A low-phase-noise digitally controlled crystal oscillator for DVB TV tuners  

作　　者：赵薇 卢磊 唐长文 

机构地区：[1]State Key Laboratory of ASIC & System,Fudan University

出　　处：《Journal of Semiconductors》2010年第7期85-90,共6页半导体学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(No.60876019);the National S&T Major Project of China(No. 2009ZX0131-002-003-02);the Shanghai Rising-Star Program,China(No.09QA1400300);the National Scientists and Engineers Service for Enterprise Program,China(No.2009GJC00046).

摘　　要：This paper presents a 25-MHz fully-integrated digitally controlled crystal oscillator（DCXO） with automatic amplitude control（AAC）.The DCXO is based on Colpitts topology for one-pin solution.The AAC circuit is introduced to optimize the phase noise performance.The automatic frequency control is realized by a 10-bit thermometer-code segmental tapered MOS capacitor array,ensuring a～35 ppm tuning range and～0.04 ppm frequency step.The measured phase noise results are-139 dBc/Hz at 1 kHz and-151 dBc/Hz at 10 kHz frequency offset,respectively.The chip consumes 1 mA at 1.8V supply and occupies 0.4 mm^2 in a 0.18-μm CMOS process.This paper presents a 25-MHz fully-integrated digitally controlled crystal oscillator（DCXO） with automatic amplitude control（AAC）.The DCXO is based on Colpitts topology for one-pin solution.The AAC circuit is introduced to optimize the phase noise performance.The automatic frequency control is realized by a 10-bit thermometer-code segmental tapered MOS capacitor array,ensuring a～35 ppm tuning range and～0.04 ppm frequency step.The measured phase noise results are-139 dBc/Hz at 1 kHz and-151 dBc/Hz at 10 kHz frequency offset,respectively.The chip consumes 1 mA at 1.8V supply and occupies 0.4 mm^2 in a 0.18-μm CMOS process.

关 键 词：crystal oscillator DCXO phase noise supply pushing VCTCXO VCXO 

分 类 号：TN752[电子电信—电路与系统]