Roermund, "A low-voltage ultra-low-power translinear integrator for audio fiiter applications

Abstract—In this paper, the design and measurement of a 1-V translinear integrator and its application in a controllable second-order lowpass filter for hearing instruments is presented. A semicustom version of the filter has been integrated in a standard 2-m, 7-GHz, bipolar IC process and operates at voltages down to 1 V, consumes only 6 A, and has a dynamic range of 57 dB for a total harmonic distortion below 2%. Its cutoff frequency is linearly adjustable in octaves from 1.6 to 8 kHz. Index Terms—Active filters, bipolar analog integrated circuits, current mode, low power, low voltage. I