A low-noise fully-differential neural recording CMOS preamplifier for applications

• Published in: 中国科学：信息科学（英文版） 2012, Vol.55 (2), p.441-452
• Main Author: ZHANG Xu PEI WeiHua HUANG BeiJu GUAN Ning CHEN HongDa
• Format: Article
• Language: English
• Subjects: CMOS; 互补金属氧化物半导体; 低噪声; 全差分; 前置放大器; 应用; 录制; 神经
• ISSN: 1674-733X; 1869-1919

A fully-differential bandpass CMOS preamplifier for extracellular neural recording is presented in this paper. The capacitive-coupled and capacitive-feedback topology is adopted. We describe the main noise sources of the proposed preamplifier and discuss the methods for achieving the lowest input-referred noise. The preamplifier has a midband gain of 43 dB and a DC gain of 0. The -3 dB upper cut-off frequency of the preamplifier is 6.8 kHz. The lower cut-off frequency can be adjusted for amplifying the field or action potentials located in different bands. It has an input-referred noise of 3.36 ~Vrms integrated from 1 Hz to 6.8 kHz for recording the local field potentials （LFPs） and the mixed neural spikes with a power dissipation of 24.75 μW from 3.3 V supply. When the passband is configured as 100 Hz-6.8 kHz for only recording spikes, the noise is measured to be 3.01μVrms. The 0.115 mm2 prototype chip is designed and fabricated in 0.35μm Nbwell CMOS （complementary metal oxide semiconductor） 2P4M process.