Abstract: A power converter circuit may include a control circuit configured to generate a drive signal for rendering a semiconductor switch conductive and non-conductive to generate a bus voltage across a bus capacitor. The control circuit may adjust a minimum operating period of the drive signal to a first value when an output power of the power converter circuit is greater than a first threshold and to a second value when the output power is less than a second threshold. The control circuit may comprise a comparator that generates the drive signal in response to a sense voltage and a threshold voltage. When operating in a standby mode, the control circuit may adjust a magnitude of the threshold voltage based on an instantaneous magnitude of an alternating-current line voltage received by the power converter circuit, such that an input current drawn by the power converter circuit is sinusoidal.

Abstract: A pulse arc welding device is controlled so as to alternately repeat a peak current period in which a welding current is a peak current and a base current period in which the welding current is a base current smaller than the peak current, feed a welding wire to an object at a feeding speed while the welding current flows through the welding wire, generate an arc between the welding wire and the object, and weld the object. So as to keep an arc length of the arc to be constant, in the base current period, the feeding speed is set to a first feeding speed and, in the peak current period, the feeding speed is set to a second feeding speed which is larger than the first feeding speed and corresponds to the first feeding speed. By this method, good welding quality with reduced spattering and suppressed undercut can be obtained.

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: An air conditioner current loop communication circuit includes an indoor unit current loop communication circuit and an outdoor unit current loop communication circuit connected to each other via a communication connection wire and an AC power connection wire to form a current loop communication loop, an indoor microcontroller unit (MCU) and an outdoor MCU configured to communicate with each other through the current loop communication loop, and a switching power supply circuit connected in series to the communication connection wire or the AC power connection wire and configured to output a DC power to the current loop communication loop.

Abstract: An electronic switch control circuit for a solar lighting system and a method for controlling the same. Solar panels of the solar lighting system are respectively coupled to a charging circuit and a photoelectric signal identification circuit which is coupled to a logic control circuit and an enable circuit sequentially. The enable circuit is respectively coupled to a driving circuit and the charging circuit. The photoelectric signal identification circuit, the logic control circuit, the enable circuit and the charging circuit are respectively coupled to the common end of the driving circuit and rechargeable batteries. The electronic switch control circuit further includes a timing circuit and an oscillating circuit, wherein the oscillation circuit is coupled to the timing circuit, and the timing circuit is coupled to the logic circuit. The oscillation circuit and the timing circuit are coupled to the common end of the rechargeable batteries and the driving circuit.

Abstract: A shift register unit, a gate driving circuit, a display device, and a driving method are disclosed. The shift register unit includes a first sub-unit and a leakage prevention circuit; the first sub-unit includes a first input circuit and a first output circuit. The first input circuit controls a level of a first node in response to a first input signal, the first output circuit provides an output signal at an output terminal under control of the level of the first node, the leakage prevention circuit is connected to the first node and a first voltage terminal, and controls a level of a leakage prevention node under control of the level of the first node, whereby a conductive path is formed between the leakage prevention node and the first voltage terminal, and a circuit connected between the first node and the leakage prevention node is turned off.

Abstract: A load control system includes a load control device and a remote control for configuring and controlling operation of the load control device. The load control device and remote control may be mounted to an electrical wallbox. The system may be configured by associating the remote control with the load control device, and actuating a button on the remote control to configure the load control device. A second remote control device may be directly or indirectly associated with the load control device. The load control device and remote control may communicate via inductive coils that are magnetically coupled together. The remote control may be operable to charge a battery from energy derived from the magnetic coupling between the inductive coils. The load control device and remote control may include near-field communication modules that are operable to communicate wirelessly via near-field radiation.

Abstract: Light emitting diode (LED) lighting fixtures are presented that use a low-pass filter to smooth out or eliminate discrete, step changes in LED light fixture brightness, that may result from the use of digital brightness level settings. Because some lighting applications require a fast response to changes in the set brightness level, and some applications require a slower response, one set of examples use a switchable RC low-pass filter circuit, with two or more selectable RC time constant values. Another set of examples use a programmable resistance integrated circuit to achieve a more continuously-variable time constant, for greater flexibility in adjusting the response time of the LED lighting fixture, in response to user brightness inputs. The user is able to control the maximum rate of change of the LED light fixture's brightness, in response to changes in the brightness setting.

