ABSTRACT A wideband voltage-controlled oscillator (VCO) with coupling reduction and small VCO gain ( ) variation has been fabricated for multi-standard RF transceivers. A high-quality factor 8-shaped inductor is adopted to reduce the magnetic coupling between inductors and optimise the phase noise of the VCO. Electromagnetic simulations of magnetic coupling are carried out between an octagonal inductor and an 8-shaped inductor, and as high as 36 dB reduction in magnetic coupling is achieved by using 8-shaped inductors. A novel varactor group is proposed to realise a constant in the fine-tuning process, in which the scheme adopts an inversion-mode MOS varactor to revise the capacitance variation of an accumulation-mode MOS varactor. Meanwhile, an extra 3-bit varactor array is employed to reduce variation in the coarse tuning process. Based on a conventional TSMC 0.18-μm CMOS process, a nearly constant of 58 MHz/V is obtained for a wide frequency range of 4.02 to 5.48 GHz. The proposed VCO achieves a phase noise of less than −119.8 dBc/Hz at 1 MHz offset. The current consumption is 4.3–8.8 mA under a source voltage of 1.8 V.

中文翻译：

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4.02-5.48 GHz 宽带 VCO，具有耦合降低和小 Kvco 变化

摘要 已为多标准 RF 收发器制造了具有耦合减少和小 VCO 增益 ( ) 变化的宽带压控振荡器 (VCO)。采用高品质因数8字形电感，降低电感之间的磁耦合，优化VCO的相位噪声。在八角形电感器和8字形电感器之间进行磁耦合的电磁模拟，使用8字形电感器实现了高达36 dB的磁耦合降低。为了在微调过程中实现恒定，提出了一种新的变容二极管组，该方案采用反型MOS变容二极管来修正累积型MOS变容二极管的电容变化。同时，采用额外的 3 位变容器阵列来减少粗调过程中的变化。基于传统的 TSMC 0.18-μm CMOS 工艺，在 4.02 至 5.48 GHz 的宽频率范围内获得了几乎恒定的 58 MHz/V。建议的 VCO 在 1 MHz 偏移下实现小于 −119.8 dBc/Hz 的相位噪声。在 1.8 V 的电源电压下，电流消耗为 4.3–8.8 mA。