To satisfy the requirements for multi-standard frequency generation, mode-switching oscillators are developed to increase the frequency tuning range without incurring considerable phase noise penalty. However, this improvement in the tuning range is often limited by the parasitics of the circuitry for mode selection and tuning. To address this challenge, this work presents a dual-core octave-tuning VCO using a switch-less tertiary magnetic coupling loop. The design employs the benefits of transformer-switching without incurring switch loss and quality factor degradation and also the benefits of mode switching without the parasitics from the mode selection and tuning network. The VCO employs a non-constant $RC$ scaling for the capacitors’ bank, across the tuning bits, and positive feedback dc-coupled inductive-degenerated output buffer to maximize the tuning range. Implemented in 22 nm fully depleted silicon-on-insulator (FDSOI), the dual-core VCO achieves a 72% tuning at 8–17 GHz and a figure-of-merit-tuning ( $\text {FoM}_{T}$ ) of 208.8 dBc/Hz at 11 GHz. The chip operates from a 0.45 V supply with a power consumption of 17–33 mW and a core area of 0.39 mm ² . To the best of our knowledge, the VCO achieves the highest $\text {FoM}_{T}$ and lowest supply for designs over 10 GHz.

中文翻译：

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利用三模式开关量少的三次磁环，倍频调谐双核折叠式VCO

为了满足多标准频率生成的要求，开发了模式切换振荡器以增加频率调谐范围，而不会引起相当大的相位噪声损失。但是，调谐范围的这种改善通常受到模式选择和调谐电路的寄生因素的限制。为了应对这一挑战，这项工作提出了一种使用无开关三次磁耦合环路的双核倍频程调谐VCO。该设计利用了变压器切换的好处，而不会引起开关损耗和品质因数的降低，并且还利用了模式切换的好处，而没有来自模式选择和调谐网络的寄生效应。VCO使用非常量 $ RC $ 在整个调谐位上缩放电容器组的大小，并通过正反馈直流耦合电感退化的输出缓冲器来最大程度地提高调谐范围。双核VCO采用22 nm全耗尽型绝缘体上硅（FDSOI）实施，在8–17 GHz频率下实现了72％的调谐，并且具有优异的调谐系数（ $ \ text {FoM} _ {T} $ 在11 GHz时为208.8 dBc / Hz）。该芯片采用0.45 V电源供电，功耗为17-33 mW，核心面积为0.39 mm ² 。据我们所知，VCO达到了最高 $ \ text {FoM} _ {T} $ 10 GHz以上设计的最低电源。