An implantable mixed-signal CMOS die for battery-powered in vivo blowfly neural recordings

作者：Yue Xicai^*; Huang Jiaqi V; Krapp H G; Drakakis E M

来源：Microelectronics Journal, 2018, 74: 34-42.

DOI：10.1016/j.mejo.2018.01.022

• Implantable neural recording
• Blowfly
• CMOS neural amplifier
• SAR ADC

A mixed-signal die containing two differential input amplifiers, a multiplexer and a 50 KSPS, 10-bit SAR ADC, has been designed and fabricated in a 0.35 mu m CMOS process for in vivo neural recording from freely moving blowflies where power supplied voltage drops quickly due to the space/weight limited insufficient capacity of the battery. The designed neural amplifier has a 66 + dB gain, 0.13 Hz-5.3 KHz bandwidth and 0.39% THD. A 20% power supply voltage drop causes only a 3% change in amplifier gain and 0.9-bit resolution degrading for SAR ADC while the on-chip data modulation reduces the chip size, rendering the designed chip suitable for battery-powered applications. The fabricated die occupies 1.1 mm(2) while consuming 238 mu W, being suitable for implantable neural recordings from insects as small as a blowfly for electrophysiological studies of their sensorimotor control mechanisms. The functionality of the die has been validated by recording the signals from identified interneurons in the blowfly visual system.

• 出版日期2018-4