Programmable chopping architecture to reduce offset in an analog front end

A method comprising:

• receiving a first analog input signal at an input;
• by operation of an amplifier, amplifying the first analog input signal;
• filtering a first output of the amplifier with a programmable anti-aliasing filter (AAF), the first output corresponding to the first analog input signal;
• modulating a first output of programmable AAF with a modulator into a first portion of a digital data stream;
• receiving a second analog input signal at the input;
• by operation of the amplifier, amplifying the second analog input signs signal;
• bypassing filtering a second output of the amplifier with the programmable AAF, the second output corresponding to the second analog input signal;
• modulating a second output of the programmable AAF with the modulator into a second portion of the digital data stream;
• and
• chopping analog signals at locations between the input and the modulator with one or more chopping circuits.

A system comprising:

• an analog front end (AFE) that comprises:
• an amplifier coupled to receive an analog input signal;
• a programmable anti-aliasing filter (AAF) coupled to an output of the amplifier;
• a modulator to generate a digital data stream in response to the analog input signal;
• and
• one or more chopping circuits, wherein the programmable AAF comprises:
• a first path between the amplifier and the modulator with an input resistance;
• and
• a second path between the amplifier and the modulator that bypasses the input resistance;
• and
• at least one sensor configured to generate the analog input signal.