A 6–9 GHz UWB balun-LNA employing current-reuse with preamplifier and CCC buffer

• DOI: 10.1007/s10470-014-0255-7
• Publication Date: 2014-01-18T18:03:28Z
• Authors: Zhi Li; Liguo Sun; Lu Huang
• Keywords: Balun; Preamplifier; Wideband; Common gate; Return loss

This paper presents a high-gain and low-power balun-LNA for ultra-wideband receiver operating in the upper band (6–9 GHz). Common gate (CG) preamplifier in front of the active balun can provide input matching and suppress noise from the follow-up stages. Active balun shares bias current with the CG stage to reduce power consumption. Capacitor-cross-coupled buffer is cascaded for signal amplitude and phase correction. The balun-LNA is fabricated in TSMC 130 nm CMOS technology and it consumes 5.5 mA current from a 1.3-V supply including buffer. This balun-LNA can achieve wideband gain from 6.5 to 9.0 GHz and the maximum gain is 23 dB. The input return loss is better than 20 dB from 6.5 to 9.0 GHz. The core area of the LNA is 0.53 mm2. Simulated noise figure of the LNA is under 3.2 dB.