Dimming control circuit having feedback frequency control

摘要

A feedback dimming control circuit for controlling the luminance of a plurality of lamps, the circuit comprising: a multiplier receiving and multiplying a feedback current and an input voltage, a first subtracter generating an error signal by subtracting an output voltage from the multiplier from a reference voltage, a second subtracter subtracting a signal responsive to the error signal from the input voltage, an oscillator generating a periodic signal in response to the output of the second subtracter; and a tank resonating in response to the periodic signal and generating the feedback current.