Low power DDA-based instrumentation amplifier for neural recording applications in 65 nm CMOS
The low power instrumentation amplifier (IA) presented in this paper has been designed to be the front-end of an integrated neural recording system, in which common-mode rejection ratio (CMRR), input referred noise and power consumption are critical requirements. The proposed IA topology exploits a differential-difference amplifier (DDA) whose differential output current drives a fully differential, high-resistance, transimpedance stage, with an embedded common-mode feedback loop to increase the CMRR. This stage is followed by a differential-to-single-ended output amplifier.