Design of a folded cascode opamp with increased immunity to conducted electromagnetic interference in 0.18 μm CMOS

•Instrumentation amplifier input stage with an increased immunity to electromagnetic interference.•Measurements corroborating the simulations of this circuit.•Fundamental derivations of the proposed modified recycling cascode input stage.

This paper presents a folded cascode CMOS instrumentation amplifier input stage with an increased immunity to electromagnetic interference (EMI): this structure is based on a recycling folded cascode topology, and has been designed in a 0.18 μm UMC CMOS process. Measurements illustrate that the modified recycling folded cascode exhibits an increased EMI immunity while preserving a satisfactory frequency response.