Automatic frequency control circuit

Details Automatic frequency control circuit Automatic frequency control circuit

H - Electricity

03

L

328/28

H03L 7/08 (2006.01) H03L 7/191 (2006.01) H03L 7/199 (2006.01) H04N 5/932 (2006.01)

Patent

CA 2012280

An AFC circuit for use in a chrominance signal processing circuit of a VTR basically includes a NCO (9), a frequency divider (9, 10, 11, 12, 13) for frequency-dividing an output of the NCO, and a phase comparing circuit (17) for comparing phases, of the output of the divider and a horizontal synchronizing signal extracted from an inputted video signal to supply an error output to the VCO. When a phase relation between the output of the divider and the horizontal synchronizing signal becomes a miss-locked state out of the phase-locked state, a frequency-dividing operation is stopped at a timing corresponding to a rise of a normal inputted signal in a phase-locked state and the frequency-dividing operation is restarted after the inputted horizontal synchronizing signal is counted by a predetermined number. As a result, the phase-locked state of the inputted horizontal synchronizing signal and the output signal of the divider is forcibly restored.

Affiliated with

Also associated with

Rating

Automatic frequency control circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Automatic frequency control circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic frequency control circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1347528