| 摘要 |
PURPOSE:To set sufficient follow-up properties to a slice level of a video signal by providing a comparator circuit comparing an output from a clamp circuit clamping the minimum level of a video signal with an output from a reference signal changing circuit. CONSTITUTION:A video signal slice level setting circuit uses a D/A converter 7 to decide the maximum amplitude level Vb of a video signal as a reference voltage, the reference voltage Vb is divided by a D/A converter 8 to form a slice level. Then a video signal clamped to a clamp voltage V0 depending on the circuit is subjected to A/D conversion and digitized and outputted to a digital signal serial output line 12. A buffer amplifier 5 and a level clamp circuit 6 can be simple circuits and a low-speed circuit is enough for the D/A converters 7, 8. Thus, the slice level of the video signal is set with sufficient follow-up properties with simple circuit constitution without using an expensive element.
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