A wideband balun-LNA employing g m-boosting with improved gain balance

作者：Ma, Li; Wang, Zhigong^*; Xu, Jian

来源：Analog Integrated Circuits and Signal Processing, 2016, 86(1): 3-9.

DOI：10.1007/s10470-015-0649-1

• Low noise amplifier (LNA)
• Balun
• Single-to-differential
• g(m)-Boosting
• Composite transistor
• Gain balance

A wideband single-ended input and differential output low noise amplifier (LNA) employing the common-gate (CG) common-source (CS) structure is presented. The output of the CS transistor is utilized to boost the effective transconductance of the CG stage. The gain balance won't be affected by the g (m)-boosting stage, because its gain is constant, and independent of process, voltage, and temperature. The composite CS stage, consisting of two parts, is first proposed to cancel the gain imbalance induced by the back-gate effect. The first part of the CS transistors employs the body-coupling technique, and the other part are the conventional CS transistors. For a proof-of-concept, the proposed balun-LNA is fabricated in a 0.13 mu m CMOS process. The frequency band of the circuit is 0.5-3.7 GHz. The measured in-band average and maximum gain imbalance are 0.34, 0.7 dB, respectively. The phase imbalance range is -1A degrees to 5A degrees. A noise figure of 3.7-6.2 dB, and a minimum IIP3 of -7.1 dBm are obtained. Good input/output matching are achieved through the frequency band. The LNA consumes a power of 10.2 mW from a 1.5 V supply.

• 单位
  东南大学