Direct current power source for an electric discharge lamp using reduced starting current

摘要

A solid-state electronic ballast circuit for supplying direct-current power to an electric discharge vapor lamp is disclosed. The source-drain channel of a Vertical Metal Oxide Semiconductor (VMOS) Field Effect Transistor (FET) is connected in series with the lamp across a DC source. A resistance network controls the conductivity of a bipolar transistors, which in turn controls the conductivity of the VMOS channel, in response to variations in channel voltage, lamp voltage and lamp current.