This paper elaborates the importance of modern frequency synthesizer techniques used in modern electronic system
and summarizes the trends of modern frequency sysnthesizer techniques to serialization
miniaturization
modularization and engineering practicability. The emphases are put on description of the latest progress of PLL frequency synthesizer and DDS which are used widely. Also
the advanced devices of monolithic PLL frequency synthesizer
ALL
monolithic DDS etc. and the advanced techniques of FLL