Patent ID: 9474121
Filing Date: 2016-10-18
CPC Classification: H05B

Claim Text:
1. A method, comprising: receiving a phase-cut dimming signal produced from an AC line voltage; comparing the phase-cut dimming signal to a threshold voltage and in response thereto outputting a digital phase-cut dimming signal; ascertaining a peak voltage level of the AC line voltage; ascertaining a duty cycle of the digital phase-cut dimming signal; employing the peak voltage level of the AC line voltage to ascertain a maximum value of the duty cycle of the digital phase-cut dimming signal; ascertaining a phase-cut angle of the phase-cut dimming signal from the duty cycle of the digital phase-cut dimming signal and the maximum value of the duty cycle of the digital phase-cut dimming signal; and controlling a dimming of an LED-based lighting unit in response to the phase-cut angle of the phase-cut dimming signal.