This paper presents a low-noise, wireless neural recorder that has a frequency dependent amplification to remove electrode offset and to attenuate motion artifacts. The recorder has 2.5 GΩ and 50 MΩ input impedance at 20 Hz and 1 kHz for recording local field potentials and extracellular spikes, respectively. To reduce the input-referred noise, we propose a low-noise frontend design with multiple novel noise suppression techniques. To reduce the power consumption, we have integrated an exponential component and polynomial component spike processor that automatically adjusts the recording bandwidth based on the signal contents. In bench-top measurement, the proposed neural recorder has 2.2- μ V input-referred noise integrated from 300 Hz to 8 kHz and consumes 98- μ W maximum power. In animal experiments, the output data of the neural signal processor are serialized and connected to a customized WiFi data link with up to 10 Mbps data rate. Through in vivo experiments, we find that the noise generated by the WiFi does not prevent brain recordings with microelectrodes and a clear interpretation of the neural signals; however, the noise can mask the weaker neural signals in nerve recordings with epineural electrodes.
|Original language||English (US)|
|Number of pages||14|
|Journal||IEEE Journal on Emerging and Selected Topics in Circuits and Systems|
|State||Published - Jun 2018|
Bibliographical noteFunding Information:
Manuscript received September 14, 2017; revised December 11, 2017; accepted January 15, 2018. Date of publication March 5, 2018; date of current version June 11, 2018. This work was supported in part by the DARPA under Grant HR0011-17-2-0060, in part by the NIH under Grant R01-MH111413-01, and in part by a startup package provided by the College of Science and Engineering and MnDRIVE Program at the University of Minnesota. This paper was recommended by Guest Editor P.-I. Mak. (Corresponding author: Jian Xu.) J. Xu, A. T. Nguyen, W. Zhao, H. Guo, T. Wu, H. Lim, and Z. Yang are with the Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455 USA (e-mail: firstname.lastname@example.org; email@example.com). H. Wiggins is with Plexon Inc., Dallas, TX 75206 USA. E. W. Keefer is with Nerves Inc., Dallas, TX 75214 USA.
- Brain recording
- frequency-shaping recorder
- nerve recording
- neural spike processor
- wireless neural data acquisition