Frequency Domain Modeling and Performance Analysis of Injection-Locked LC Oscillator

• Published in: IEEE transactions on circuits and systems. II, Express briefs Express briefs, 2024-01, Vol.71 (1), p.1-1
• Main Authors: Xin, Kewei, Lai, Mingche, Lv, Fangxu, Zheng, Xuqiang, Guo, Kaile, Pang, Zhengbin, Xu, Chaolong, Zhang, Geng, Wang, Wenchen, Li, Meng
• Format: Article
• Language: English
• Subjects: Analytical models; Circuit design; Clock generators; Design optimization; Frequency domain analysis; Frequency locking; Impulse sensitivity function (ISF); injection factor; injection-locked LC oscillator; Injection-locked oscillators; Integrated circuit modeling; Mathematical models; Oscillators; Phase locked loops; Phase noise; Pulse duration; track bandwidth
• ISSN: 1549-7747; 1558-3791
• DOI: 10.1109/TCSII.2023.3296778

This paper proposes a frequency domain model for injection-locked LC oscillators by introducing the impulse sensitivity function (ISF) and injection factor, analyzes the effect of the injection pulse width and injection position on oscillator performance based on this model, and derives an equation that can guide the design and optimization of oscillators. The model fills the gap in the field of frequency domain models for injection-locked LC oscillators. Based on the above model, a clock generator circuit structure operating at 14 GHz, combining a phase-locked loop with an injection-locked oscillator, is designed and measured based on a 65-nm cmos process. The circuit achieves better phase noise performance by optimizing the two parameters, which verifies the accuracy of the proposed model.