Abstract: The present disclosure provides an intelligent lighting control system. The lighting control system includes a base module including a base housing forming a well and including a first electrical connector positioned in the well. A depressible switch is housed in the well that includes a spring biasing the depressible switch into an extended position that opens an electrical circuit between the power terminal and the first electrical connector. The lighting control system also includes a light switch module configured for nesting, at least in part, in the well of the base module. The light switch module includes a module housing configured to press the depressible switch into a retracted position upon nesting in the well and thereby close the electrical circuit between the power terminal and the first electrical connector and release the depressible switch into the extended position when unnested from the well of the base module.

Abstract: The auxiliary outlet system is an electrical socket that is configured for use with a national electric grid. The auxiliary outlet system is a port that distributes electricity from the national electric grid. The auxiliary outlet system comprises a transmitting outlet and one or more mirrored outlets. The transmitting outlet is configured to distribute electricity from the national electric grid. The one or more mirrored outlets are configured to distribute electricity from the national electric grid. The transmitting outlet broadcasts a radio frequency signal to each of the one or more mirrored outlets. The one or more mirrored outlets mirror the operation of the transmitting outlet. Specifically: a) each of the one or more mirrored outlets are enabled to distribute electricity when the transmitting outlet is enabled to distribute electricity; and, b) each of the one or more mirrored outlets are de-energized when the transmitting outlet is de-energized.

Abstract: A table that includes a planar upper surface having a recess, a lamp positioned in the recess, a first sensor, and an embedded touch control. The lamp can be in a closed position or an open position, and have a first section and a second section. The first section is attached to the planar upper surface at a proximal end thereof. The first sensor detects the position of the lamp and communicates with circuitry to activate and deactivate lamp based on the position of the lamp. The embedded touch control is located beneath the planar upper surface and controls the light level of the lamp.

Abstract: An automated dimming load controller automatically measures the relationship between the current draw and the dimmer setting for each light or group of lights connected to the load controller. Once measured, the relationship between the current draw and the dimmer setting can be used to enable the dimmer controller to adjust the lights between their minimum and maximum effective illumination. This automatic setting of the dimmer controller may be performed regularly to accommodate changes in performance or replacement of any of the connected lights, drivers or ballasts.

Abstract: A lighting wall controller having a capability to reject user inputs at a surface of the wall controller and/or proximity detection in accordance with sensing signals received at locations on and near the wall controller. Programming configures a processor for proximity detection to detect a presence of a conductive object within a predetermined distance to the wall controller. The processor further determines whether user inputs correspond to touches at locations on the wall controller or user gestures near the wall controller to perform one of a plurality of defined lighting functions for a lighting system. When user inputs do not correspond to defined lighting functions, a number of the non-defined inputs is counted to provide an indicator of activity on the surface of the wall controller to activate a locked mode for a duration of the non-defined inputs.

Abstract: An LED circuit with color temperature adjustment comprises a first LED string, a resistor, and a second LED string. The first LED string has a first color temperature. The resistor is connected in series with the first string. The second LED string has a second color temperature. The first LED string is connected in parallel with the second LED string. The second color temperature is higher than the first color temperature. The integrated color temperature of the first LED string and the second LED string increases when the total current of the first LED string and the second LED string increases. The present disclosure not only can provide an LED circuit with color temperature adjustment, but also can provide an LED circuit which can adjust the color temperature by the combinations of the LED strings connected in parallel or series.

Abstract: An apparatus for controlling an EL drive voltage for a display panel is disclosed, which includes a current sensing circuit configured to detect an EL drive current signal outputted to the display panel, and convert the EL drive current signal into a first voltage signal, a signal generation circuit configured to generate a pulse signal based on the first voltage signal, a current protection circuit configured to generate a first control signal based on the first voltage signal and a reference voltage, and a signal coupling circuit configured to output, based on the first control signal, the pulse signal or a low level signal as a second control signal to control the EL drive voltage. According to the embodiments of the present disclosure, the EL drive voltage of the display panel can be dynamically controlled, and be reset to normal when it is overhigh.

