BALLAST CIRCUIT WITH INDEPENDENT LAMP CONTROL

摘要

A ballast circuit independently energizes first and second lamps. In one embodiment, an inverter provides a drive signal for energizing the first and second lamps. A first signal detection circuit detects a first AC input sign al and a second signal detection circuit detects a second AC input signal, each of which energizes a respective one of first and second lamps. A first lamp control circuit receives a signal from the first signal detector such that t he first lamp is energized by the drive signal when the first AC input signal i s present. Similarly, a second lamp control circuit receives a signal from the second signal detector such that the second lamp is energized by the drive signal when the second AC input signal is present.