Design of a 2.06 GHz～3.43 GHz Frequency Synthesizer with Auto-Calibration Loop

A kind of auto-calibration frequency synthesizer was proposed.By using the switch electric capacity array,this design can be made it work in a low phase noise and a wide tuning range.The adaptive control return route enables this synthesizer to act,according to the parameters such as the input reference frequency,the input temperature and the rate of requency devision,on turning off or turning on switches in the automatic control switch array,and achieves fastly the fixed aiming goal.The SMIC 0.18μm CMOS craft is provided to carry on the simulation.Finally the frequency synthesizer demonstrates its output frequency range from 2.06 GHz to 3.43 GHz (50%),the worst phase noise -127.9 dBc/Hz at 1 MHz,its power loss about 12 mW under the supply voltage 1.8 V.