Abstract: A transformer bobbin has a body with first and second ends spaced along a longitudinal axis. Conductive pins are mounted in the ends and dimensioned for electrical and mechanical connection with first and second wire windings received in the body. An opening in the body is dimensioned to receive a ferrous core, and an external winding surface on the body extends between the first and second ends. First and second margin barriers are provided inwardly of the first and second ends of the winding surface. The margin barriers have a height that extends a predetermined dimension that closely approximates the height of the first winding. The margin barriers electrically isolate the first winding from the second winding that is thereafter received over the body. Preferably, at least one of the first and second margin barriers includes channels therethrough dimensioned to receive the first winding wire for connection with the pins.

Abstract: A ballast operates lamps each including a pair of electrodes. A high frequency resonant circuit generates a high frequency bus, the resonant circuit is configured for operational coupling to the electrodes of each lamp, and includes a resonant inductor and a resonant capacitance.

Abstract: For safety reasons, industrial lighting fixtures are required to have backup lighting systems so that if the primary lights should fail, there will still be enough light to ensure safe maneuvering. Typically these backup lighting systems have their own power or drive source. The present application contemplates a lighting ballast circuit that is able to power a primary high intensity discharge (HID) lamp and is also able to power an auxiliary lamp in the event of temporary or permanent failure of the HID lamp.

Abstract: A continuous mode electronic ballast operates a lamp. A buck converter is configured to generate a direct current (DC) bus voltage at buck converter output. An inverter circuit is operationally coupled to the buck converter output, and configured to receive the DC voltage and convert the DC voltage into an AC voltage to drive the lamp. A short circuit protection circuit is operationally coupled to the buck converter output to sense the DC bus voltage, compare the sensed DC voltage to a predetermined threshold and, based on the comparison, shut down the inverter circuit.

Abstract: A buck converter generates a direct current (DC) bus voltage at a buck converter output. An inverter circuit is coupled to the buck converter and configured to receive the generated DC voltage and convert the DC voltage into an alternating current (AC) voltage to drive a lamp. A power control circuit is coupled to the buck converter output and configured to provide a control voltage signal to the buck converter so that the buck converter generates the DC voltage and current of a predetermined value. A crest factor reduction circuit is coupled (a) to the buck converter output to sense a rate of change in the generated DC bus voltage, and (b) to the power control circuit to modify the control voltage signal based on the sensed rate of change in the DC bus voltage.

Abstract: A rectifying circuit converts an alternating current (AC) voltage to a first direct current (DC) voltage. A filter filters the rectified first DC voltage and outputs the filtered first DC voltage which includes an alternating current (AC) voltage component or ripple voltage at filter output. A buck converter receives the filtered first DC voltage and generates a second direct current (DC) bus voltage. A power control circuit is coupled to the buck converter and provides a control voltage signal to the buck converter so that the buck converter generates the second DC voltage of a predetermined value. A ripple detection circuit is coupled to the filter output and detects the ripple voltage in the filtered first DC voltage, based on which the power control circuit modifies the control voltage signal so that the second DC voltage includes a predefined level of the ripple voltage.

Abstract: A lamp ballast starting circuit and method for a gas discharge lamp is disclosed. The ballast starting circuit includes the inputs of the starting circuit connected to an inverter circuit, the starting circuit generating a pulse at the leading edge of each alternating half cycle of the inverter circuit output, the polarity of the pulse being the same as the polarity of each alternating half cycle of the inverter circuit output. The output of the starting circuit starts a gas discharge lamp.

Abstract: The embodiment disclosed herein relates to a lighting system that includes an auxiliary lighting circuit for use with an electronic HID ballast. The lighting system comprises a power supply configured to provide power to a high intensity discharge (HID) lamp via an electronic ballast and a ballast power sensing component configured to determine the amount of power drawn by the electronic ballast and to convert this power drawn by the electronic ballast to a scaled voltage that is representative of the power drawn by an HID ballast. A lamp driver component is configured to provide power to an auxiliary lamp via the same power supply when the scaled voltage reaches a triggering threshold. A voltage regulation component is configured to regulate the power delivered to the auxiliary lamp such that the auxiliary lamp power stays within a predefined range.

