Two-wire dimmer with improved zero-cross detection
First Claim
1. A lighting control device comprising:
- a controllably conductive device for supplying an AC line voltage to a load in response to a drive signal, wherein the controllably conductive device is non-conductive for a first duration of time and is conductive for a second duration of time, wherein the first duration of time and the second duration of time are within the same half-cycle of the AC line voltage;
a control circuit configured to;
receive a signal from the controllably conductive device that represents a voltage developed across the controllably conductive device during the first duration of time;
generate a sine-wave-shaped signal that complements the voltage developed across the controllably conductive device during the second duration of time; and
filter the signal from the controllably conductive device during the first duration of time and the sine-wave-shaped signal during the second duration of time.
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Accused Products
Abstract
A lighting device, such as a two-wire lighting control device, may include a controllably conductive device and a control circuit. The controllably conductive device may supply an AC line voltage to a load in response to a dive signal such that the controllable conductive device is non-conductive for a first duration of time and conductive for a second duration of time within a half-cycle of the AC line voltage. The control circuit may receive a signal from the controllably conductive device that represents a voltage developed across the controllable conductive device during the first duration of time. The control circuit may generate a sine-wave-shaped signal that complements the voltage developed across the controllably conductive device during the second duration of time. The control circuit may also filter the signal from the controllably conductive device during the first duration of time and the sine-wave-shaped signal during the second duration of time.
63 Citations
15 Claims
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1. A lighting control device comprising:
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a controllably conductive device for supplying an AC line voltage to a load in response to a drive signal, wherein the controllably conductive device is non-conductive for a first duration of time and is conductive for a second duration of time, wherein the first duration of time and the second duration of time are within the same half-cycle of the AC line voltage; a control circuit configured to; receive a signal from the controllably conductive device that represents a voltage developed across the controllably conductive device during the first duration of time; generate a sine-wave-shaped signal that complements the voltage developed across the controllably conductive device during the second duration of time; and filter the signal from the controllably conductive device during the first duration of time and the sine-wave-shaped signal during the second duration of time. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
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Specification