A 16-channel chip for wireless in vivo recording of chemical and electrical neural activity is described. The 7.83-mm<sup>2</sup>
IC is fabricated using a 0.5-μm CMOS process and incorporates a 71-μW, 3rd-order, reconfigurable, ΔΣ modulator per
channel, achieving an input-referred noise of 4.69 μV<sub>rms</sub> in 4-kHz BW and 94.1 pA<sub>rms</sub> in 5-kHz BW for electrical and
fast-scan voltammetric chemical neurosensing, respectively. The chip has been externally interfaced with carbon-fiber
microelectrodes implanted acutely in the caudate-putamen of an anesthetized rat, and, for the first time, extracellular
levels of dopamine elicited by electrical stimulation of the medial forebrain bundle have been successfully recorded
wirelessly across multiple channels using 300-V/s fast-scan cyclic voltammetry.