Circuits, Systems, and Signal Processing

, Volume 35, Issue 4, pp 1377–1393 | Cite as

Switched-Capacitor Fractional-Step Butterworth Filter Design

  • C. Psychalinos
  • G. Tsirimokou
  • A. S. ElwakilEmail author
Short Paper


Switched-capacitor fractional-step filter design of low-pass filter prototypes with Butterworth characteristics is reported in this work for the first time. This is achieved using discrete-time integrators which implement both the bilinear and the Al-Alaoui s-to-z transformations. Filters of orders 1.2, 1.5 and 1.8 as well as 3.2, 3.5, and 3.8 are designed and verified using transistor-level simulations with Cadence on AMS \(0.35\,\upmu \)m CMOS process. Digital programmability of the fractional-step filters is also achieved.


Filter Design Circuit Complexity Filter Prototype Feedback Capacitor Realize Transfer Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported by Grant E.029 from the Research Committee of the University of Patras (Programme K. Karatheodori).


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Department of Physics, Electronics LaboratoryUniversity of PatrasPatrasGreece
  2. 2.Department of Electrical and Computer EngineeringUniversity of SharjahSharjahUnited Arab Emirates

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