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We present a neural interface system-on-chip (NISoC) with 1,024 channels of simultaneous electrical recording and stimulation for high-resolution high-throughput electrophysiology. The 2mm 2mm NISoC in 65nm CMOS integrates a 32 32 array of electrodes vertically coupled to analog front-ends supporting both voltage and current clamping through a programmable interface, ranging over 100dB in voltage and 120dB in current, with 0.82mW power per channel at 5.96mVrms input-referred voltage noise from DC to 12.5kHz signal bandwidth. This includes onchip acquisition with a back-end array of 32 dynamic incremental SAR ADCs for 25Msps 11-ENOB acquisition at 2fJ/level FOM.
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A High-Resolution Opto-Electrophysiology System with a Miniature Integrated Headstage
This work presents a fully integrated neural interface system in a small form factor (1.9 g), consisting of a μLED silicon optoelectrode (12 μLEDs and 32 recording sites in a 4-shank configuration), an Intan 32-channel recording chip, and a custom optical stimulation chip for controlling 12 μLEDs. High-resolution optical stimulation with approximately 68.5 nW radiant flux resolution is achieved by a custom LED driver ASIC, which enables individual control of up to 48 channels with a current precision of 1 μA, a maximum current of 1.024 mA, and an update rate of > 10 kHz. Recording is performed by an off-the-shelf 32- channel digitizing front-end ASIC from Intan®. Two compact custom interface PCBs were designed to link the headstage with a PC. The prototype system demonstrates precise current generation, sufficient optical radiant flux generation (𝚽𝒆 > 𝟎. 𝟏𝟔 𝛍𝐖), and fast turn-on of μLEDs (𝒕𝒓𝒊𝒔𝒆 < 𝟏𝟎 𝛍𝐬). Single animal in vivo experiments validated the headstage’s capability to precisely modulate single neuronal activity and independently modulate activities of separate neuronal populations near neighboring optoelectrode shanks.
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- PAR ID:
- 10083176
- Date Published:
- Journal Name:
- IEEE transactions on biomedical circuits and systems
- Volume:
- 12
- Issue:
- 5
- ISSN:
- 1932-4545
- Page Range / eLocation ID:
- 1065-1075
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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