Current Noise of Chopper Amplifiers

  • Jiawei Xu
  • Refet Firat Yazicioglu
  • Chris Van Hoof
  • Kofi Makinwa
Part of the Analog Circuits and Signal Processing book series (ACSP)


This chapter investigates the root cause of 1/f2 noise of chopper amplifiers through a theoretical analysis and measurements of several chopper IAs. It is well known that the charge injection and clock feedthrough associated with the MOSFETs of the input chopper give rise to significant input current and current noise, which may then be a significant contributor to the amplifier’s total input-referred voltage noise. Furthermore, the chopper noise has a white power spectral density, its magnitude is roughly proportional to the chopping frequency. Design guidelines are proposed to reduce the chopper noise. A further proposal is the use of a clock-bootstrapped chopper, which exhibits less noise than a traditional chopper.


1/f2 noise Charge injection Clock feedthrough Current noise 


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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • Jiawei Xu
    • 1
  • Refet Firat Yazicioglu
    • 2
  • Chris Van Hoof
    • 3
  • Kofi Makinwa
    • 4
  1. 1.Holst Centre / imecEindhovenThe Netherlands
  2. 2.Galvani BioelectronicsStevenageUK
  3. 3.ESAT-MICASKU Leuven / imecLeuvenBelgium
  4. 4.Delft University of TechnologyDelftThe Netherlands

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