摘要 |
Methods and circuits for extracting a true mean of two signals are provided. A first amplifier input stage (e.g., an n-type stage) is operated when a mean of the two signals approaches an upper rail voltage. A second amplifier input stage (e.g., a p-type stage) is operated when the mean of the two signals approaches a lower rail voltage. A transitioning circuit controls how much each of the first and the second amplifier input stages contributes to an input of a high-gain amplifier output stage, when the mean of the two signal does not approach either of the rail voltages. An output of the high-gain amplifier output stage is fed back to both the first and second amplifier input stages via a feedback stage, which can be a matched buffer stage.
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