设计了一种伪差分两级环形振荡器,可为锁相环提供8GHz四相位正交时钟。通过分析耦合两级环形振荡线性模型,对四级环形振荡结构进行优化,提出了伪差分两级环形振荡结构。基于单级缓冲器的开环分析,可对振荡器的输出频率进行精准估算,并判断振荡情况。采用65nm CMOS工艺进行设计与仿真。结果表明,在1.2V电压下,振荡器的功耗为6.9mW,1 MHz频率处的相位噪声为-82.104 5dB,满足高速SerDes接口的设计要求。 A pseudo-differential two-stage ring oscillator is designed to provide 8GHz quadrature phase quadrature clock for PLL. By analyzing the coupled two-stage linear oscillating linear model, the four-ring oscillating structure is optimized and a pseudo-differential two-stage ring oscillating structure is proposed. Based on the open-loop analysis of a single-stage buffer, the output frequency of the oscillator can be accurately estimated and the oscillation condition can be judged. 65nm CMOS process design and simulation. The results show that the oscillator consumes 6.9mW at 1.2V and the phase noise of -82.104 5dB at 1MHz meets the design requirements of high-speed SerDes interface.