A Neural Recording IC Design with on-chip CMOS Electrode Array for Brain-machine Interface

This paper presents an integrated circuit design for neural recording chip with integrated CMOS electrode array. The implementation of on-chip electrode array can greatly improve the implantability of neural recording systems. The chip is mainly composed of a neural recording analog front end and an $8\times 8$ microelectrode array designed in CMOS process technology. The analog front end of the neural recording circuit adopts chopper technique, which effectively reduces the low-frequency noise. The whole circuit has been designed in Cadence using the SMIC 180-nm CMOS process. The simulation results show that the signal with a frequency ranging from 0-2kHz and the amplitude ranging from $0-500 \ \mu \mathrm{V}$ can be independently recorded through the electrodes with a control terminal. The electrode array and the recording analog front end IC are partly overlapped using different metal layers, saving the chip area. The chip area of the final circuit with 64 electrodes is only 1400 $\mu \mathrm{m}\times 760 \ \mu \mathrm{m}$.