Abstract: A circuit and method for running a metal halide arc discharge lamp from an AC power source. The circuit includes a rectifier for producing a DC voltage. The lamp is resistively ballasted by a current limiting filament connected in series with the lamp. The circuit includes a switch that closes during start up of the lamp so that the resistive filament is energized to provide immediate light prior to the lamp entering the normal run mode.

Abstract: Ballast circuitry for a metal halide lamp is disclosed enabling sustained operation with a typical 120 volt AC power source. A novel auxiliary circuit network is operatively associated with inductive type starting circuit means to provide lamp reignition when needed during each half-cycle of the AC power supply. The present auxiliary circuit network employs breakover switching means connected in series with capacitor storage means for further connection across the operating discharge lamp.

Abstract: A lamp driver circuit is presented herein for driving a lamp circuit with an AC squarewave voltage at a relatively high frequency. The driver circuit includes a self-oscillating half-bridge circuit having a pair of input terminals connected across a DC voltage supply, which may be obtained from rectifying an AC voltage signal, and a pair of output terminals connected across a lamp circuit including a lamp, either a resistive lamp or a gaseous discharge lamp, to be energized. The circuit also includes a pair of capacitors connected together in series across the input terminals and having a junction therebetween connected to a first one of the output terminals. The bridge circuit also includes first and second switching transistors connected together in series across the input terminals.

Abstract: A ballast circuit and method of operating gas discharge lamps are disclosed. The ballast circuit generates a relatively low frequency regulated square-wave current which advantageously provides for operating the gas discharge lamps during their run mode. The square-wave current delivered to the electrodes of the gas discharge lamp reduces or substantially eliminates the cataphoresis effects typically created by D.C. and 60 Hz operation of the gas discharge lamp while also reducing or substantially eliminating the detrimental acoustics resonance effects typically created by operating the gas discharge lamps at relatively high frequency of excitations.

Abstract: A piezoelectric transformer signal coupler utilizes a drive circuit including an oscillator constructed to excite the primary of a piezoelectric transformer at its characteristic anti-resonant frequency. Positive feedback signals modulated by the time domain response characteristic of the particular piezoelectric transformer force the oscillator to lock onto its characteristic anti-resonant frequency despite variations thereof due to temperature drift and secondary loading. The resulting drive circuit is implementable as a miniature, low mass integrated circuit mountable on the transformer's piezoceramic wafer to create a signal coupler of a single integrated structure.

Abstract: A lighting unit having a filament serving as a supplementary light source, an improved gas discharge tube serving as a main light source having improved electrodes and an improved ballast circuit operating in cooperation with the improved electrodes is disclosed. Various embodiments of the improved electrodes and various embodiments of the improved ballast circuits are disclosed. The improved ballast circuit operating in cooperation with the improved electrodes provides for thermionic arc conditions in the operation of the gas discharge tube substantially immediately after the application of voltage applied to the unit.

Abstract: Ballast circuits for a gas discharge tube are disclosed. One embodiment of a single-phase non-inductive ballast for operation of a gas discharge tube by direct current (D.C.) using a resistive current-limiting means and a relatively small capacitor is disclosed. The D.C. ballast circuit generates a timed pulse addition (TPA). The D.C. ballast circuit includes an arrangement of switching means which controls the discharge of a capacitive energy storage means so as to supply the reignition and the restrike energy in the form of timed pulse additions (TPA) that may be needed for the gas discharge tube. Other embodiments are disclosed for the ballast circuit which operate directly from the A.C. line and control the discharge of a capacitive storage means to supply reignition and restrike energy in the form of timed pulse additions (TPA) that may be needed for the gas discharge tube.