A nonlinear adaptive filter for sensor and amplifier linearization

This paper presents a new nonlinear filter topology to digitally compensate externally linear, internally nonlinear analog circuits. The proposed methodology is based on nonlinear adaptive digital filters, able to linearize not only the sensor VxI characteristics, but the amplifier and anti-alias filter as well. One of the main goals of this methodology is the performance increase of analog circuits built with digital CMOS technology, specifically in gate-arrays and other semi-custom approaches. This paper presents the basic theory, and two different nonlinear filter topologies are compared. Prototype results validate the proposed method