An instrumentation amplifier input circuit with a high immunity to EMI

This paper presents an instrumentation amplifier input circuit exhibiting a high degree of immunity against conducted common-mode electromagnetic interferences (EMI) which are injected into its inputs. The proposed input circuit achieves a high common-mode EMI rejection by minimizing the impact of mismatch. A case study illustrates the theoretical analyses, and evaluates the superior performances of the proposed input structure by comparing these to the results which are obtained using a classic approach. © 2008 IEEE.