TY - GEN
T1 - A 99.5dB-DR 5kHz-BW Closed-Loop Neural-Recording IC based on Continuous-Time Dynamic-Zoom ΔΣ ADC with Automatic AFE-Gain Control
AU - Jung, Yoontae
AU - Kweon, Soon Jae
AU - Jeon, Hyuntak
AU - Lee, Taeju
AU - Choi, Injun
AU - Jeong, Kyeongwon
AU - Kim, Mi Kyung
AU - Lee, Hyunjoo Jenny
AU - Ha, Sohmyung
AU - Je, Minkyu
N1 - Publisher Copyright:
© 2021 IEEE.
PY - 2021
Y1 - 2021
N2 - Neural-recording ICs have been a key tool to unravel the mystery of the human brain and find treatments for various neurological diseases. Since neural signals inherently have a small amplitude and suffer from environmental interferences, conventional neural recording circuits have been mainly designed for low noise, high CMRR, and low power, using the structure with a high-gain amplifier and a low-resolution ADC [1] (Fig. 1). With the advent of closed-loop neurotherapeutics, stimulation artifacts have been a notorious obstacle in neural recording. To tackle this issue, a direct-conversion structure has been widely used due to its wide dynamic range [3] -[7]. However, the structure could not meet the bandwidth (BW) requirement of 5kHz and the input-referred noise (IRN) requirement of 7 \mu V{rms} simultaneously. In this paper, we present a closed-loop neural-recording IC using an adaptive automatic gain controller (AGC) and continuous-time dynamic-zoom \Delta \Sigma ADC (CT-Zoom-ADC). By combining the AGC and CT-Zoom-ADC, the IRN performance is improved to 6.1 \mu V{rms} at 5kHz BW, and the saturation issue of the conventional amplifier-based recording structure is alleviated. Also, the recording IC can rapidly recover the signal from transient artifacts thanks to the digital auto-ranging block (DAR).
AB - Neural-recording ICs have been a key tool to unravel the mystery of the human brain and find treatments for various neurological diseases. Since neural signals inherently have a small amplitude and suffer from environmental interferences, conventional neural recording circuits have been mainly designed for low noise, high CMRR, and low power, using the structure with a high-gain amplifier and a low-resolution ADC [1] (Fig. 1). With the advent of closed-loop neurotherapeutics, stimulation artifacts have been a notorious obstacle in neural recording. To tackle this issue, a direct-conversion structure has been widely used due to its wide dynamic range [3] -[7]. However, the structure could not meet the bandwidth (BW) requirement of 5kHz and the input-referred noise (IRN) requirement of 7 \mu V{rms} simultaneously. In this paper, we present a closed-loop neural-recording IC using an adaptive automatic gain controller (AGC) and continuous-time dynamic-zoom \Delta \Sigma ADC (CT-Zoom-ADC). By combining the AGC and CT-Zoom-ADC, the IRN performance is improved to 6.1 \mu V{rms} at 5kHz BW, and the saturation issue of the conventional amplifier-based recording structure is alleviated. Also, the recording IC can rapidly recover the signal from transient artifacts thanks to the digital auto-ranging block (DAR).
UR - http://www.scopus.com/inward/record.url?scp=85123993024&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85123993024&partnerID=8YFLogxK
U2 - 10.1109/A-SSCC53895.2021.9634824
DO - 10.1109/A-SSCC53895.2021.9634824
M3 - Conference contribution
AN - SCOPUS:85123993024
T3 - Proceedings - A-SSCC 2021: IEEE Asian Solid-State Circuits Conference
BT - Proceedings - A-SSCC 2021
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2021 IEEE Asian Solid-State Circuits Conference, A-SSCC 2021
Y2 - 7 November 2021 through 10 November 2021
ER -