학술논문
A 1024-Channel 10-Bit 36-$\mu$W/ch CMOS ROIC for Multiplexed GFET-Only Sensor Arrays in Brain Mapping
Document Type
Periodical
Author
Source
IEEE Transactions on Biomedical Circuits and Systems IEEE Trans. Biomed. Circuits Syst. Biomedical Circuits and Systems, IEEE Transactions on. 15(5):860-876 Oct, 2021
Subject
Language
ISSN
1932-4545
1940-9990
1940-9990
Abstract
This paper presents a 1024-channel neural read-out integrated circuit (ROIC) for solution-gated GFET sensing probes in massive $\mu$ECoG brain mapping. The proposed time-domain multiplexing of GFET-only arrays enables low-cost and scalable hybrid headstages. Low-power CMOS circuits are presented for the GFET analog frontend, including a CDS mechanism to improve preamplifier noise figures and 10-bit 10-kS/s A/D conversion. The 1024-channel ROIC has been fabricated in a standard 1.8-V 0.18-$\mu$m CMOS technology with 0.012 mm $^2$ and 36 $\mu$ W per channel. An automated methodology for the in-situ calibration of each GFET sensor is also proposed. Experimental ROIC tests are reported using a custom FPGA-based $\mu$ECoG headstage with $16\times 32$ and $32\times 32$ GFET probes in saline solution and agar substrate. Compared to state-of-art neural ROICs, this work achieves the largest scalability in hybrid platforms and it allows the recording of infra-slow neural signals.