| 摘要 |
A modular electronic ballast is provided for powering a fluorescent lamp. A motherboard is configured to receive an AC input signal, one or more supplemental input signals and a feedback signal from the lamp. A ballast control circuit generates an output signal for an oscillating inverter driving the lamps. A daughter card is coupled to the motherboard and selected from a plurality of daughter cards, each configured to provide a dimming control signal having predetermined characteristics and readable by the control circuit. The daughter cards are collectively configured to provide dimming control signals in response to each of a line-coupled demand response interface, one or more digitally addressable interfaces, analog dimming signals received via said supplemental communications bus, and three-wire phase control signals received via said AC line and said supplemental communications bus. The motherboard is configured to interchangeably receive any one of the daughter cards. The ballast control circuit is effective to generate output signals in response to the feedback signal, dimming control signal and a predetermined lamp output value. |
