TWO-WIRE DIMMER SWITCH WITH IMPROVED ZERO CROSS DETECTION

• Main Authors: KITE, Henry, ZOTTER, William, YANG, Bingrui
• Format: Patent
• Language: English; French; German
• Published: 16.11.2022
• Subjects: ELECTRIC HEATING; ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY

A two-wire lighting control device including a controllably conductive device (508), a signal generation circuit (522), and a filter circuit (526). The controllably conductive device receives an AC line voltage and supplies a phase-control signal to a load by being conductive for a first duration of time and non-conductive for a second duration of time within a half-cycle of the AC line voltage. The signal generation circuit generates a non-zero-magnitude signal. And, the filter circuit receives a signal from the controllably conductive device during the first duration of time and the non-zero-magnitude signal from the signal generation circuit during the second duration of time. The non-zero-magnitude signal is adapted to fill-in or complement the signal from the controllably conductive device, so that any delay variation as a function of the firing angle of the controllably conductive device through the filter circuit is mitigated by the presence of the non-zero-magnitude signal.