Abstract: A lamp driving device with an open voltage control comprises a DC power source, a square wave switch, a square wave controller, an LC resonant circuit, a driver transformer and a current detector; wherein the square wave switch outputs a square wave signal to the LC resonant circuit, the LC resonant circuit converts the square wave signal into a sinusoidal wave signal and outputs the sinusoidal wave signal to the driver transformer, and finally the driver transformer drives the lamp and the current detector is used to detect the operation of the lamp, and, if the lamp is found open-circuit, a PWM control pin will control the square wave controller to stop the operation of the lamp driving device, thereby enhancing safety in using the lamp.

Abstract: A light output control method for a lighting system is provided. The lighting system includes a plurality of sensors and a light-emitting unit. The light output control method includes steps of: sensing a motion of an object within the sensing ranges of the sensors at different time spots, thereby generating multiple sensing values; obtaining a sensing sequence data according to the sensing values indicating the motion of the object sensed by the sensors; controlling the light-emitting unit to perform a light output control operation if the sensing sequence data complies with a predetermined condition.

Abstract: A method for operating one or more plasma processes in a plasma chamber, with at least two power supplies, the method comprising the following process steps: a. carrying out an arc detection for at least one of the power supplies; b. generating at least one signal relating to the arc detection and/or data relating to the arc detection; transferring the at least one signal and/or the data to a plasma process-regulating device and/or to one or more other power supplies or to one or more of the arc diverter devices associated with the other power supplies.

Abstract: An electronic device includes circuitry for driving a light-emitting diode (LED) or other light-emitting semiconductor device.

Abstract: An LED device comprises an LED assembly and a power supply circuit. The power supply circuit includes an AC circuit connecting to the power source, a DC circuit coupling with the AC circuit, a driving circuit and a snubber circuit connected with each other and located between the DC circuit and the LED assembly. The locations of the driving circuit and the snubber circuit in the power supply circuit are exchangeable, i.e., the driving circuit being connected to the DC circuit and the snubber circuit being connected to the LED assembly, or the driving circuit being connected to the LED assembly and the snubber circuit being connected to the DC circuit. The snubber circuit is used for extending a time period for a voltage value of a DC initially applied to the LED assembly to increase from zero to a predetermined value.

Abstract: A restart circuit for causing an electronic ballast to perform a restart in response to reconnecting any lamp of a multiple lamp configuration of the electronic ballast to the electronic ballast is disclosed. The electronic ballast includes a filament health check circuit for providing a first current through a monitored filament of the lamps to a controller of the ballast. The controller restarts the electronic ballast when a determined ratio of the first current to a reference current indicates that the monitored filament has been disconnected or broken (i.e., the first current substantially decreases) and is subsequently replaced or reconnected to the ballast (i.e., the first current returns to a predetermined level). The ballast further comprises a dv/dt circuit for reducing the first current for a transient time period in response to reconnecting a filament other than the monitored filament to the ballast, causing the controller to restart the ballast.

Abstract: A ballast for driving one or more lamps includes a controller and a current reduction circuit for accelerating a controller reset. Upon detecting a fault, the controller disables the ballast for a preset period of time, and resets. The controller additionally resets when the ratio of a supplied second value to a supplied first value falls below a threshold value. The current reduction circuit reduces the supplied second value in less than the preset period of time, such that the ratio falls below the threshold value and the controller resets. An emergency lighting system includes the ballast as a primary ballast, a backup ballast, and a primary power source. The controller detects a fault if the primary power source de-energizes and the backup ballast disconnects the one or more lamps from the primary ballast. The current reduction circuit accelerates the reset of the controller when the primary power source de-energizes.

Abstract: An ignition controller that controls ignition of a discharge lamp discharging and emitting light between a pair of electrodes provided therein, the controller includes: an ignition device that ignites the discharge lamp, and a controller that controls a drive of the ignition device, in which the controller includes: a pulse applying unit that applies a high pressure pulse to the pair of electrodes by the ignition device, a direct current applying unit for applying a direct current to the pair of electrodes for a first period after applying the high pressure pulse, and an alternating current applying unit for applying a first alternating current to the pair of electrodes for a second period after the first period.

Abstract: A control circuit for use in a ballast configured for powering a first lamp set and a second lamp set. The second lamp set is operated via a controller and a second lamp driver circuit. The controller enables the second lamp driver circuit as a function of a monitored value corresponding to a current through a lamp of the second lamp set. The control circuit includes first and second input terminals for selectively connecting to the power supply. The control circuit reduces the monitored value as a function of a connection state of the first and second input terminals of the control circuit to the power supply. Thus, the control circuit causes the controller to selectively operate the second lamp driver circuit in order to energize the second lamp set in combination with the first lamp set.

Abstract: An electronic ballast has control circuitry to operate a gas discharge lamp in both full and dimmed illumination modes. The electronic ballast also includes a full power circuit having a power control coupled to the dimming controller output to receive the dimming controller signal, a filament heating circuit having a heating input coupled to a reduced power circuit to receive a reduced power signal and a heating output that can couple to the filaments of one or more lamps. When the full power circuit receives the dimming controller signal, via the power control, and the dimming controller signal is not in the dimming request range (i.e. the full illumination mode has been selected), the full power circuit generates a full power signal capable of driving/operating the lamp(s) in the full illumination mode. When the reduced power signal is present, the filament heating circuit generates and provides a filament heating signal to the filaments, via the heating output.