The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 25, 1987
Filed:
Sep. 03, 1985
Wilhelm Moring, Hamburg, DE;
Antonius H Nillesen, Eindhoven, NL;
Jurgen Ruprecht, Hamburg-Oststeinbek, DE;
U.S. Philips Corporation, New York, NY (US);
Abstract
In a circuit arrangement for deriving digital color signals from an analog television signal by means of an A/D converter, which forms a digital television signal from the analog television signal in synchronism with a clock signal which corresponds to a whole multiple of the line frequency of the television signal, and further by means of a demodulator, a first phase detector, a first phase calculator and a signal generator, which are interconnected in a phase-locked loop, interference-free demodulation of the chrominance signal in the composite television signal is guaranteed, even when the frequency of the clock signal fluctuates, in that the first phase calculator is supplied not only with a color phase signal from the first phase detector but also with a reference phase signal from a reference circuit which is a measure of the frequency difference or phase difference between the clock signal and a reference signal of stable frequency.