Electronic ballast for fluorescent lamp

摘要

A transformerless ballast for a gaseous discharge lamp is disclosed. The ballast comprises: a rectifier; a filter for the rectifier output; a voltage divider for the filter output; an electronic gate modulating the filter output to power a lamp when the lamp is lit; a controller controlling the electronic gate responsive to variations in load current and lamp impedance and to variations in the voltage divider output; an oscillator generating an output for predetermined period of time until after the lamp is lit; and an amplifier receiving and amplifying the oscillator output for powering the lamp when the lamp is unlit.