摘要 |
Provided herein are self-calibrating timing circuits and methods for use in a sync separator. A comparator compares a video signal to a video reference voltage to produce a sliced sync signal that has a frequency that is equal to a scan frequency of a horizontal sync embedded in the video signal. A frequency-to-voltage converter converts the sliced sync signal to a voltage control signal having an amplitude that is inversely proportional to the scan period of the horizontal sync embedded the video signal. A voltage-to-timed interval converter that converts the voltage control signal to a timer signal that has timed intervals that are that are inversely proportional to the amplitude of the voltage control signal, and thus proportional to the scan period of the horizontal sync embedded in the video signal. These timed intervals produced in accordance with embodiments of the present invention are easily and precisely scalable, allowing them to be used to discriminate various timing features embedded in video signals. This abstract is not intended to be a complete description of, or limit the scope of, the invention.
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