Abstract: An integrated lamp/lamp electronics unit includes a lamp having a first end with first end electrical terminals, and a second end with second end electrical terminals. An end cap having an interior section is placed into electrical connection with the first end electrical terminals at the first end of the lamp. Lamp electronics are configured to control operation of the lamp and are connected only to the second end electrical terminals. The lamp electronics are carried on a circuit board having a configuration substantially matching the second end of the lamp portion. The circuit board is placed within the interior of a lamp electronics end cap, and the end cap is attached in a permanent relationship to the second end of the lamp.

Abstract: In accordance with one aspect of the present application a ballast for operating a lamp includes an inverter circuit configured to generate a control signal. A resonant circuit is configured for operational coupling to the inverter circuit and to the lamp to generate resonant voltage in response to receiving the control signal from the inverter circuit. A clamping circuit is operationally coupled to the resonant circuit to limit the voltage across the resonant circuit. A multiplier circuit is operationally coupled to the resonant circuit to boost the voltage clamped by the clamping circuit to a value sufficient to permit starting of the lamp. A pulsing circuit includes a power controller to pulse the inverter “ON” and “OFF,” and a charge pump circuit to operate the power controller. The charge pump circuit is operationally coupled to the clamping circuit to derive electrical power from the clamping circuit.

Abstract: In accordance with one aspect of the present application, a continuous mode electronic ballast for operating an HID lamp includes an inverter circuit configured to generate a control signal. A resonant circuit is operationally coupled to the inverter circuit and to the lamp and configured to generate resonant voltage in response to receiving the control signal generated by the inverter circuit. A clamping circuit is operationally coupled to the resonant circuit to limit the voltage across the resonant circuit to protect components of the ballast. A multiplier circuit is operationally coupled to the resonant circuit to boost the voltage clamped by the clamping circuit to a value sufficient to permit starting of the lamp. The clamping circuit and the multiplier circuit cooperate to facilitate a continuous starting of the lamp.

Abstract: In accordance with one aspect of the present application, a continuous mode voltage fed inverter includes a resistor starting network configured to start a charging of the inverter. A resonant feedback circuit is configured to generate an oscillating signal following the starting of operation of the circuit by the resistor starting network. A complementary switching network has a pair of complementary common source connected switches configured to receive the oscillation signal generated by the resonant feedback circuit, wherein the oscillation signal determines a switching rate of the complementary pair of switches. A clamping circuit is configured to maintain an inverter current in an inductive mode, wherein the inductive current lags voltage across the pair of complementary common source connected switches. A fold-back circuit is connected, in one embodiment, to the complementary switching network to provide a two-level clamping action.

Abstract: In an electric lighting fixture, a lighting ballast circuit is provided. The circuit includes a lamp portion, a switching portion, and a drive portion. The lamp portion receives a light source 10. The drive portion is configured to supply signals to the switching portion. The switching portion includes first and second transistors 20, 22 that alternate periods of conductivity. First and second diodes 34, 36 in anti-parallel combinations with the first and second transistors 20, 22 help prevent reverse current flow through the transistors 20, 22. Third and fourth diodes 44, 46 in series combination with collectors of the transistors 20, 22 further help prevent reverse current flow through the transistors 20, 22. The first and second diodes 34, 36 route current from the drive portion via a path that by-passes the transistors 20, 22 so the transistors do not dissipate the power resultant from reverse current flowing thereacross.

Abstract: The present invention provides a ballast circuit powered by a system power source. The ballast, in operative connection with the system power source, is an inverting type of ballast designed to generate an asymmetric alternating lamp input current on a lamp input line. Further, a gas discharge lamp is in operative connection to the lamp input line configured to receive the asymmetric alternating current. The inverting circuit of the ballast is configured with complementary switches configured to have unequal on times, thereby producing an asymmetric lamp input current. A DC blocking capacitor is provided to block any DC current from the lamp input line. The asymmetric alternating lamp input current eliminates visual striations otherwise occurring in the lamp.

