Electromagnetic Interference Resisting Operational Amplifier

This work proposes a robust electromagnetic interference (EMI) analog operational amplifier (OpAmp) based on a source-buffered differential pair. The proposed EMI performance has been verified via a test integrated circuit (IC) fabricated in NCSU 0.5 μm CMOS technology. Experimental results are presented when an EMI disturbance signal of 800 mV amplitude is injected at the input terminals and are then compared with the conventional and source-buffered topologies. The maximum EMI-induced input offset voltage corresponds to -222 mV for the proposed structure compared to a -712 mV input for a conventional one and -368 mV for a source-buffered one.