A High-Resolution Opto-Electrophysiology System With a Miniature Integrated Headstage

• Published in: IEEE transactions on biomedical circuits and systems 2018-10, Vol.12 (5), p.1065-1075
• Main Authors: Mendrela, Adam E., Kim, Kanghwan, English, Daniel, McKenzie, Sam, Seymour, John P., Buzsaki, Gyorgy, Yoon, Euisik
• Format: Article
• Language: English
• Subjects: Acidity; ASIC; Biomedical optical imaging; Circuit boards; Circuit design; closed-loop; Computer applications; Digitization; Digitizing; Electrodes; Electrophysiology; Form factors; headstage; High resolution; Implants; In vivo; In vivo electrophysiology; Integrated circuits; LED driver; Light emitting diodes; micro-LED; neural probe; Optical recording; optogenetics; Probes; Radiant flux; Recording; Sodium channels; Stimulation
• ISSN: 1932-4545; 1940-9990; 1940-9990
• DOI: 10.1109/TBCAS.2018.2852267

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 printed circuit boards were designed to link the headstage with a PC. The prototype system demonstrates precise current generation, sufficient optical radiant flux generation (Φ e > 0.16 μW), and fast turn-ON of μLEDs ( t rise