Abstract: System and method for controlling one or more light emitting diodes. For example, the system includes a bleeder configured to receive a rectified voltage generated by a rectifying bridge, and a dimmer detector configured to receive an input voltage generated by a voltage divider, determine whether or not the rectified voltage is associated with a TRIAC dimmer, and output a control signal to the bleeder. The voltage divider is configured to receive the rectified voltage, and the input voltage indicates a magnitude of the rectified voltage.

Abstract: Embodiments of the present disclosure relate to an emergency inverter and an emergency lighting system. The emergency inverter comprises a power detecting module and a dimming signal generating module. The power detecting module is configured to detect an output power of the emergency inverter in an emergency state. The dimming signal generating module is coupled to the power detection module and configured to generate a dimming signal based on the output power of the emergency inverter in the emergency state.

Abstract: A device and method are disclosed for optimizing self-power consumption. The device may sense one or more operating conditions of the device. The device may further select one or more operating parameters associated with at least one of the one or more operating conditions. The device may also estimate a power consumption associated with executing an algorithm to generate at least one updated value for at least one of the one or more operating parameters as well as estimate a power savings associated with operating using the updated value. The device may compare the estimated power consumption to the estimated power savings and determine whether to execute the algorithm based on the comparing.

Abstract: A sleep system is provided comprising a head support section, a torso support section, a leg support section, and a cradle surface provided on at least an upper portion of the torso support section. The head support section is generally laterally angled at an angle greater than the lateral angle of the torso support section and the leg support section. The cradle surface has at least a partial curvature and a lateral width of from about 12 inches to about 36 inches. The lateral angle of the head support section is at least about 10 degrees, the lateral angle of the torso support section is greater than the lateral angle of the leg support section, and the lateral angle of the leg support section is less than about 10 degrees.

Abstract: A method for controlling an output of an electrical AC voltage U comprising the following steps: switching on a current flow I induced by the AC voltage as soon as an absolute value of the AC voltage U exceeds a switching-off target voltage, and switching on the current flow I as soon as the absolute value for the AC voltage U falls below a switching on target voltage. The switching-off target voltage and the switching-on target voltage are defined as positive and the switching-on target voltage is lower than or equal to the switching-off target voltage. The method according to the invention serves to dim an LED lamp in a brightness range of 0% to 100% of a maximum brightness of the LED lamp.

Abstract: An electromotive furniture drive includes an adjusting drive for electromotive movement of a movable furniture component relative to another furniture component, a remote control, a communication unit which is configured to receive a wireless signal from the remote control and to determine a signal strength of the wireless signal, and a control device which is configured to control operation of the adjusting drive in response to the wireless signal only when the signal strength of the wireless signal exceeds a predetermined threshold value.

Abstract: An electrical connecting system configured to electrically connect a plurality of lighting fixtures, wiring harness, and method are presently disclosed. The electrical connecting system has a first wiring harness configured to electrically connect with a sole external power supply and a first lighting fixture and a second wiring harness configured to electrically connect with a second lighting fixture and the first wiring harness. The electrical connecting system is configured to supply power to each lamp, in the plurality of lighting fixtures, with the sole external power supply.

Abstract: An apparatus can include: a bleeder circuit coupled to a DC bus of an LED driver having a silicon-controlled dimmer, where the bleeder circuit is controlled to discharge a current of the DC bus; a controller configured to control the bleeder circuit to discharge the DC bus at a first current after detecting a transition in a voltage of the DC bus; and the controller being configured to control the bleeder circuit to discharge the DC bus at a second current until the DC bus voltage rises to a predetermined load driving voltage, where the second current is less than the first current.

Abstract: System for determining periodic values of phase angle ? of waveform power input including voltage detector for detecting periodic values of average voltage of waveform power input and detecting corresponding periodic values of peak voltage of waveform power input. System also includes phase angle ? detector in signal communication for receiving periodic values of average voltage and peak voltage from voltage detector. Phase angle ? detector also detects periodic values each being ratio of one of periodic values of average voltage divided by corresponding periodic value of peak voltage, or being ratio of peak voltage divided by average voltage; and determines periodic values of phase angle ? of waveform power input corresponding to periodic values of ratio. Lighting systems.

Abstract: Provided are an input voltage detection circuit and a power supply including the same. The power supply includes a rectifier circuit configured to generate a line input voltage by rectifying an alternating current (AC) input. The input voltage detection circuit which is applied to the power supply generates a peak sensing voltage that indicates a predetermined peak area defined around a peak of the line input voltage, generates a peak detection signal that indicates the peak of the line input voltage based on a center of the peak sensing voltage, and generates an input sensing voltage corresponding to the line input voltage by being synchronized with the peak detection signal. The power supply may control a switching period according to the input sensing voltage.

