這一篇論文提出一個新型弦波式壓控振盪器，而這個新型振盪器是僅由兩個OTA-C所構成。相較於以往的震盪器設計，所需的OTA數目明顯的減少。弦波震盪器在以往的電路設計中，並沒有到達100MHz的論文出現，所以論文中所提及的電路設計，也是對於OTA-C 震盪器做一個中頻段頻操作設計。
為了做一些相關的討論，第二章中會有RLC並聯電路的推導會在這論文中出現。在論文當中，舊有的電路也介紹了一些，轉移函數也有所提及。所提出來的振盪器是放在第四章介紹。在OTA中，為了提高輸出阻抗，所以使用折疊式串接電路。也因為一般OTA輸出電位是浮接的，所以變動會太過大。所以，我們外加了共模回授電路，提供一個受控制的位準。振盪器的振盪頻率約100MHz左右，輸出振幅在100mV，而輸出弦波的Q 值則為50。
在模擬的結果?堙A輸出弦波的振幅控制機制有效的壓抑諧波的出現。對照過這一兩種新舊電路的性能，我們發現了些本來沒有預期到的效應出現，在論文的後頭我們對這些現象會提出解釋。

Abstract

In this research, we intend to develop a sinusoidal VCO with low harmonic distortion.
A new sinusoidal VCO is developed with only two OTAs. The number of OTAs is fewer than that previously presented in other papers. The oscillator will be
easy to debug and the complexity of the oscillator can be reduced.
An AGC control mechanism is applied to the VCO to control the oscillation amplitude and to reduce the harmonic distortion.
The oscillation is designed with the frequency around 100MHz and the oscillation amplitude is around 100mV. The simulation results and the problem encountered are discussed.

Content

Abstract

Chapter 1. Introduction

Chapter 2. Basics Theory of RLC parallel circuits and poles
Section 2.1 Basics of RLC parallel circuits
Section 2.2 Relation between poles and the output system

Chapter 3. Previous VCO structures
Section 3.1 Ideal OTA
Section 3.2 Previous VCO structure
Section 3.2.1 Basic system oscillator core (without amplitude control) Section 3.2.2 Amplitude control ( poles control ) mechanism
Section 3.3 OTA realized the structures of oscillator

Chapter 4. Proposal
Section 4.1 A new structure of OTA-C circuit
to realize Parallel RLC oscillation circuit
Section 4.2 The transfer function T(s) of the oscillator
Section 4.3 The feedback circuit for the amplitude control
Section 4.4 The detail circuit of OTA in our VCO
Section 4.4.1 Original OTA
Section 4.4.2 Common-Mode-Feedback

Chapter 5. Simulation result
Section 5.1 performance of the OTA
Section 5.1.1 Transconductance of the OTA
varies with input amplitude
Section 5.1.2 OTA frequency response
Section 5.1.3 Common mode feedback performance

Section 5.2 Output of oscillator
Section 5.2.1 Output sinusoidal wave spectrum of Oscillator
Section 5.2.2 Feedback Control Signal
Section 5.2.3 Oscillator with a R-C filter
Section 5.2.4 Frequency tuning range of the VCO
Section 5.2.5 Transconductane of a signal MOS

Conclusion

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