Television – Synchronization – Automatic phase or frequency control
Patent
1996-03-06
1998-06-02
Grant, Christopher C.
Television
Synchronization
Automatic phase or frequency control
348540, H04N 512
Patent
active
057608393
ABSTRACT:
A horizontal synchronizing apparatus includes a source for providing a horizontal synch. signal, a horizontal deflection circuit for generating a deflection current having scanning intervals and blanking intervals repetitively successing in response to driving pulses and having retrace pulses which delay from the driving pulses as a function of a load on the horizontal deflection circuit, a phase locked loop having an input, an output and a first feedback path, for producing from the output a substantial bi-level signal synchronized to the horizontal synch. signal applied to the input, and a phase controlled loop having an input, an output and a second feedback path, for maintaining the retrace pulses synchronous with the bi-level signals. The phase controlled loop has a phase detection circuit having a first input connected to the output of the phase locked loop and a second input connected to the deflection circuit, for producing a first polarity current in response to the bi-level signal when the retrace pulses are in a first state or a second polarity current in response to the bi-level signal when the retrace pulses are in a second state, a filter connected to the phase detection circuit for producing a control signal by filtering out undesired components of the first and second polarity signals, and a phase controllable device having a control input coupled to the output of the filter for producing the driving pulse which maintains the retrace pulses synchronous with the bi-level signals.
REFERENCES:
patent: 3891800 (1975-06-01), Janssen et al.
patent: 4063133 (1977-12-01), Nero et al.
patent: 4327376 (1982-04-01), Balaban et al.
patent: 4351001 (1982-09-01), McGinn et al.
patent: 4467359 (1984-08-01), Hosoya
patent: 4769705 (1988-09-01), Lendaro
patent: 4803407 (1989-02-01), Mehrgardt
patent: 5619276 (1997-04-01), Christopher et al.
S. Coccetti et al., "A New Custom-Made I.C. for Monitors," IEEE International Conference on Consumer Electronics, Jun. 10, 1988, pp. 78-79.
Patent Abstracts of Japan, vol. 6, No. 123, Jul. 8, 1982, p. 1, JP-A-57 052 271.
Grant Christopher C.
Kabushiki Kaisha Toshiba
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