Abstract: Provided is a signal isolator with reduced power loss. The signal isolating circuit comprises an input stage and an output circuit that is connected downstream thereof and which includes a linear regulator. The linear regulator comprises an operational amplifier and a switching regulator, wherein an input of the switching regulator is connected to an output of the operational amplifier and an output of the switching regulator is fed back to a first input of the operational amplifier. The operational amplifier regulates the switching regulator such that the switching regulator provides at its output an output measuring signal for a load that corresponds to the input measuring signal.

Abstract: A luminaire includes: a light-emitting module; a base having a front surface on which the light-emitting module is disposed; a cover which is translucent and covers the light-emitting module; a controller which is disposed on a back surface of the base and controls the light-emitting module; a first antenna which transmits and receives a first polarized wave; and a control wire which connects the controller and the first antenna. The control wire includes an exposed portion which is a portion of the control wire in a longitudinal direction of the control wire and which is disposed between the base and the cover to transmit and receive a second polarized wave that differs from the first polarized wave in a polarization direction.

Abstract: A light-emitting diode driving module includes an LED driving circuit to activate light-emitting diodes driven by a rectified voltage, and to adjust driving current conducted through driving nodes to the light-emitting diodes depending on a voltage of a driving current setting node; and a driving current controller to control the voltage of the driving current setting node by outputting a driving current control signal. The driving current controller includes a control signal output circuit connected to a dimming node to receive a dimming signal when the rectified voltage is modulated, and to adjust the driving current control signal depending on the dimming signal; a mode detector to detect whether the rectified voltage is modulated by receiving a source voltage depending on the rectified voltage, and to enable a selection signal depending on a detection result; and a power compensator to adjust the driving current control signal when the selection signal is enabled.

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 power drawing device using a single live wire includes a first and second mechanical switches, and a power drawing circuit, wherein the first mechanical switch includes a first contact connected to a live wire, a third contact connected to a first light adjusting circuit, and a fifth contact connected to the first light adjusting circuit; the second mechanical switch includes a first contact connected to the live wire, a third contact connected to a second light adjusting circuit, a fifth contact connected to the second light adjusting circuit, and a sixth contact connected to the first mechanical switch; and the power drawing circuit includes a first terminal connected to the live wire, a second terminal connected to the second mechanical switch, a third terminal connected to the first light adjusting circuit, and a fourth terminal connected to the second light adjusting circuit.

Abstract: A dimmable ballast circuit for a compact fluorescent lamp controls the intensity of a lamp tube in response to a phase-control voltage received from a dimmer switch. The ballast circuit comprises a phase-control-to-DC converter circuit that receives the phase-control voltage, which is characterized by a duty cycle defining a target intensity of the lamp tube, and generates a DC voltage representative of the duty cycle of the phase-control voltage. Changes in the duty cycle of the phase-control voltage that are below a threshold amount are filtered out by the converter circuit, while intentional changes in the duty cycle of the phase-control voltage are reflected in changes in the target intensity level and thereby the intensity level of the lamp tube.

Abstract: A system and method control an amount of power delivered by a power converter (220) to a solid state lighting load (240). It is determined whether a dimmer (204) is present between a voltage source (201) and the power converter (220) based on a rectified input voltage from the voltage source. When the dimmer is determined to be present, an operating point of the power converter is adjusted to increase the amount of power delivered by the power converter to the solid state lighting load by a compensation amount, so that the increased amount of power is equal to an amount of power delivered by the power converter when the dimmer is not present.

Abstract: In some examples, a method of controlling a first switch and a second switch of a resonant mode power converter circuit, the method comprising delivering control signals to the first switch and the second switch at a switching frequency. The method also comprises determining, for a first driving period, a first phase relation between a phase of a resonant current in the resonant mode power converter circuit and a phase of the control signals. The method further comprises determining, for a second driving period, a second phase relation between a phase of the resonant current and a phase of the control signals, and controlling the switching frequency based on a difference of the first phase relation and the second phase relation.

