eprintid: 10204210 rev_number: 6 eprint_status: archive userid: 699 dir: disk0/10/20/42/10 datestamp: 2025-02-03 12:17:05 lastmod: 2025-02-03 12:17:05 status_changed: 2025-02-03 12:17:05 type: article metadata_visibility: show sword_depositor: 699 creators_name: Habibollahi, Maryam creators_name: Jiang, Dai creators_name: Lancashire, Henry Thomas creators_name: Demosthenous, Andreas title: An Active Microchannel Neural Interface for Implantable Electrical Stimulation and Recording ispublished: inpress divisions: UCL divisions: B04 divisions: F42 note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher's terms and conditions. abstract: A mm-sized, implantable neural interface for bidirectional control of the peripheral nerves with microchannel electrodes is presented in this paper. The application-specific integrated circuit (ASIC) developed in a 0.18 μm CMOS technology is designed to achieve highly selective, concurrent control of 300-μm-wide groups of small nerve sections. It has in-situ, high-voltage-compliant (45 V) electrical stimulation and low-voltage (1.8 V) neural recording in each channel. Biphasic stimulus current pulses up to 124 μA with a 2 μA resolution are generated between 7.4 Hz and 20 kHz frequencies to stimulate and block neural activity. Action potentials are measured across a 10 kHz bandwidth with a variable gain response that ranges up to 72 dB. The neural recording front-end implements a low-power and low-noise biopotential amplifier with an input-referred noise (IRN) of 2.74 μVrms across the full measurement bandwidth. Automatic detection and reduction of stimulus artifacts is realised using a pole-shifting mechanism with a 1-ms amplifier recovery time. Versatile control of concurrently-operating channels is achieved in a two-channel, 2.31 mm2 interface ASIC using local control that allows up to seven devices to operate in parallel. Invitro validation of the active interface shows feasibility for closed-loop peripheral nerve control, while ex-vivo analyses of concurrent stimulation and recording demonstrates the measured neural response to electrical stimuli. date: 2025-01-27 date_type: published publisher: Institute of Electrical and Electronics Engineers (IEEE) official_url: https://doi.org/10.1109/tbcas.2025.3533612 oa_status: green full_text_type: other language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2357078 doi: 10.1109/tbcas.2025.3533612 lyricists_name: Lancashire, Henry lyricists_id: HTLAN52 actors_name: Flynn, Bernadette actors_id: BFFLY94 actors_role: owner full_text_status: public publication: IEEE Transactions on Biomedical Circuits and Systems pagerange: 1-13 citation: Habibollahi, Maryam; Jiang, Dai; Lancashire, Henry Thomas; Demosthenous, Andreas; (2025) An Active Microchannel Neural Interface for Implantable Electrical Stimulation and Recording. IEEE Transactions on Biomedical Circuits and Systems pp. 1-13. 10.1109/tbcas.2025.3533612 <https://doi.org/10.1109/tbcas.2025.3533612>. (In press). Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10204210/1/An_Active_Microchannel_Neural_Interface_for_Implantable_Electrical_Stimulation_and_Recording.pdf