Abstract

We present a high electrode density and high channel count CMOS (complementary metal-oxide-semiconductor) active neural probe containing 1344 neuron sized recording pixels (20 µm × 20 µm) and 12 reference pixels (20 µm × 80 µm), densely packed on a 50 µm thick, 100 µm wide, and 8 mm long shank. The active electrodes or pixels consist of dedicated in-situ circuits for signal source amplification, which are directly located under each electrode. The probe supports the simultaneous recording of all 1356 electrodes with sufficient signal to noise ratio for typical neuroscience applications. For enhanced performance, further noise reduction can be achieved while using half of the electrodes (678). Both of these numbers considerably surpass the state-of-the art active neural probes in both electrode count and number of recording channels. The measured input referred noise in the action potential band is 12.4 µVrms, while using 678 electrodes, with just 3 µW power dissipation per pixel and 45 µW per read-out channel (including data transmission).

Highlights

  • The need for large-scale neural recording across multiple brain areas in behaving animals has driven the recent development of high density neural probes [1]

  • A reduction of local field potential (LFP) noise is possible by software averaging multiple channels, as LFP signals have low spatial resolution

  • By implementing various innovative circuit design techniques we have succeeded in designing a new type of neural amplifier

Read more

Summary

Introduction

The need for large-scale neural recording across multiple brain areas in behaving animals has driven the recent development of high density neural probes [1]. Prior active [2,3,4] and passive [9,13,14,15] neural probes used a dedicated metal line per electrode to send the signal to the base circuitry This one-to-one mapping results in either a limited number of electrodes present on the shank [9] or the recording of a statically selected subset [2,4,15] (Figure 2a). Supply with increased drop and ripple, dense layout prone to capacitive coupling, and a requirement for low complexity circuits, which provide the desired functionality and low noise This architecture and circuit implementations presented maximize the readout capability of a given inserted shank by simultaneously recording all of the available electrodes.

Overview
Noise Folding
Power Limitation
Architecture
Circuit Description
Shank Power Supply
Calibration and Reset
Recording Performance
Channel
Device Fabrication
System
Electrical Performance
In-Vivo Neural Recordings
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call