宽带VCO自动幅度控制电路中检幅电路的设计

Design of a New Peak Detector in AAC of Wide Band VCO

设计了一种新型的幅度检测器用于宽带CMOSVCO的自动幅度控制电路中,通过AAC确保了VCO在整个带宽内能够可靠的起振,同时,新的幅度检测器解决了传统幅度检测电路导致的VCO相位噪声恶化的问题。基于Chartered0.25μm CMOS工艺的测试结果表明,在AAC电路运用新型的检幅电路后,VCO在全波段能够可靠起振同时获得较好的相位噪声特性,偏移中心频率10k处的相噪能改善6dBc。

This paper presents a new peak detector（PD） for the AAC in a wideband CMOS VCO. By using this new PD the reliability of the VCO can start-up reliably and the problem of phase noise degrading when using the traditional PD is solved. The chip is implemented in 0.25μm CMOS process. The test results show that by using the new PD in the AAC, the VCO can startup reliably and get better phase noise performance, the phase noise of the VCO at 10 kHz offset can be lower by about 10 dBc.