amplifier to compare the sensed input DC voltage to a reference voltage level and to provide a comparator output signal; and a current path to combine the comparator output signal with the sensed LED current level to provide a combined signal for current level feedback for control of the LED current level. The dimming signal generator may optionally include other components to generate a PWM signal and also to provide a resistive network to divert LED current in response to the comparator output signal.

Abstract: Switched-mode power supply device having an input for receiving an AC voltage input signal, an output for providing a DC voltage signal and/or a direct-current signal to a downstream consumer, a transformer having a primary winding and a secondary winding, and resonant converter means assigned to the primary side of the transformer, which resonant converter means form an LLC topology with inclusion of the primary winding and can be actuated with a variable-frequency control signal on the primary side by means of a control unit, wherein the control unit, which is realized by means of an integrated and/or programmable circuit component, generates the control signal in reaction to and as a function of a zero-crossing detection signal generated from the AC voltage input signal, a current flowing in the transformer windings, in particular on the secondary side, and a constant and/or predeterminable preset signal for an output current flowing at the output, in such a way that regulating means associated with the co

Abstract: In at least one embodiment, an electronic system adapts current control timing for half line cycle of a phase-cut input voltage and responsively controls a dimmer current in a power converter system. The adaptive current control time and responsive current control provides, for example, interfacing with a dimmer. The electronic system and method include a dimmer, a switching power converter, and a controller to control the switching power converter and controls a dimmer current. In at least one embodiment, the controller determines a predicted time period from a zero crossing until a leading edge of a phase-cut input voltage and then responsively controls the dimmer current to, for example, reduce current and voltage perturbations (referred to as “ringing”), improve efficiency, and reduce an average amount of power handled by various circuit components.

Abstract: A driving circuit includes a first PWM driving module and a second PWM driving module. The first PWM driving module generates a first square-wave signal to drive a first illumination unit according to a first data signal of a data stream, wherein the first square-wave signal, having a rising edge located at the beginning of the display cycle, represents an illumination period of the first illumination unit in a display cycle. The second PWM driving module generates a second square-wave signal to drive a second illumination unit according to a second data signal of the data stream, wherein the second square-wave signal, having a falling edge located at the end of the display cycle and having a rising edge being behind the rising edge of the first square-wave signal, represents an illumination period of the second illumination unit in the display cycle.

Abstract: A load control device (such as, a dimmer switch) for controlling the amount of power delivered from an AC power source to an electrical load (such as, a high-efficiency lighting load) includes a thyristor coupled between the source and the load, a gate coupling circuit coupled to the gate of the thyristor, a control circuit, and an RF receiver for receiving an RF signal. The control circuit causes the gate coupling circuit to conduct a gate current to render the thyristor conductive at a firing time during a half cycle of the AC power source, and allows the gate coupling circuit to conduct the gate current at any time from the firing time through approximately the remainder of the half cycle. The thyristor is able to remain conductive independent of the magnitude of a load current conducted through the thyristor and to conduct the load current to and from the electrical load during a single half-cycle.

Abstract: A system and method for controlling the dimming of a lighting element, or other electrical load, that uses a timer synchronized to the AC waveform is disclosed. The timer is set up to repeatedly count at a rate equal to twice the frequency of the AC waveform. An output from the timer logic is asserted when the timer value exceeds a predetermined value, stored in a compare register. This output is connected to the gate of a triac, which controls the passage of current from the AC power source to the electrical load. A capture register is used to determine the temporal relationship between the restart of the timer and the AC waveform. This system and method reduces the real time requirements of an associated processing unit, and improves consistency, thereby reducing flicker.

Abstract: An LED backlight includes a light emitting unit, a driver, a current divider, and a power supply unit. The lighting unit includes a plurality of LEDs connected in series. The driver is connected in series with the LEDs and configured to control driving of the light emitting unit. The current divider is connected in parallel to the driver of a series circuit including the light emitting unit and the driver. The power supply unit is configured to apply a voltage to the series circuit.

Abstract: A lamp including a first set of light emitting diodes configured to generate first light, a second set of light emitting diodes configured to generate second light, and a third set of light emitting diodes configured to generate third light. The first light, the second light, and the third light combine to produce white light. A first switch is located at a base portion of the lamp. The state of the first switch corresponds to a color temperature of the white light. A color temperature adjustment module is configured to vary outputs of the first, second, and third sets of light emitting diodes in accordance with the color temperature of the white light selected by a user using the first switch.

