A 128 x 128 cmos biosensor array for extracellular recording of neural activity

TLDR

Sensor arrays are essential tools for noninvasive recording of activity in biological networks such as dissociated neurons or neural tissue. The authors present a high‑density CMOS chip with 16 000 pixels, a 2 kfps frame rate, 7.8 µm pitch, and mismatch‑canceling calibration circuitry using current‑mode signal representation, addressing circuit, system, and process challenges. Initial biological experiments demonstrate the chip’s full functionality for extracellular neural recording.

Abstract

Sensor arrays are a key tool in the field of neuroscience for noninvasive recording of the activity of biological networks, such as dissociated neurons or neural tissue. A high-density sensor array complementary metal-oxide-semiconductor chip is presented with 16 K pixels, a frame rate of 2 kiloframes per second, and a pitch of 7.8 μm × 7.8 μm for imaging of neural activity. The related circuit and system issues as well as process aspects are discussed. A mismatch-canceling calibration circuitry with current mode signal representation is used. Results from first biological experiments are presented, which prove full functionality of the chip.