发明名称 |
Apparatus and method for synchronizing a horizontal deflection signal with a horizontal sync signal |
摘要 |
In an automatic frequency control circuit for synchronizing a horizontal deflection current of a television receiver with a horizontal sync signal, a bi-level signal which assumes either of two levels when the flyback pulse is or below a threshold value is produced, and a wider sync signal in synchronism with the horizontal sync signal and having a pulse width wider than the horizontal sync signal and equal to an odd multiple of the operating clock period is also produced. A phase comparator detects the difference in the number clock periods between a period period from a leading edge of the wider sync signal to an edge of the bi-level signal, and a period from the edge of the bi-level signal to a trailing edge of the wider sync signal. The detected difference is used to control a VCO. In an alternative configuration, a digital signal indicative of a magnitude of the flyback pulse during its rising or falling slope at an edge of the horizontal sync signal is produced and used for control of the VCO.
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申请公布号 |
US5677743(A) |
申请公布日期 |
1997.10.14 |
申请号 |
US19960726351 |
申请日期 |
1996.10.04 |
申请人 |
MITSUBISHI DENKI KABUSHIKI KAISHA |
发明人 |
TERAO, CHOJIRO;NISHINO, KO |
分类号 |
H03L7/08;H03L7/085;H03L7/087;H03L7/093;H03L7/181;H04N5/12;(IPC1-7):H04N5/50 |
主分类号 |
H03L7/08 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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