FBDDA AMPLIFIER AND DEVICE INCLUDING THE FBDDA AMPLIFIER

摘要

A FBDDA amplifier comprising: a first differential input stage, which receives an input voltage; a second differential input stage, which receives a common-mode voltage; a first resistive-degeneration group coupled to the first differential input; a second resistive-degeneration group coupled to the second differential input; a differential output stage, generating an output voltage; a first switch coupled in parallel to the first resistive-degeneration group; and a second switch coupled in parallel to the second resistive-degeneration group. The first and second switches are driven into the closed state when the voltage input assumes a first value such that said first input stage operates in the linear region, and are driven into the open state when the voltage input assumes a second value, higher than the first value, such that the first input stage operates in a non-linear region.

主权项

1. A FBDDA amplifier, comprising:
a first differential input stage, configured to receive an input voltage signal, including an a.c. component and a d.c. component; a second differential input stage, configured to receive a d.c. common-mode voltage signal, said d.c. component of the input signal being said common-mode voltage signal; a first resistive-degeneration group coupled to the first differential input stage; a second resistive-degeneration group coupled to the second differential input stage; and a differential output stage, configured to supply an output voltage signal, a first switch coupled in parallel to the first resistive-degeneration group; and a second switch coupled in parallel to the second resistive-degeneration group; wherein said first and second switches being in a closed state, thus bypassing the first and second resistive-degeneration groups, during a first operating condition where said input voltage signal has a first value, and being in an open state during a second operating condition where said input voltage signal has a second value, higher than the first value, thus reducing a harmonic distortion of the output voltage signal.