Tunable active inductor based VCO and BPF in a single integrated design for wireless applications in 90 nm CMOS process

Abstract

Abstract This article proposes a tunable active inductor (AI)‐based voltage‐controlled oscillator (VCO) andbandpass filters (BPF) on a single integrated design in 90 nm CMOS process for wireless applications. By exploiting component sharing technique through single pole double throws switching method, a common AI is shared between VCO and BPFs. As the passive inductor is replaced by the AI and shared, silicon area consumption is significantly reduced. Transforming the inductor in tunable mode benefits to eliminate MOS varactors for tuning purposes; one step forward to reduce silicon area consumption. Operating as VCO, its frequency ranges from 1.93 to 6.22 GHz (tuning scope is 105%) for tuning voltage of 0.2 ∼ 1 V. The DC power consumption varies from 1.83 to 3.84 mW, and differential output power is 3.39 to − 2.99 dBm. The phase noise varies from − 81.32 to − 76.89 dBc/Hz, and the figure of merit has a value of − 148.74 dBc/Hz at 5.03 GHz frequency. While acting as BPF, two approaches of center frequency tuning are applied. The voltage tuning yields center frequency of 8.43 ∼ 7.08 GHz along with the maximum gain of 10.29 dB at 7.81 GHz. The capacitive tuning outputs frequency tuning of 7.64 ∼ 7.06 GHz. The BPF consumes DC power of 2.56 to 2.27 mW (voltage tuning) and 2.40 mW (capacitive tuning). The proposed design occupies a layout area of 1215.6 μm2. All the simulations have been performed considering parasitic elements evolved from the extraction of layout. Finally, a quantitative comparison and justification of the proposed design are made with respect to other published works.

Keywords

• active inductor
• BPF
• DC power consumption
• frequency
• phase noise
• VCO