Abstract: A controller for use in a power converter includes a current sense circuit to generate a current limit signal and an overcurrent signal in response to a source signal, a first sense finger signal, and a second sense finger signal. A control circuit is coupled to generate a control signal in response to the current limit signal and the overcurrent limit signal. A drive circuit is coupled to generate a drive signal with a multiple stage gate drive in response to the control signal. The drive signal in a first stage of the multiple stage gate drive is a weak turn on drive signal to turn a switch on slowly to reduce electromagnetic interference (EMI). The drive signal in a second stage of the multiple stage gate drive is a strong turn on drive signal to fully turn on the switch quickly to enable accurate current sensing of the switch.

Abstract: Embodiments related to efficiently constructing an augmented reality environment with global illumination effects are disclosed. For example, one disclosed embodiment provides a method of displaying an augmented reality image via a display device. The method includes receiving image data, the image data capturing an image of a local environment of the display device, and identifying a physical feature of the local environment via the image data. The method further includes constructing an augmented reality image of a virtual structure for display over the physical feature in spatial registration with the physical feature from a viewpoint of a user, the augmented reality image comprising a plurality of modular virtual structure segments arranged in adjacent locations to form the virtual structure feature, each modular virtual structure segment comprising a pre-computed global illumination effect, and outputting the augmented reality image to the display device.

Abstract: A dimming module and a solid state lighting device are shown. The dimming module includes a rectifying circuit, a phase control circuit, a processing circuit and a first driving circuit. The rectifying circuit is configured to convert an input AC voltage to a rectified voltage signal. The phase control circuit is configured to receive the rectified voltage signal and a dimming command, and output a control voltage signal correspondingly in which the phase control circuit controls a phase delay angle of the control voltage signal according to the dimming command. The processing circuit is configured to receive the control voltage signal and adjust a first driving voltage signal according to the phase delay angle. The first driving circuit is configured to receive the first driving voltage signal to drive a first lighting module.

Abstract: A dimming control method and circuit thereof are provided. After receiving a TRIAC signal with at least one positive/negative half cycle waveforms, the turning points of the positive/negative half cycles are detected to obtain the conduction angles of the positive/negative half cycle waveforms. Then, a pulse width modulated signal with the symmetrical positive and negative half cycle waveforms is rebuilt to control a lamp. Therefore, the disclosure can solve the flickering issue of the lamp.

Abstract: According to one aspect, embodiments of the invention provide an uninterruptible power supply (UPS) system comprising an input configured to receive input AC power, an output configured to provide output AC power to a load, a DC power source coupled to a DC bus, an inverter having an input coupled to the DC bus and an output coupled to the output of the UPS system, the inverter configured to receive DC power at the input from the DC bus and provide AC power having a voltage to the output, and a controller coupled to the output of the inverter and configured to operate the inverter based on an average voltage of the AC power at the output of the inverter.

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 comprising two MOS-gated transistors, and a control circuit. The control circuit generates first and second drive voltages for individually controlling the MOS-gated transistors, and controls the gate coupling circuit to cause the MOS-gated transistors to conduct a pulse of current through a gate terminal of the thyristor to render the thyristor conductive at a firing time during a present half cycle of the AC power source, and to allow the MOS-gated transistors to conduct at least one other pulse of current through the gate terminal after the firing time during the present half cycle.

Abstract: Disclosed is a line voltage compensation AC LED driving device. The line voltage compensation AC LED driving device comprises a line voltage compensation module and an AC LED driving module. The line voltage compensation module detects an output voltage of a rectifier bridge, and outputs a corresponding line voltage compensation reference voltage to the AC LED driving module according to the change of the output voltage of the rectifier bridge, and the AC LED driving module adjusts a driving current in real time according to the line voltage compensation reference voltage to keep the output power unchanged.

Abstract: A light unit includes a DC/DC converter. A plurality of unit light emitting diode columns receive a voltage applied from the DC/DC converter. A plurality of transistors, respectively, are connected to the plurality of unit light emitting diode columns. A current deviation compensating unit compensates for deviations between currents respectively flowing through the plurality of unit light emitting diode columns by a pulse current width modulation average current control method. A connection switch sequentially connects the current deviation compensating unit with the plurality of transistors. A resistor is connected to output terminals of the plurality of transistors. A switch controller controls connection between the connection switch and the current deviation compensating unit based on a signal applied to the resistor.

