A Low-Noise Ex-Vivo CMOS MEA with 4k Recording Sites, 4k Recording Channels, and 1k Stimulation Sites

Abstract

A Multi-Electrode-Array (MEA) in a 180 nm CMOS technology is presented with 4225 recording sides, 4225 recording channels, and 1024 stimulation sites. The two versions of the chip provide active areas of 2.3 mm x 2.3 mm and 4.1 mm x 4.1 mm with a spacial recording site resolution of 36 μm and 64 μm, respectively. The devices are capable of full imaging at a frame rate of 25 kHz at an input-referred noise of 13.1 μVrms in the action potential (AP) band from 300 Hz to 10 kHz, 10 μVrms in the AP band from 300 Hz to 6 kHz, and 15.1 μVrms in the local field potential (LFP) band from 1 Hz to 300 Hz. To reach these noise levels the signals from the recording sites are routed out of the active array to dedicated low noise amplifiers in the periphery. Crosstalk between the related pixels is significantly reduced by individual actively shielded traces.