04437072 is referenced by 73 patents and cites 3 patents.

A phase-locked loop circuit comprising a reference oscillator (1), a reference frequency divider (2) for dividing the output signal of the reference oscillator, a programmable frequency divider (3), a phase comparator (4) for monitoring the difference in phase between the output signal of the two frequency dividers, a lock detector (11) for generating a first signal which is pulse-shaped or rectangular when the above-mentioned difference in phase is generated, and a digital signal maintaining circuit (100) for converting the first signal into a second directed current signal.

Title
Lock detecting circuit for phase-locked loop frequency synthesizer
Application Number
179898
Publication Number
4437072
Application Date
September 21, 1982
Publication Date
March 13, 1984
Inventor
Fumitaka Asami
Kunitachi
JP
Agent
Staas & Halsey
Assignee
Fujitsu
JP
IPC
H03L 7/18
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