论文信息 - A 3.9μW, 81.3dB SNDR, DC-coupled, Time-based Neural Recording IC with Degeneration R-DAC for Bidirectional Neural Interface in 180nm CMOS

A 3.9μW, 81.3dB SNDR, DC-coupled, Time-based Neural Recording IC with Degeneration R-DAC for Bidirectional Neural Interface in 180nm CMOS

This paper presents a 5-bit VCO-based neural recording IC, which directly quantizes the input signal and achieves a large dynamic range (DR) to process the small-amplitude neural signal in the presence of the large-amplitude stimulation artifact (SA). A feedback-controlled source degeneration is applied to the input transconductor circuit (Gm,in) by using a resistor DAC (R-DAC). It mitigates the circuit nonlinearity, resulting in a large signal-to-noise-and-distortion ratio (SNDR) and a high input impedance (Zin). The implemented neural recording IC achieves 813dB SNDR over 200Hz signal bandwidth and 200mVPP maximum allowable input range while consuming 3.9μW per channel.

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