Accession Number:

ADD005937

Title:

Digital Phase-Frequency Detector.

Descriptive Note:

Patent Application,

Corporate Author:

DEPARTMENT OF THE AIR FORCE WASHINGTON D C

Personal Author(s):

Report Date:

1979-02-16

Pagination or Media Count:

9.0

Abstract:

A digital phase-frequency detector which provides rapid frequency acquisition and phase control when used in phase-locked loop applications. In a locked condition the output of a pair of flip-flop circuits are high causing an EXOR gate to produce a detector output, when unlocked a phase difference will increase until the higher frequency exhibits two positive transitions before one positive transition of the lower frequency can propagate through the circuit, this will cause the flip-flop receiving the higher frequency to change state thereby preventing the EXOR gate from gating and the other flip-flop from changing state, the flip-flop therefore controls the detector output until the two input frequencies again coincide and the output controlled by the EXOR gate. Author

Subject Categories:

  • Electrical and Electronic Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE