Variable inductance planar spiral inductors and CMOS wideband amplifiers with inductive peaking

✍ Scribed by Yo-Sheng Lin; Jia-Lun Chen; Ke-Hou Chen

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 275 KB
• Volume: 47
• Category: Article
• ISSN: 0895-2477
• DOI: 10.1002/mop.21153

✦ Synopsis

In this paper, a complete set of variable inductance (VI) planar spiral inductors with MOSFET switches are characterized and modeled for the first time. These VI inductors can be used to optimize the performances of CMOS wideband low-noise amplifiers (LNAs) with inductive peaking, to implement low-phase noise voltage-controlled oscillators (VCOs), and so on. Moreover, the experimental results show that series-inductive peaking can effectively improve the bandwidth of the CMOS wideband LNAs. For a CMOS wideband LNA with a 0.58-nH peaking inductor, a 74.2% (from 3.1 to 5.4 GHz) increase in bandwidth is achieved. The measured noise figures (NFs) are 2.2 dB at 1 GHz and 4.0 dB at 6 GHz. The measured input 3 rd -order intercepting point ( IIP3) is Ϫ3 dBm at 3 GHz. These results show that the performances of CMOS wideband LNAs can be improved by inductive peaking, which can be optimized by our developed VI inductors.