Abstract: A driver for driving a load unit includes a conversion circuit, a bypass circuit and control circuit. The conversion circuit is configured for converting an input voltage into an output voltage, in which the load unit is coupled to the conversion circuit to receive the output voltage and an output current. The bypass circuit is electrically coupled to the conversion circuit and the load unit. The control circuit controls the output current to flow through the load unit to drive the load unit in a driving mode. The control circuit controls the output current to flow through the bypass circuit in a standby mode, in which the output current in the standby mode is lower than the output current in the driving mode.

Abstract: A LED quick activation system includes a driving circuit, a loading module, a filter capacitor, a current control switch, a quick discharging module and a primary controller. The primary controller records a preceding discharging parameter that the filter capacitor requires to discharge its cross voltage from a target charging voltage to the loading module's LED unit's barrier voltage. The primary controller calculates an equivalent charging period of charging the filter capacitor's cross voltage to the target charging voltage using the discharging parameter. The primary controller controls the current control switch to charge the filter capacitor and the loading module using the driving current of a charging amplitude during the equivalent charging period. The primary controller charges the filter capacitor and the loading module using the driving current of a regular amplitude after the equivalent charging period passes.

Abstract: A lighting fixture includes a light emitting diode (LED) light source, a clock module, and a controller configured to control one or more characteristics of a light emitted by the LED light source based on time information received from the clock module. The controller is further configured to determine a current time of a day from the time information received from the clock module.

Abstract: An LED driver circuit that can regulate the input signal voltage so that the driver circuit can be used over wide input voltage range or at predetermined voltages. Discrete components are used to drive an LED array with a constant current. The LED driver circuit includes a dynamic current regulator. The dynamic current regulator includes a resistor and capacitor in parallel to provide dynamic current regulation to a switching mode power supply circuit that controls the LED illumination.

Abstract: An illumination system verifies controls the operation of a luminaire without the use of any photometric data. The illumination system uses data indicative of a current time, date or latitude to determine one or more aspects of a solar event. Such aspects can include a scheduled, predicted or expected time of occurrence of the scheduled solar event. Responsive to the determination of a scheduled, predicted or expected time of occurrence of the scheduled solar event, a control subsystem can adjust the luminous output of a light source.

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: An apparatus for protecting a solid state retrofit lighting or illumination system from electrostatic discharge damage caused by charge induced onto conductive surfaces of the lighting or illumination system.

Abstract: Embodiments of the invention provided a driving circuit for powering a light-emitting diode (LED) light source. The driving circuit includes a rectifier, a filter capacitor, and a control circuit. The rectifier converts an AC voltage from an AC power source to a rectified AC voltage. The filter capacitor coupled to the rectifier filters the rectified AC voltage to provide a DC voltage. The control circuit controls power supplied to the LED light source. The control circuit enables a discharging current periodically to discharge the filter capacitor if a switch coupled between an AC power source and a rectifier is turned off and disables the discharging current if the control circuit determines that the switch is turned on.

Abstract: An apparatus for protecting a solid state retrofit lighting or illumination system from electrostatic discharge damage caused by charge induced onto conductive surfaces of the lighting or illumination system.

Abstract: Embodiments of the invention provided a driving circuit for powering a light-emitting diode (LED) light source. The driving circuit includes a rectifier, a s filter capacitor, and a control circuit. The rectifier converts an AC voltage from an AC power source to a rectified AC voltage. The filter capacitor coupled to the rectifier filters the rectified AC voltage to provide a DC voltage. The control circuit controls power supplied to the LED light source. The control circuit enables a discharging current periodically to discharge the filter capacitor if a switch coupled between an AC power source and a rectifier is turned off and disables the discharging current if the control circuit determines that the switch is turned on.

Abstract: A method of controlling an electronic ballast for a lighting circuit, the ballast including a bleeder, for use with dimmer circuits, by, in response to a mains supply being connected to the lighting circuit, determining whether a dimmer circuit is present in the lighting circuit; and in response to determining a dimmer circuit is not present, disconnecting the bleeder from the lighting circuit at least until the mains supply is disconnected. The method may be used during, and the determination of whether a dimmer circuit is present is stored at least until the mains supply is disconnected. Determination of either a leading or trailing edge phase cut dimmer may be made by looking for deviation from the expected sine-wave voltage, either directly through temporal or voltage deviation, or indirectly by examining the second differential of the voltage with respect to time.

