Ku Chen-Chih, Wang Sen
Department of Electronic Engineering, National Taipei University of Technology, Taipei 10608, Taiwan.
Micromachines (Basel). 2025 Jun 5;16(6):682. doi: 10.3390/mi16060682.
This work proposes two voltage-controlled oscillators using noise-filtering technique. The first one is a 24-GHz voltage-controlled oscillator, and the second one is based on a push-push architecture with a λ/4 transmission line to further increase the frequency up to 48 GHz. The designs are implemented and verified in a standard 90-nm CMOS process. Typically, the current mirror transistor in the tail current has a nonlinear effect. When the transistor operates in the nonlinear region, noise will be introduced. Therefore, a set of LC filters with a resonant frequency at 2f0 are added to the design of this section to filter the noise at 2f0 through the capacitor to the ground. The measurement results show that the design of a single oscillator has an oscillation frequency of 24.37 GHz, a tuning range of 6.5%, and a phase noise of -97.19 dBc/Hz @1MHz. The measurement results of the push-push architecture show that the double oscillation frequency is 49.8 GHz, the tuning range is 7.2%, and the phase noise is -80.52 dBc/Hz @1MHz. The chip areas of 24-GHz LC VCO and 48-GHz push-push LC VCO are 0.68 mm × 0.69 mm and 0.7 mm × 0.7 mm, respectively.
这项工作提出了两种使用噪声滤波技术的压控振荡器。第一种是24GHz的压控振荡器，第二种基于带有λ/4传输线的推挽架构，以进一步将频率提高到48GHz。这些设计在标准90nm CMOS工艺中实现并得到验证。通常，尾电流中的电流镜晶体管具有非线性效应。当晶体管在非线性区域工作时，会引入噪声。因此，在该部分的设计中添加了一组谐振频率为2f0的LC滤波器，通过接地电容来滤除2f0处的噪声。测量结果表明，单个振荡器的设计振荡频率为24.37GHz，调谐范围为6.5%，在1MHz时的相位噪声为-97.19dBc/Hz。推挽架构的测量结果表明，双振荡频率为49.8GHz，调谐范围为7.2%，在1MHz时的相位噪声为-80.52dBc/Hz。24GHz LC VCO和48GHz推挽LC VCO的芯片面积分别为0.68mm×0.69mm和0.7mm×0.7mm。
