Patent ID: 7573327

Claim:
An instrumentation amplifier comprising: a first amplification sub-circuit comprising: a first input stage for sensing a differential input and generating a first intermediate current based thereon; a first feedback stage coupled with said first input stage, said first feedback stage for generating a first feedback current based on an output voltage of said instrumentation amplifier; and a first auto-zeroing circuit coupled with said first input stage and said first feedback stage, said first auto-zeroing circuit for generating a first nulling current, wherein said first nulling current compensates for first errors in said first intermediate current and said first feedback current resulting from first input offsets in said first input stage and said first feedback stage; a second amplification sub-circuit coupled to said first amplification sub-circuit, said second amplification sub-circuit comprising: a second input stage for sensing said differential input and generating a second intermediate current based thereon; a second feedback stage coupled with second first input stage, said second feedback stage for generating a second feedback current based on said output voltage of said instrumentation amplifier; and a second auto-zeroing circuit coupled with said second input stage and said second feedback stage said second auto-zeroing circuit for generating a second nulling current, wherein said second nulling current compensates for second errors in said second intermediate current and said second feedback current resulting from second input offsets in said second input stage and said second feedback stage; and an output stage coupled with said first and second amplification sub-circuits, said output stage for generating said output voltage; wherein said first and second amplification sub-circuits further comprise a switching circuit for switching said instrumentation amplifier between a first configuration and a second configuration, wherein, in said first configuration, said first amplification sub-circuit provides a first amplification path for said instrumentation amplifier, and wherein further, in said second configuration, said second amplification sub-circuit provides a second amplification path for said instrumentation amplifier.