Implantable Neural-Recording Modules for Monitoring Electrical Neural Activity in the Central and Peripheral Nervous Systems

Low-power high-fidelity implantable neural-recording modules are presented to monitor electrical neural signals in the central and peripheral nervous systems. For clear measurement of neural spikes, the implemented modules employ double high-pass filters that effectively suppress low-frequency artifacts. Here, we present two different implantable recording modules: one produces analog output, and the other does digital output. The analog-output and digital-output modules are implemented to have 12 channels and 32 channels, respectively. Each implantable module is connected to an external module through a flexible printed-circuit cable. The 32-channel digital-output module has a size of 26 mm × 22 mm while consuming 97 μW of power. For the 12-channel analog-output module, the size is 25 mm × 17 mm, and the power of 57 μW is consumed. The implantable modules are designed to have a low-pass cutoff frequency of 10 kHz. The high-pass cutoff frequency can be controlled from sub-1 Hz to 500 Hz. The implemented implantable modules are successfully applied to in vivo experiments for neural recording in the central and peripheral nervous systems of a rat model.