A Low-Power Wide-Linear-Range Transconductance Amplifier

  • Rahul Sarpeshkar
  • Richard F. Lyon
  • Carver Mead
Part of the The Springer International Series in Engineering and Computer Science book series (SECS, volume 447)


In the past few years, engineers have improved the linearity of MOS transconductor circuits [2, 5, 10, 11, 19, 20, 26, 28, 29, 32]. These advances have been primarily in the area of above-threshold, high-power, high-frequency, continuous-time filters. Although it is possible to implement auditory filters (20Hz-20khz) with these techniques, it is inefficient to do so. The transconductance and current levels in above-threshold operation are so high that large capacitances or transistors with very low W/L are required to create low-frequency poles, and area and power are wasted. In addition, it is difficult to span 3 orders of magnitude of transconductance with a square law, unless we use transistors with ungainly aspect ratios. However, it is easy to obtain a wide linear range above threshold.


Bias Current Corner Frequency Bipolar Transistor Total Harmonic Distortion Wide Linear Range 


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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • Rahul Sarpeshkar
    • 1
  • Richard F. Lyon
    • 2
  • Carver Mead
    • 3
  1. 1.Department of Biological ComputationBell LaboratoriesMurray Hill
  2. 2.Foveonics Inc.Cupertino
  3. 3.Physics of Computation LaboratoryCalifornia Institute of TechnologyUSA

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