Abstract: The semiconductor device is included in the LED driving circuit (current regulator) of driving the LED array (with series-connected number m×parallel-connected number n), and is formed of a plurality (n pieces) of LED driving devices of controlling a current (constant-current driving) flowing in each string. A vertical semiconductor device, for example, a vertical MOSFET is used as the LED driving device. Both of a main device functioning as a constant-current driving device and a subsidiary device functioning as a circuit-breaking switch during dimming are formed inside a chip of the device, which are formed of the vertical semiconductor devices. In a first surface of the device, each source region of the main device and the subsidiary device is formed so as to be insulated from each other through an isolation region.

Abstract: A direction indication lamp control device includes: a current control element including an end which outputs a drive current having a magnitude corresponding to amplitude of a pulse signal; a current clamp unit which limits the drive current to a current upper limit value; a voltage clamp unit which limits a reference voltage to a voltage upper limit value; and a wire disconnection detection unit which outputs a wire disconnection detection signal in a case where the drive current corresponding to the pulse wave of the pulse signal is equal to or less than a wire disconnection detection value, or in a case where the reference voltage is equal to the voltage upper limit value. The current upper limit value is smaller than the drive current flowing through a direction indication lamp when the reference voltage is the voltage upper limit value.

Abstract: A driving circuit for a solid state lighting apparatus includes a full wave rectifier configured to rectify an alternating current (AC) input voltage signal to generate a rectified input signal, a boost conversion circuit configured to receive the rectified input signal and responsively generate a direct current (DC) output voltage signal and to supply the output voltage signal to a solid state light source, and a boost control circuit coupled to the boost conversion circuit and configured to cause the boost conversion circuit to operate in a constant power mode.

Abstract: A driver circuit for driving an LED includes a rectifier circuit to receive AC voltage and to convert the AC voltage to DC voltage. The driver circuit further includes a filter circuit for filtering the DC voltage. The driver circuit further includes a detection circuit for determining a change in the filtered DC voltage over a predetermined time interval. The driver circuit further includes a dampening circuit for dampening the filtered DC voltage responsive to the detection circuit determining that the change in filtered DC voltage over the predetermined time interval exceeds a predetermined threshold.

Abstract: The present invention relates to a method for driving and to an associated command and control device for discharge lamps (2), for example high pressure sodium lamps (2), supplied by an alternating current electrical supply network. Both the method and the device provide the use of an electronic microprocessor (7) receiving on the input side data relating to the current drawn by the lamp (7) and connected on the output side to a power switch (6) for high frequency switching of the alternating current supply to the lamp.

Abstract: The invention discloses an illumination control circuit and an illumination control method. The illumination control method includes modulating an alternating current input signal and accordingly generating a dimming signal, which includes several waveform pulses each with an adjustable conduction angles; continuously sampling the waveform pulses of the dimming signal and forming an average waveform pulse from the sampled waveform pulses; extracting the average waveform pulse, which has an average conduction angle corresponding to the conduction angles of the waveform pulses; performing an integration on the sampled average waveform pulse and accordingly generating a current-controlling signal; and driving an illumination lamp according to the current-controlling signal.

Abstract: A two-wire load control device (such as, a dimmer switch) for controlling the amount of power delivered from an AC power source to an electrical load (such as, a high-efficiency lighting load) includes a thyristor coupled between the source and the load, a gate coupling circuit coupled between a first main load terminal and the gate of the thyristor, and a control circuit coupled to a control input of the gate coupling circuit. The control circuit generates a drive voltage for causing the gate coupling circuit to conduct a gate current to thus render the thyristor conductive at a firing time during a half cycle of the AC power source, and to allow the gate coupling circuit to conduct the gate current at any time from the firing time through approximately the remainder of the half cycle, where the gate coupling circuit conducts approximately no net average current to render and maintain the thyristor conductive.

Abstract: A bleeder arrangement for a phase-cut circuit for a high-impedance load and having a leading-edge phase-cut device is disclosed, the bleeder arrangement comprising: a controllable current sink adapted to sink a latching current through the leading-edge phase-cut device, and a controller for controlling the controllable current sink, wherein the controller is configured to disable the current sink after the leading-edge phase phase-cut device has latched in at least two stages. A controller for use in such an arrangement is also disclosed, as is a method of controller such a bleeder arrangement.