Abstract: In at least one embodiment, a lighting system includes a link path power dissipation circuit to actively and selectively control power dissipation of excess energy in a switching power converter of the lighting system. The link path power dissipation circuit dissipates power through a link path of the switching power converter by controlling a link current of the switching power converter. In at least one embodiment, the controller controls the link path power dissipation circuit to limit the link current with a current source and dissipate power in the current source. In at least one embodiment, the link path power dissipation circuit includes a switch to limit the link current and dissipate power in the link path.

Abstract: An electronic ballast has control circuitry to provide a pre-heating signal to the filaments of a gas discharge lamp for a predetermined length of time before the lamp is ignited and, further, cease providing the pre-heating signal after the lamp has been ignited.

Abstract: A circuit for use with a power supply coupled in a switched leg of, for example, a lighting circuit, is described. The circuit provides a low impedance near the zero crossing of the AC signal and a high impedance thereafter, thereby allowing the power supply to draw current that bypasses, for instance, a light bulb.

Abstract: A protective device and a CCFL driving system using the same are provided. The protective device employs a short detecting circuit to receive a high AC power at the high terminal of the CCFL through a step-down capacitor. The protective device outputs a short-circuit protective signal during a shorting event. A rectified diode receives high AC power through the step-down capacitor, and outputs high DC power. A first charging capacitor couples with the rectified diode, and generates a detecting voltage in response to the high DC power. An open detecting circuit, having a threshold, couples with the first charging capacitor. The open detecting circuit outputs an open-circuit protective signal when the detecting voltage is over the threshold. The protective device of the present invention has a lighting voltage-limited circuit, which couples with the first charging capacitor. The lighting voltage-limited circuit receives the detecting voltage, and outputs an over-voltage protective signal.

Abstract: An adaptive compensation circuit for controlling a universal lamp driver coupled to a lamp is disclosed. The adaptive compensation circuit utilizes an identification of a lamp type of the lamp to thereby generate a signal indicative of a time constant of the lamp. The adaptive compensation circuit subsequently determines a zero position and a pair of pole positions corresponding to the time constant, and generates a control voltage in response to a determination of the zero position and the pair of pole positions. The control voltage facilitates an operation of the universal lamp driver to stably provide a lamp current to the lamp.

Abstract: A lighting circuit for a discharge lamp comprises a DC power supply circuit having a coil and a capacitor at its input stage, a DC-AC converter for converting the output voltage of the DC power supply circuit to an AC voltage and supplying the AC voltage to a discharge lamp, ignition means for generating an ignition pulse to the discharge lamp, and control means for performing variable control on the output voltage of the DC power supply circuit 3. The control means 6 performs such a boosting operation as to boost the output voltage of the DC power supply circuit 3 to a predetermined voltage under a loadless condition while the ignition pulse generated by the ignition means 5 is supplied to the discharge lamp 11 to thereby light the discharge lamp 11. During the boosting operation, the ignition means 5 applies the ignition pulse to the discharge lamp 11, lighting the discharge lamp.

Abstract: A protection circuit for non-isolated ballasts that drive gas discharge lamps to prevent shock hazards. The device acts to prevent excessive leakage currents from flowing between the ballast and ground by introducing a higher common mode impedance path in the circuit. A two stage common mode filter assembly has a first common mode inductor series connected to a second common mode inductor. A first capacitor is connected across the common mode inductors. A second capacitor is connected between the junction of the first capacitor, the first inductor, the second inductor and ground. The circuit protects by reducing high frequency leakage currents.

Abstract: The present invention includes an airfield lighting and control system for energizing at least one airfield control device and containing a ground fault detection system, comprising: (1) at least one airfield control device; (2) an AC electrical circuit conducting an AC signal and connected to said at least one airfield control device; (3) an inductive device, in electrical contact with said AC electrical circuit, which comprises (a) an inductive coil having an input pole and an output pole, and being loaded by a capacitor; (b) a driver winding for the inductive coil, the driver winding adapted to sense AC current flow through the inductor coil; (c) a sampling resistor connected to the driver winding and adapted to detect AC current in the form of a voltage across the sampling resistor; (d) signal processing circuitry comprising: (1) an inverting amplifier adapted to amplify the voltage; and (2) a phase shifter adapted to shift the phase of the voltage; and (e) a power amplifier connected to the signal proces