A low-power active inductor with improved Q-factor and its application to phase shifter

作者：Li Chaojiang^*; Wang Pingshan; Gong Fei

来源：Analog Integrated Circuits and Signal Processing, 2011, 66(2): 303-307.

DOI：10.1007/s10470-010-9553-x

• Active inductor
• Feedback
• High Q-factor
• Low power
• Phase shifter

This letter presents a low-power single-ended active inductor with its Q-factor enhanced by feedback. Without sacrificing the self-resonance frequency and increasing the DC power consumption of the main circuit, the feedback transistor introduces a negative resistance; therefore, high Q-factors can be achieved in a wide operating frequency range. The proposed inductor was designed in a 0.13 mu m CMOS process and simulated using Cadence Spectre. The active area is similar to 4 mu m x 5 mu m. With similar to 0.1 mW power consumption, the designed active inductor shows a 17 GHz maximum self-resonance frequency and a 1-8 GHz peak-Qoperating frequency range. Using this active inductor, a 3-bit digitally-controlled phase shifter was designed. The phase shifter can provide a phase shift range larger than 180 degrees from 1.5 to 4 GHz and a return loss better than 10 dB.

• 出版日期2011-2