A Low-Power Wide-Linear-Range Transconductance Amplifier

  • Authors:
  • Rahul Sarpeshkar;Richard F. Lyon;Carver Mead

  • Affiliations:
  • Physics of Computation Laboratory, California Institute of Technology, Pasadena, CA, 91125;Apple Computer, One Infinite Loop, Cupertino, CA 95014;Physics of Computation Laboratory, California Institute of Technology, Pasadena, CA, 91125

  • Venue:
  • Analog Integrated Circuits and Signal Processing
  • Year:
  • 1997

Quantified Score

Hi-index 0.00

Visualization

Abstract

The linear range of approximately ±75mV of traditional subthreshold transconductance amplifiers istoo small for certain applications—for example, for filtersin electronic cochleas, where it is desirable to handle loudsounds without distortion and to have a large dynamic range.We describe a transconductance amplifier designed for low-power(1/f,then an increase in its linear range has no effect on thefollower–integrator‘sdynamic range. To preserve follower–integrator bandwidth,power consumption increases proportionately with an increasein the amplifier‘s linear range. We also present data for changesin the subthreshold exponential parameter with current leveland with gate-to-bulk voltage that should be of interest to alllow-power designers. We have described the use of our amplifierin a silicon cochlea [1, 2].