Abstract

We have developed an amplifier which removes its "offset" as a natural part of its operation by modifying the charge on a floating gate. The charge on the floating gate is adapted by a combination of electron tunneling and hot-electron injection, resulting in a nonlinear high-pass filter with a cutoff frequency less than 1 Hz. We show experimental data from this autozeroing amplifier for various input waveforms, and an analytical model which fits the output waveforms. This autozeroing amplifier is a single-input case of a continuous learning circuit. 1. INTRODUCTION We have developed an amplifier which removes its "offsets" as a natural part of its operation by modifying the charge on a floating gate. Offsets, including drifts due to temperature, are often a difficult problem in designing analog circuits, and it is desirable if not essential to eliminate them. Previous autozeroing techniques have relied on clocking schemes which periodically compute the offset and then subtract it fro...

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