Abstract: In accordance with one aspect of the present application, a continuous mode voltage fed inverter includes a resistor starting network configured to start a charging of the inverter. A resonant feedback circuit is configured to generate an oscillating signal following the starting of operation of the circuit by the resistor starting network. A complementary switching network has a pair of complementary common source connected switches configured to receive the oscillation signal generated by the resonant feedback circuit, wherein the oscillation signal determines a switching rate of the complementary pair of switches. A clamping circuit is configured to maintain an inverter current in an inductive mode, wherein the inductive current lags voltage across the pair of complementary common source connected switches. A fold-back circuit is connected, in one embodiment, to the complementary switching network to provide a two-level clamping action.

Abstract: An electrical power conversion system for converting power from one voltage to another, especially for converting a higher-voltage, direct current electrical power system, such as a thirty-six volt to forty-two volt (36V-42V) direct current system for vehicles, into a voltage acceptable for powering lower voltage equipment, such as those using twelve volt to fourteen volt (12V-14V) DC vehicle electrical power systems is disclosed. The invention provides the ability to control the operating states of the loads by coupling a control signal to the vehicle's electrical power bus. The invention can take advantage of current or future DC-to-AC inverter or DC-to-DC converter technology and anticipated vehicle electrical systems to devise a electrical power conversion and control system meeting the needs of various vehicle loads.

Abstract: A plurality of lighting ballasts (12, 14, 16) draw power from a single DC bus signal. A power factor correction circuit (10) rectifies and smoothes AC power to produce the DC bus signal. In order to prevent damage to the ballast (12) when a lamp (18) dies or is removed, the ballast (12) includes an AC switch that senses damaging conditions and responds by changing a resonant frequency of the ballast (12). The AC switch operates in 2-3 second cycles. While it is operative, it shunts current away from inductors (38, 40) of the ballast (12) causing a resonant frequency of the ballast (12) to change. At the end of the cycle, the switch turns off, but if a load fault is still present in the ballast (12) it activates again. Preferably, the AC switch has a response time of approximately 500 &mgr;s.

Abstract: A plurality of lighting ballasts (12, 14, 16) draw power from a single DC bus signal. A power factor correction circuit (10) rectifies and smoothes AC power to produce the DC bus signal. In order to prevent damage to the ballast (12) when a lamp (18) dies or is removed, the ballast (12) includes an AC switch that senses damaging conditions and responds by changing a resonant frequency of the ballast (12). The AC switch operates in 2-3 second cycles. While it is operative, it shunts current away from inductors (38, 40) of the ballast (12) causing a resonant frequency of the ballast (12) to change. At the end of the cycle, the switch turns off, but if a load fault is still present in the ballast (12) it activates again. Preferably, the AC switch has a response time of approximately 500 &mgr;s.

Abstract: An inverter circuit for ballasting a gas discharge lamp having a delay circuit designed to delay regenerative control of the inverter switches until a d.c. bus has attained steady-state operating d.c. voltage. The inverter circuit includes a drive control circuit for inducing an a.c. load current. The inverter circuit includes first and second complementary switches serially connected between the bus and a reference bus. The switches are connected together at a common node through which the a.c. load current flows. A driving inductor is connected at one end to the common node and operatively connected at the remaining end to a control node. A load circuit includes a resonant inductor connected at one end to the common node, with the resonant inductor mutually coupled to the driving inductor. A resonant capacitor is serially connected between the remaining end of the resonant inductor and the reference bus. The gas discharge lamp is serially connected with a d.c.

Abstract: A ballast circuit is provided, comprising: a plurality of inverters, each inverter for powering a load; and a controller operationally coupled to a shutdown control signal of each inverter for selectively shutting down any combination of inverters. In another aspect, the controller is for selectively disabling any combination of inverters to effectively disconnect the load associated with each disabled inverter. The controller is for receiving communications from a control device, each communication a selection of 0%, “n−1” approximate percentages each associated with a ratio of “1” through “n−1” loads to “n” loads, where “n” is the total number of loads powered by the inverters of the ballast circuit and where the numerator for each ratio is an integer between “1” and “n−1,” inclusive, or 100% light from the combined loads powered by the inverters of the ballast circuit.