| 摘要 |
PROBLEM TO BE SOLVED: To provide a data slicing circuit that generates an optimum data slice level with respect to VBI(vertical blanking interval) signals having different different standards to separate data. SOLUTION: The data slice circuit is provided with a line detection circuit 33, that outputs a line detection pulse PLC only in the case of detecting a line with a VBI signal having a CRI(clock-run-in) signal superimposed thereon, and outputs a line detection pulse PLR only for a period, when detecting a line with a VBI signal having a reference signal superimposed thereon, a window pulse generating circuit 34 that outputs pulses PCRI, PPED to change a period averaging the VBI signal in response to the pulses PLC, PLR, a data slice reference voltage detection circuit 35 that samples and holds the average voltage of the VBI signal clamped for a period of output pulses PCR, PPED only, and a data slicing level generating circuit 37, that adds a DC voltage changed in response to the detected pulses PLC, PLR to an output voltage of the circuit 35.
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