Stimulation and Artifact-Suppression Techniques for In Vitro High-Density Microelectrode Array Systems
Open accessAbstract
We present novel voltage stimulation buffers with controlled output current, along with recording circuits featuring adjustable high-pass cut-off filtering to perform efficient stimulation while actively suppressing stimulation artifacts in high-density microelectrode arrays. Owing to the dense packing and close proximity of the electrodes in such systems, a stimulation through one electrode can cause large electrical artifacts on neighboring electrodes that easily saturate the corresponding recording amplifiers. To suppress such artifacts, the high-pass corner frequencies of all available 2048 recording channels can be raised from several Hz to several kHz by applying a "soft-reset" or pole-shifting technique. With the implemented artifact suppression technique, the saturation time of the recording circuits, connected to electrodes in immediate vicinity to the stimulation site, could be reduced to less than 150 μs. For the stimulation buffer, we developed a circuit, which can operate in two modes: either control of only the stimulation voltage or control of current and voltage during stimulation. The voltage-only controlled mode employs a local common-mode feedback operational transconductance amplifier with a near rail-to-rail input/output range, suitable for driving high-capacitive loads. The current/voltage controlled mode is based on a positive current conveyor generating adjustable output currents, whereas its upper and lower output voltages are limited by two feedback loops. The current/voltage controlled circuit can generate stimulation pulses up to 30 μA with less than ±0.1% linearity error in the low-current mode and up to 300 μA with less than ±0.2% linearity error in the high-current mode.
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Pole shifting helps to suppress stimulus artifacts by adjusting the amplifier's frequency response with limited switching artifacts that are typically caused by alternative front-end recovery methods.
“This method helps to suppress stimulus artifacts by adjusting the amplifier's frequency response with limited switching artifacts that are typically caused by alternative front-end recovery methods [190], such as amplifier charge reset and active electrode discharge.”
From Active Neural Interface Circuits and Systems for Selective Control of Peripheral Nerves: A Review (2024) · cites this paper as [190]
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- Authors
- Shadmani, A., Viswam, V., Chen, Y., Bounik, R., Dragas, J., Radivojevic, M., Geissler, S., Sitnikov, S., Muller, J., & Hierlemann, A.
- Affiliations
- ETH Zurich (CH)
- ORCID
- Venue
- IEEE Transactions on Biomedical Engineering
- Published
- 2019-09
- Volume
- 66
- Issue
- 9
- Pages
- 2481-2490
- ISSN
- 0018-9294 (ISSN-L)
- 1558-2531
- PMC
- PMC6711758
- OpenAlex
- W2907874759
- Cited by
- 24
- References
- 47
- Citations by year
- 2025: 7 · 2024: 4 · 2023: 1 · 2022: 2 · 2021: 6 · 2020: 4
- FWCI
- 1.06
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Licence
- Locations
- IEEE Transactions on Biomedical Engineering (publishedVersion)
- PubMed (publishedVersion)
- PubMed Central (acceptedVersion)
- Funders
- ERC Advanced Grants (NeuroCMOS / AdG 267351, neuroXscales / AdG 694829)
- FP7-MTN (EngCaBra / 264417)
- Schweizerischer Nationalfonds zur Furderung der Wissenschaftlichen Forschung (205321_157092/1, MHV-Grant 171267)
- Topics
- Physical Sciences › Engineering › Biomedical Engineering › Analog and Mixed-Signal Circuit Design
- Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neuroscience and Neural Engineering
- Physical Sciences › Engineering › Electrical and Electronic Engineering › Advanced MEMS and NEMS Technologies
- Keywords
- high-density microelectrode arrays, electrical stimulation, stimulation artifacts, artifact removal, high-pass filtering, pole shifting, operational transconductance amplifier, current conveyor
- MeSH terms
- Superconductivity, Animals, Electric Stimulation, Electrophysiology, Equipment Design, Microelectrodes, Neurons, Signal Processing, Computer-Assisted, Artifacts, Rats, Wistar, Rats
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