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.