A 190µW–915MHz active neural transponder with 4-channel time multiplexed AFE

This paper reports a highly integrated neural tag for biosignal streaming data recording. The analog front-end uses a time multiplexed architecture with tunable bandwidth amplifiers, a shared output stage and 8-bit SAR ADC, and achieves an NEF of 2.7 with input referred noise of 18nV/√Hz. Streaming digitized signal recordings are packetized and transmitted via a low power 915MHz backscattering modulator. The chip was fabricated in 130nm CMOS process, measures 1.64mm², and dissipates 190µW when fully operational.