题目/Title：具有自动振幅控制的CMOS压控振荡器
                        CMOS voltage-controlled oscillator with automatic amplitude control

作者/Author：张利,吴恩德,王志华,陈弘毅
                        Li Zhang,Ende Wu,Zhihua Wang,Hongyi Chen

期刊/Journal：清华大学学报（自然科学版） Journal of Tsinghua University (Science and Technology)

年份/Issue Date：2006.July

卷（期）及页码/Volume（No.）&pages：Vol.46, No.7, pp. 1337 - 1340

摘要/Abstract：
调频范围是压控振荡器的一个重要的性能指标,当调频范围增大时,振荡器的振幅会随着频率的不同而改变。为了保证压控振荡器在调频范围内振幅恒定,提出了一种新型的自动振幅控制的电路结构。自动振幅控制电路由峰值检测、比较器和低通滤波器几部分构成,自动振幅控制电路与压控振荡器组成的反馈环路控制压控振荡器的输出恒定。电路采用标准的0.35μm CMOS工艺流片并进行测试。测试结果表明:压控振荡器的调频范围为18.2MHz~24.3MHz,达到了28.7%,自动振幅控制电路保证压控振荡器的振幅变化仅为8.7%。
The tuning range is an important performance parameter of voltage-controlled oscillators (VCO), but as the tuning range increases, the oscillator amplitude will vary at different frequencies. This paper presents a circuit for automatic amplitude control that ensures that the oscillators amplitude remains constant. The automatic amplitude control uses a peak detector, a comparator and a low pass filter. The automatic amplitude control is connected to the VCO by a feedback loop to keep the VCO output constant. The circuits were fabricated using a standard 0.35μm complementary metal oxide semiconductor (CMOS) process. The measured VCO tuning range was from 18.2MHz to 24.3MHz, for a range of 28.7% while the automatic amplitude control circuit ensures that the VCO amplitude only varies by 8.7%.