Abstract: An electronic ballast circuit includes a directly driven high frequency inverter circuit with a series resonant output circuit coupled to a load circuit having a high intensity discharge (HID) lamp and to a drive circuit dependent upon current flow in the load circuit. A starting circuit for the high frequency inverter is coupled to a DC source and to a charge storage and isolating circuit and provides initial energization to the high frequency inverter circuit. Also, a lamp starting circuit initiates increased conductivity of the high frequency inverter circuit which causes development of energy sufficient to "fire" an HID lamp whereupon a disablement circuit essentially removes the lamp starting circuit from the operational circuitry.

Abstract: An electronic ballast circuit includes a direct drive high frequency inverter circuit with a tuned output circuit and a drive circuit dependent upon current flow in a load circuit. The high frequency inverter circuit is coupled to a DC potential source which is derived from a pulsed DC potential source by way of a charge storage and charge isolating circuit. An oscillator provides a starting capability for the high frequency inverter circuit and is essentially removed from the active circuitry upon energization of the high frequency inverter circuit.