Abstract: A load control device for controlling the amount of power delivered from an AC power source to an electrical load is operable to conduct enough current through a thyristor of a connected dimmer switch to exceed rated latching and holding currents of the thyristor. The load control device comprises a controllable-load circuit operable to conduct a controllable-load current through the thyristor of the dimmer switch. The load control device disables the controllable-load circuit when the phase-control voltage received from the dimmer switch is a reverse phase-control waveform. When the phase-control voltage received from the dimmer switch is a forward phase-control waveform, the load control device is operable to decrease the magnitude of the controllable-load current so as to conduct only enough current as is required in order to exceed rated latching and holding currents of the thyristor.

Abstract: A direct drive LED lighting circuit includes a LED current control circuit with a power switching device; a current sensing device, an averaging circuit, and an error amplifier. A LED chain circuit is formed by connecting several LEDs in series with a capacitor connecting in parallel with the series of LEDs, with a current flowing in side as a positive terminal, and a current leaving terminal as a negative terminal. The LED chain circuit and the LED current control circuit are connecting in series and the whole circuit is connected between the positive and negative terminals of a rectified AC power source.

Abstract: A device suppresses flicker and improves compatibility of a lamp including at least one solid state light source, the lamp being operably connected to a control circuit, such as a dimmer circuit. The device includes a connector enabling connection of the solid state light source to a lamp socket configured to receive an incandescent light source, and an adapter circuit connected in parallel with the at least one solid state light source when the solid state light source is connected to the socket via the connector. The adapter circuit provides a resistive path for current to pass through the lamp, during all or part of the AC mains cycle.

Abstract: A power supply includes a power converter configured to convert an input voltage to a target output DC voltage in response to a feedback signal, the feedback signal having a value. The power supply also includes a regulator coupled to the power converter and configured to generate an output power status signal, which may be in one of two states depending whether an output current from the regulator is above or below a target current over a preset time duration. Further, a control circuit is coupled to the power converter and to the regulator and configured to increment or decrement the value of the feedback signal depending on the state of the power status signal.

Abstract: An LED light including: a light-emitting bulb including a shell; a lamp holder connected to the light-emitting bulb and including external thread; a power driver disposed in the lamp holder; a stem including a wire; and a light-emitting component. The stem and the light-emitting component are disposed in the shell. One end of the stem is connected to the power driver, and the other end of the stem is connected to the light-emitting component. The light-emitting component includes at least two bar-type LED filaments. The at least two bar-type LED filaments are connected in series or in a combination of series and parallel connections. The at least two bar-type LED filaments are connected to the power driver through the wire of the stem.

Abstract: The present invention relates to an illumination control method and system for LED lamps, where the system comprises: a receiver module (1) configured to obtain a number of illumination levels (N) indicative of the light resolution of a LED lamp (6) and a duty cycle (D) associated with a desired light intensity for a LED lamp (6), a control module (2) comprising a control unit (7) configured to: generate a periodic signal with a period (T) and a duty cycle from the number of illumination levels (N) and the duty cycle (D), generate an illumination control signal (SCi) from the periodic signal for controlling the power supply of at least one LED lamp (6), and a power supply module (3) configured to power at least one LED lamp (6) according to the illumination control signal (SCi).

Abstract: A light source device includes: an excitation light source unit that emits excitation light; a phosphor wheel unit that includes a wheel that produces fluorescence by the excitation light and that, by causing the wheel to rotate, changes the position on the wheel that is irradiated by the excitation light; a detection unit that detects rotation of the wheel; and a control unit that changes intensity of the excitation light on the basis of the detection result of the detection unit and the fluorescence characteristic of the wheel.

Abstract: A lighting control system includes a sensor to generate a signal representative of at least one of a position of a seat, a presence of passenger in the seat, the position of at least one hand of the passenger, a configuration of the at least one hand of the passenger, and a direction of movement of the at least one hand of the passenger. A first light source, which generates a first light column, is located forward of the seat. A second light source, which generates a second light column, is located rearward of the seat. A controller generates a control signal that controls at least one parameter associated with an intensity, a color, a projected pattern, projected pattern location, or a width formed by a combination of the first and second light columns.

Abstract: A light driving circuit includes a first and second illuminant unit, a power conversion unit, a first and second switching unit, and a first control unit. The power conversion unit receives an input voltage and converts the input voltage into an output voltage. The first switching unit is coupled to the first illuminant unit. When the first switching unit is turned on, the first illuminant unit is driven by the output voltage to emit light and generate a first output current. The second switching unit is coupled to the second illuminant unit. When the second switching unit is turned on, the second illuminant unit is driven by the output voltage to emit light and generate a second output current. The first control unit controls the first switching unit and the second switching unit to be turned on/off according to the first output current and the second current, respectively.

Abstract: A lighting device includes a power converter and a controller. The power converter includes a transformer having primary, secondary and tertiary windings, and a switching device electrically connected in series with the primary winding. The controller is configured to measure a signal simulating a primary current flowing through the primary winding based on a voltage occurring across the tertiary winding and detect timing for turning the switching device off based on the signal simulating the primary current.

Abstract: Embodiments of an amplifier for a constant-current light-emitting diode (LED) driver circuit and a constant-current LED driver integrated circuit (IC) device having the amplifier are described. In one embodiment, an amplifier includes a folded cascode input stage including chopping switch circuits configured to perform frequency chopping to reduce an input offset of the amplifier and a rail-to-rail output stage connected to the folded cascode input stage. The rail-to-rail output stage includes slew rate enhancement circuits.

