此文提出一個低相位雜訊振盪電路，這電路完全實現於晶片上的電感電容壓控振盪器，我們是把台灣積體電路的0.25μm的CMOS（互補式金屬氧化物半導體）製程參數放入Advanced Design System（ADS）模擬軟體中模擬，在本文中我們介紹了一些電路技術和改善相位雜訊的方法。這個振盪電路具有一個10% 的調變頻率範圍，而相位雜訊是 -120.3dBc/Hz在1MHz的附近。在此電路架構中包含了電感、可變電容和正回授差動對。

　　　　　In this paper, we present a low phase-noise oscillator circuit. The circuit of an inductor-capacitor (LC) tank oscillator is made on the chip. The 0.25μm complementary metal-oxide-semiconductor (CMOS) process parameter of Taiwan Semiconductor Manufacturing Company (TSMC) are entered into Advanced Design System (ADS) software to simulate an LC tank oscillator circuit. Some circuit technology and an improved method for phasing noise are introduced. The oscillator circuit has a 10% tuning range, the phase noise of which is –120.3 dBc/Hz at a 1MHz frequency offset in industry-science-medicine (ISM) band. The circuit architecture includes inductors, varactors, and a positive-feedback differential pair.