Auto zero offset current mitigation at an integrator input

A system, comprising:

• an input stage configured to provide first and second input currents including respective measurement current components, at least one of the first input current or the second input current including an offset current component;
• an integrator having a first integrator input, a second integrator input, a first integrator output and a second integrator output, the integrator being configured to:
• receive the first input current at the first integrator input and the second input current at the second integrator input;
• integrate the first input current and the second input current;
• in response to integrating the first input current and the second input current, generate a first output voltage and a second output voltage;
• and
• output the first output voltage at the first integrator output and the second output voltage at the second integrator output;
• and
• a feedback stage including:
• a transconductance amplifier having a first feedback input selectively coupled to the first integrator output, a second feedback input selectively to the second integrator output, a first feedback output coupled to the first integrator input and a second feedback output coupled to the second integrator input, the transconductance amplifier being configured to:
• detect a difference between the first output voltage and the second output voltage;
• and
• sink or source a first output current at the first feedback output and a second output current at the second feedback output based on the difference between the first output voltage and the second output voltage, wherein the first output current is additively combined with the first input current and the second output current is additively combined with the second input current to mitigate the offset current component.

A method, comprising:

• receiving, by an integrator from an input stage, a first input current and a second input current, the first and second input currents including respective measurement current components, and at least one of the first input current or the second input current including an offset current component;
• integrating, by the integrator, the first input current and the second input current;
• generating, by the integrator, a first output voltage and a second output voltage;
• receiving, by a feedback stage including a transconductance amplifier, the first output voltage and the second output voltage;
• detecting, by the feedback stage, a difference between the first output voltage and the second output voltage;
• and
• sinking or sourcing, by the feedback stage, a first output current and a second output current based on the difference between the first output voltage and the second output voltage;
• and
• additively combining the first output current with the first input current and the second output current with the second input current to mitigate the offset current component at an input of the integrator.