Sub-μW front-end low noise amplifier for neural recording applications

Multi-channel neural recording systems are more and more required for neuroscience research and to cope with neurological disorders. Such systems are based on brainimplantable integrated devices with stringent requirements on supply voltage, power consumption and area footprint. A very low power, low noise fully differential front-end amplifier for neural signals processing is presented in this paper. The proposed amplifier architecture exploits two fully differential OTAs with Arbel topology operating in sub-threshold, and allows AC coupling with a high offset electrode while guaranteeing a very low high-pass cut-off frequency without increasing the equivalent input noise. The neural recording front-end has been designed referring to a 0.13-μm CMOS process. The proposed amplifier operates with a supply voltage as low as 0.3V with a mid-band gain of 40dB and a -3dB bandwidth from 0.1 Hz to 10 kHz. Input referred noise and total power consumption are 11 μVrms and 277nW respectively.