Microelectrode arrays (MEA) are widely used to record extracellular action potential (AP) and local field potential (LFP) in electro-psychological studies. Conventional MEA detectors have low linearity (1%) and limited dynamic range (DR<70dB). New immunological applications such as mast cell recoding require higher linearity and wider DR. In this paper, we introduce a new MEA detector architecture with a continuous-time (CT) front-end and a discrete-time (DT) back-end to achieve high linearity. We also use chopping and anti-aliasing RC filter to reduce the noise in the CT front-end and the DT back-end respectively so as to achieve wide DR. The new detector is implemented in a 0.35µm CMOS process. SPICE simulation shows that it achieves 0.07% linearity for 20mVpp input signal and 0.6µVrms input-referred noise over 1–200Hz for the LFP signal which results in 81.4dB DR. It can also record the AP signal with 66dB DR. The power consumption is 66.5µW from a 3.3V supply.
[1]
Reid R. Harrison,et al.
A Versatile Integrated Circuit for the Acquisition of Biopotentials
,
2007,
2007 IEEE Custom Integrated Circuits Conference.
[2]
R. R. Harrison,et al.
A low-power low-noise CMOS amplifier for neural recording applications
,
2003,
IEEE J. Solid State Circuits.
[3]
Jessica Ka-Yan Law,et al.
The use of microelectrode array (MEA) to study rat peritoneal mast cell activation.
,
2008,
Journal of pharmacological sciences.
[4]
Refet Firat Yazicioglu,et al.
A 200 $\mu$ W Eight-Channel EEG Acquisition ASIC for Ambulatory EEG Systems
,
2008,
IEEE Journal of Solid-State Circuits.
[5]
J. H. Fischer.
Noise sources and calculation techniques for switched capacitor filters
,
1982
.