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Title: 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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Award ID(s):
1707316 1545858
Publication Date:
Journal Name:
IEEE transactions on biomedical circuits and systems
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Sponsoring Org:
National Science Foundation
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