The Design of Narrowband CMOS RF Low-Noise Amplifiers

  • Thomas H. Lee


General conditions for minimizing the noise figure of any linear two-port are reviewed before considering the specific case of a MOSFET low-noise amplifier (LNA). It is shown that the minimum noise figure cannot be obtained over an arbitrarily large bandwidth with networks of low order. For narrowband operation, however, one may construct simple amplifiers whose noise figure and power gain are close to the theoretical optima allowed within an explicit power constraint, and which simultaneously present a specified impedance to the driving source. The effects of overlap (drain-gate) capacitance, short-channel carrier heating, substrate resistance (“epi noise”), and gate interconnect resistance are also considered. Amplifier noise figures of 1.5dB or better at 10mW are achievable in the 1–2GHz range with 0.5μm technology, and improve with scaling.


Noise Figure Noise Factor Input Admittance Minimum Noise Figure Gate Noise 
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  1. [1]
    T. Lee, The Design of CMOS Radio-Frequency Integrated Circuits, Chapter 10, Cambridge University Press, 1998.Google Scholar
  2. [2]
    R. Jindal, “Distributed Substrate Resistance Noise in Fine-Line NMOS Field-Effect Transistors,” IEEE Trans, on Electron Devices, vol. ED-32, no. 11, Nov. 1985, pp. 2450–2453.CrossRefGoogle Scholar
  3. [3]
    D. Shaeffer and T. Lee, “A 1.5V, 1.5GHz CMOS Low Noise Amplifier,” IEEEJ. Solid-State Circuits, vol. 32, no. 5, May, 1997, pp. 745–759.CrossRefGoogle Scholar
  4. [4]
    G. Brenna, “LNA Research,” Diploma Thesis, École Polytechnique Fédérale de Lausanne, Feb. 1998.Google Scholar
  5. [5]
    D. Shaeffer et al., “A 115mW CMOS GPS Receiver,” ISSCC Digest of Technical Papers, Feb. 1998.Google Scholar

Copyright information

© Springer Science+Business Media Dordrecht 1999

Authors and Affiliations

  • Thomas H. Lee
    • 1
  1. 1.Stanford University Center for Integrated SystemsStanfordUSA

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