| 摘要 |
PURPOSE:To obtain a correct time reference and a phase reference by providing a ROM, an address circuit, PLL, a selection circuit, a D/A converter and a low-pass filter. CONSTITUTION:A clock of 960fH is divided into 1/5 in a burst sink generating circuit 5 to have 192fH and a 768fHVCO9 output signal is divided into 1/4 to have 192fH to perform the comparison of phase in a phase comparator 8. When the voltage corresponding to the detected phase difference is applied to the 768fHVCO9, the clock of a central frequency 768fH is obtained. Based on this clock, the address circuit 11 is operated, the data of the burst sink of 2 bits written in the ROM13 is read. A vertical synchronizing signal for the first field, a vertical synchronizing signal and a horizontal synchronizing signal for the second field are selected by the selection circuit 14, converted into an analog signal by the D/A converter 17 and passed through the low-pass filter 18. Thereby, the burst sink of the correct time reference and the phase reference can be obtained.
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