Multi Channel Chopper Modulated Neural Recording System.

摘要

Presented herein is a fully integrated low-noise CMOS multi-channel amplifier for neural recording applications The circuit employs the chopper modulation technique to reduce the effect of flicker noise and DC offset, A reduced area design implementation is achieved by trading off the increased noise margin performance of the chopper modulator for minimal amplifier area and analog multiplexing of the recording sites, A fully differential topology is used for the signal path to improve noise immunity The analog amplifier exhibits 56 dB of gain with a 115 kHz bandwidth and a common mode rejection ratio (CMRR) of 80 dB. Simulation results show a total input referred noise less than 16 nV/ square root of Hz, The system power consumption is approximately 750 microWatts The fully integrated system was designed in ABN 1,6-um single poly n-well CMOS process.