Abstract: In one aspect, an integrated circuit (IC) is configured to receive an input signal and includes a boost duty cycle control circuit configured to provide duty cycle control to a power conversion stage configured to drive a load. The power conversion stage is configured to receive an input voltage. The IC also includes a current control circuit configured to control current of a first current source coupled to the first load and an inverter configured to provide an output signal comprising a negative of the input voltage, the output of the inverter configured to be coupled to the boost duty cycle control circuit.

Abstract: A circuit and method for controlling one or more light emitting diodes (LEDs) includes one or more LEDs connected to the emitter a transistor and controlling the brightness of the LEDs over a large range based on a voltage range at a base of the transistor controlled by an automatic adjusting mechanism.

Abstract: An apparatus is adapted to drive an insulating gate-type semiconductor element by a first control voltage and a second control voltage, that are supplied to a first insulating gate and a second insulating gate, respectively, and includes a first noise filter inputting a signal about current that passes through the insulating gate-type semiconductor element, a first comparator making a comparison between an output signal of the first noise filter and a first reference signal and outputting a first comparison result, a first control voltage output circuit, and a second control voltage output circuit, the second control voltage output circuit being adapted to reduce the second control voltage when it is determined from the first comparison result that overcurrent passes through the insulating gate-type semiconductor element, the first control voltage output circuit being adapted to reduce the first control voltage after the second control voltage is reduced.

Abstract: A dimming lampholder includes a printed circuit board installed in the dimming lampholder, a switch and a dimming circuit installed in dimming lampholder and operated together with a dimmable energy-saving fluorescent bulb and a dimmable LED bulb. The dimmable energy-saving fluorescent bulb and the dimmable LED bulb may be installed and used directly to achieve the effect of adjusting the brightness of the emitting light.

Abstract: A pulse-transformer-based isolated gate driver circuit uses a small count of high-temperature-qualified components to drive a power semiconductor switch with asymmetrical voltage biases. A differential driver generates a pulse signal from a pulse-width-modulated signal, which is passed to a charge and lock circuit through a transformer. The charge and lock circuit includes an activation path and a deactivation path, which are selectively open to current flow based on positive or negative voltage pulses in the pulse signal, to selectively turn the main semiconductor switch on or off. The charge and lock circuit can lock voltage across the main semiconductor switch to keep the main semiconductor switch in an “on” or and “off” state.

Abstract: A pulse-transformer-based isolated gate driver circuit uses a small count of high-temperature-qualified components to drive a power semiconductor switch with asymmetrical voltage biases. A differential driver generates a pulse signal from a pulse-width-modulated signal, which is passed to a charge and lock circuit through a transformer. The charge and lock circuit includes an activation path and a deactivation path, which are selectively open to current flow based on positive or negative voltage pulses in the pulse signal, to selectively turn the main semiconductor switch on or off. The charge and lock circuit can lock voltage across the main semiconductor switch to keep the main semiconductor switch in an “on” or and “off” state.

Abstract: An LED driver is provided with input surge absorbing capacity. A surge protection circuit branch is coupled across output lines from a DC power source, in parallel with and between a filtering capacitor and a non-isolated buck-boost PFC circuit. A variable impedance device such as a spark gap is coupled to a first power line and having a breakdown voltage to operate as an open circuit during normal operating conditions with respect to a peak input voltage across the capacitor. Responsive to a surge condition with respect to excess energy across the capacitor, the spark gap operates as a closed circuit, and a second capacitor coupled between the spark gap and the second line absorbs the excess energy. Responsive to a return to normal operating conditions, the spark gap reverts to an open state and the accumulated surge energy is discharged from the second capacitor to circuit ground.

Abstract: The present invention relates to a dimming control device and method, and a dimming control device according to an embodiment of the present invention may control the ON/OFF of a lamp depending on whether a power pad is touched, and control the brightness of the lamp depending on whether dimming pads are touched. Thus, a user may control brightness step by step and may conveniently manipulate each step of brightness.

Abstract: A digital dimmable driver system includes an alternating current input, a dimmer operable to perform a phase cut operation on a waveform from the alternating current input, a driver circuit operable to switch from a dimming mode to a universal voltage input mode based on a phase angle of the dimmer, and a power output operable to power a light.