A DC‐coupled 1.2 μW 0.012 mm ² per channel neural amplifiers array with 75 dB system common mode rejection ratio and 300 mV common mode interference

System common mode rejection ratio (SCMRR) and interference (CMI) range are two critical design specifications for multiple-channel neural recording front-end circuit in a freely moving animal experiment environment. This letter presents amplifiers array consisting of 15 DC-coupled inverter-based channels, reference channel shared voltage averaging (VAC) with floating rail Common Mode Feedback (CMFB) to achieve high SCMRR large CMI range. Meanwhile, power consumption area optimized through using simple inverter architecture removal the conventional on-chip AC-coupled capacitors. The proposed amplifier is implemented SMIC standard 0.18 μm CMOS process, achieving typical 75 dB (DC-80 Hz), 300 mV range, 1.2 μW 0.012 mm2 per channel. validated both by bench-top test in-vivo experiment.