1024-Electrode Deep Brain Probe Readout Circuit with 1024 Configurable Channels in 55nm CMOS

This paper demonstrates a 1024-electrode, 1024-channel, $20\mu \mathrm{m}\times 30\mu \mathrm{m}$ pixel size, $512\times 2$ deep brain probe readout circuit. A high dynamic range hybrid ADC is designed for the brain probe circuit. This proposed ADC bases on a chopped-type quantized structure. A band pass filter is formed by the integrator and chopper to improve SNR of the circuit. Furthermore, dynamic range of the readout circuit is improved since a non-uniformity circuit is implemented in-pixel. By in-pixel quantization of signals detected by electrodes, each electrode matches specific channel. As a result, even larger array can be output rapidly. Proposed deep brain probe circuit is realized using 55nm 1P6M CMOS process. Power consumption of single channel is 40$\mu$W with noise of 4$\mu$V.