Abstract: An emergency lighting driver (100, 200, 400) includes: a power translation circuit (120, 220, 421/423/425) which receives input power from an emergency power source (10) and supplies output power to a load (20); and a programmable control device (140, 240) which controls the power translation circuit in response to a voltage feedback signal and a current feedback signal to cause the output power supplied to the load to have a programmed power output profile (302, 304), wherein the programmed power output profile is a function of time, temperature, the type of energy source employed for the emergency power source, the amount of remaining energy stored in the emergency power source, and/or the occupancy of an area in which the emergency lighting driver is located.

Abstract: The invention describes a driver arrangement (1) for driving a semiconductor lighting load (2), which driver arrangement (1) comprises a first power converter (10) arranged to drive a portion (2_10, 2_10_11) of the lighting load (2); a second power converter (11) arranged to drive a portion (2_11, 2_10_11) of the lighting load (2); a monitoring arrangement (12) realized to monitor an operating characteristic (12A, 12B, 12C, IR3O) ° f the second power converter (11); and a control signal generator (13) for generating a control signal (130, Vshunt) for the first power converter (10) on the basis of the monitored operating characteristic (12A, 12B, 12C, IR3O). The invention also describes a lighting arrangement (100), which lighting arrangement (100) comprises a semiconductor lighting load (2); and such a driver arrangement (1) for driving the semiconductor lighting load (2). The invention also describes a method of driving a semiconductor lighting load (2).

Abstract: A lighting system includes: an illumination light source which irradiates a user with illumination light; a user interface which receives a user operation; a controller which controls an amount of light of the illumination light source and an irradiation period of the illumination light source; and a storage which stores characteristic information having a negative correlation between the amount of light and the irradiation period. When the user interface receives a user operation which specifies a value of one of the amount of light and the irradiation period, the controller determines a value of the other according to the characteristic information and controls the illumination light source according to the specified value of the one of the amount of light and the irradiation period and the determined value of the other.

Abstract: Disclosed are LED controllers for dimming. An LED controller includes a current driver, a pulse-width modulator, a feedback circuit, and a decoupling circuit. The current driver, selectively in response to a dimming signal, causes a driving current flowing through one LED string. The dimming signal is capable of defining a dimming ON period and a dimming OFF period. The pulse-width modulator generates a PWM signal to control a power switch, in order to buildup a driving voltage at a power node of the LED string. The PWM signal is generated in response to a compensation signal. The feedback circuit, based upon a feedback voltage from the light emitting device, drives a compensation capacitor to generate the compensation signal. The decoupling circuit defines a decoupling period at the start of the dimming ON period and causes the feedback circuit not driving the capacitor during the decoupling period.

Abstract: Method for the operation and the expansion of a network of lights, each light in the network including a control module which is assigned to a group, each control module being in communication with a group controller as well as control modules in the same group. The network can be expanded by installing (19) new lights with their associated control modules, and each new control module scans (20) its environment and transmits environmental information to a central server where the environmental information is analyzed and the new control modules are allocated (21) into groups. After allocation to a group in which control modules may be moved from one group to another or a new group is formed, the new control modules are available for normal operation. This process is repeated for each new light and associated control module.

Abstract: Intelligent illumination device are disclosed that use components in an LED light to perform one or more of a Wide variety of desirable lighting functions for very low cost. The LEDs that produce light can be periodically turned off momentarily, for example, for a duration that the human eye cannot perceive, in order for the light to receive commands optically. The optically transmitted commands can be sent to the light, for example, using a remove control device. The illumination device can use the LEDs that are currently off to receive the data and then configure the light accordingly, or to measure light. Such light can be ambient light for a photosensor function, or light from other LEDs in the illumination device to adjust the color mix.

Abstract: An LED lighting device using a ballast may be provided that includes: an LED unit which includes at least one LED device; a rectifier which rectifies a current power signal output from the ballast; and a current driving unit which receives an output current of the rectifier and controls the power which is transmitted from the ballast to the LED unit. The current driving unit transmits current which has a magnitude greater than that of the output current of the rectifier to the LED unit.

Abstract: An LED driver circuit capable of overcoming the issues in that a brightness change is perceived as a stepped change in a very low light amount region or light abruptly goes out by using PWM control and of realizing smooth dimming even at a very low amount of light is provided. In the LED driver circuit, a first circuit including a first resistor and a first power transistor connected in series and a second circuit including a second resistor and a second power transistor connected in series are connected in parallel with each other and are connected to an LED. First and second PWM signal generator circuits drive the first and second power transistors, respectively. When the first and second power transistors are in an on-state, currents flow through the LED via the first and second resistors, respectively, which enable a smooth brightness change even in a low illuminance region.

Abstract: A power circuit for an LED lighting device including an alternative current (AC) power supply, a dimmer, a transformer and a dimming control circuit. The dimming control circuit includes a filtering unit configured to filter a voltage signal outputted from the transformer and a rectifying unit configured to receive the signal outputted from the filtering unit and rectify the signal to a DC signal. The dimming control circuit also includes a boost converter unit configured to boost the received DC voltage to a needed DC voltage and a voltage feedback control circuit unit configured to control the DC voltage boosted by the boost converter unit. Further, the dimming control circuit includes a buck converter unit configured to convert the boosted DC voltage to the voltage and current needed by the LED lighting device and a digital control unit configured to automatically adjust current strength needed by the buck converter unit.