自动幅度控制电路在射频CMOS电感电容振荡器中的应用及原理分析  

Analysis and Application of Automatic Amplitude Control Circuit in CMOS Radio Frequency LC Oscillator

作　　者：刘慧敏[1,2] 张小兴[1] 戴宇杰[1] 吕英杰[1] 

机构地区：[1]南开大学微电子研究所,天津300071 [2]天津理工大学电子信息工程学院,天津300191

出　　处：《南开大学学报（自然科学版）》2010年第6期99-103,共5页Acta Scientiarum Naturalium Universitatis Nankaiensis

基　　金：天津市教委基金资助项目(SB20080048)

摘　　要：分析推导了互补金属氧化物半导体(CMOS)电感电容振荡器的电压振荡幅度与相位噪声的关系.采用自动幅度控制电路控制射频CMOS电感电容振荡器,在0.18μm CMOS工艺下进行Candence SpectreRF仿真,在3.4 GHZ时,1 MHz频偏处相位噪声最差值采用自动幅度控制电路为-113.3 dBc/Hz,不采用自动幅度控制电路为-105.1 dBc/Hz.在不同频率下对振荡器相位噪声仿真结果表明,当频率变化从3.16～3.4 GHz时,采用自动幅度控制电路的相位噪声都低于不采用自动幅度控制电路的相位噪声.由此得出通过控制振荡器振动振幅,提高品质因数,可以降低振荡器相位噪声.Relationship between voltage oscillation amplitude and phase noise was deducted and analyzed.A circuit was realized through 0.18μm CMOS process with the amplitude control circuit（AAC）.The simulation was made with the Cadence design system SpectreRF simulator tool.The worst phase noise was -113.3 dBc/Hz with AAC and -105.1 dBc/Hz without AAC at 1 MHz away from 3.4 GHz,The simulation was made under different frequency,from 3.16 to 3.4 GHz.Phase noise of circuit with AAC was always lower than that without AAC. Results of simulation confirm that phase noise of oscillator circuit can be reduced through increasing quality factor by controlling voltage amplitude.

关 键 词：自动幅度控制 CMOS电感电容振荡器 相位噪声 品质因数 

分 类 号：TN402[电子电信—微电子学与固体电子学]