Abstract: An exemplary embodiment of the present invention relates to an active damper and a driving method thereof. An AC input passed through a dimmer is transmitted to an active damper through a rectification circuit. The active damper includes a damper resistor connected to the rectification circuit, a damper switch connected to the damper resistor in parallel, and a delay circuit delaying a turn-on time of the damper switch by a predetermined initial period from a turn-on time of the dimmer.

Abstract: Method and apparatus for providing controllable power to the load via AC-line power source where load is less than minimal required for proper operation of said source. In one example LED lamp connected to AC power source via conventional triac-based dimmer uses less power than minimum required for proper operation of said dimmer. In another example LED lamp connected to AC power source via device known as electronic transformer uses less power than required for proper operation of said electronic transformer.

Abstract: The present invention discloses a light emitting device power supply circuit, a light emitting device driver circuit and a control method thereof. The light emitting device driver circuit is coupled to a tri-electrode AC switch (TRIAC) dimmer circuit, and it controls the brightness of a light emitting device circuit according a rectified dimming signal. The light emitting device driver circuit includes a power stage circuit and a light emitting device control circuit. The light emitting device control circuit generates a switch control signal. The power stage circuit operates at least one power switch thereof according to the switch control signal to generate a latching current for firing the TRIAC dimmer circuit, and the latching current is inputted to the light emitting device circuit.

Abstract: A two-wire load control device (such as, a dimmer switch) for controlling the amount of power delivered from an AC power source to an electrical load (such as, a high-efficiency lighting load) includes a thyristor coupled between the source and the load, a gate coupling circuit coupled between a first main load terminal and the gate of the thyristor, and a control circuit coupled to a control input of the gate coupling circuit. The control circuit generates a drive voltage for causing the gate coupling circuit to conduct a gate current to thus render the thyristor conductive at a firing time during a half cycle of the AC power source, and to allow the gate coupling circuit to conduct the gate current at any time from the firing time through approximately the remainder of the half cycle, where the gate coupling circuit conducts approximately no net average current to render and maintain the thyristor conductive.

Abstract: A load control device, such as an electronic ballast, for controlling the power delivered from an AC power source to an electrical load, such as one or more fluorescent lamps, comprises a power converter having an inductor and a power switching device coupled to the inductor, a load control circuit adapted to be coupled to the electrical load, and a control circuit operable to calculate an average input power of the load control device. The control circuit may be operable to calculate a cumulative output power of the power converter while the ballast is preheating filaments of the lamps, and to subsequently determine a fault condition in the lamps in response to the calculated cumulative output power of the power converter. Further, the control circuit may be operable to transmit a digital message including the calculated average input power of the load control device.

Abstract: The present invention discloses a digital dimming device and a digital dimming method, for controlling a plurality of light emitting device channels. The method comprises: generating a corresponding plurality of driving signals to control the plurality of light emitting device channels; receiving a PWM input signal having a duty ratio, and phase shifting the PWM input signal to generate multiple PWM output signals with about the same duty ratio as the PWM input signal, but with respectively shifted phases; and enabling or disabling corresponding driving signals by the multiple PWM output signals, respectively.

Abstract: The present invention relates to a silicon-controlled rectifier (SCR) dimming circuit and method for regulating the luminance of a light-emitting diode (LED) load. In one embodiment, an SCR dimming circuit can include: an SCR rectifying circuit having an SCR element that receives an AC power supply, and generates a lack-phase AC voltage; a rectifier bridge that converts the lack-phase AC voltage to a lack-phase DC voltage, where the lack-phase DC voltage is filtered through a filter capacitor to generate a smooth DC voltage; a conduction phase angle signal generator that receives the lack-phase DC voltage and generates a controlling signal indicating a conduction phase angle range of the SCR element; and a dimming signal generator that compares the controlling signal and a slope reference signal to output a dimming signal to control the luminance of the LED load.

Abstract: The present invention provides a pair of input terminals to which AC voltage is input, the AC voltage being phase-controlled by a dimmer for phase-controlling AC voltage of an AC source; a damping circuit which has a resistor inserted to a position, into which input current flows from the AC source via the dimmer in series, and a capacitor and an inductor which form a closed circuit together with the AC source and the dimmer, and suppresses high-frequency vibration generated in the dimmer when a phase control element of the dimmer is turned on; and an LED lighting circuit which rectifies AC voltage phase-controlled and input via the pair of input terminals, converts DC output voltage, which is obtained by rectification, so that the voltage adapts to a load, and lights the LED.