Methods and apparatus for synchronizing frequency dividers using a pulse swallowing technique

摘要

Methods and apparatus for synchronizing dividers in different LO paths using pulse swallowing. One example apparatus generally includes a first path having a first frequency divider configured to generate a first divided signal from a first periodic signal; a second path having a second frequency divider configured to generate a second divided signal from a second periodic signal; a phase detector configured to compare phases of a first sensing signal based on the first divided signal and a second sensing signal based on the second divided signal and to generate a first trigger signal if the first and second sensing signals are out-of-phase; and a first pulse suppressor configured to suppress a pulse of the first periodic signal for at least one cycle in response to the first trigger signal to adjust a phase of the first divided signal.

主权项

1. An apparatus, comprising:
a first circuit path having a first frequency divider configured to frequency divide a first periodic signal to generate a first divided signal; a second circuit path having a second frequency divider configured to frequency divide a second periodic signal to generate a second divided signal; a phase detection circuit coupled to the first and second circuit paths and configured to:
compare phases of a first sensing signal based on the first divided signal and of a second sensing signal based on the second divided signal; andgenerate a first trigger signal if the first and second sensing signals are out-of-phase; and a first pulse suppression circuit coupled to the phase detection circuit and configured to suppress a pulse of the first periodic signal for at least one cycle in response to the first trigger signal to adjust a phase of the first divided signal.