title: A Wireless FSCV Monitoring IC With Analog Background Subtraction and UWB Telemetry.
abstract: A 30-μW wireless fast-scan cyclic voltammetry monitoring integrated circuit for ultra-wideband (UWB) transmission of dopamine release events in freely-behaving small animals is presented. On-chip integration of analog background subtraction and UWB telemetry yields a 32-fold increase in resolution versus standard Nyquist-rate conversion alone, near a four-fold decrease in the volume of uplink data versus single-bit, third-order, delta-sigma modulation, and more than a 20-fold reduction in transmit power versus narrowband transmission for low data rates. The 1.5- mm(2) chip, which was fabricated in 65-nm CMOS technology, consists of a low-noise potentiostat frontend, a two-step analog-to-digital converter (ADC), and an impulse-radio UWB transmitter (TX). The duty-cycled frontend and ADC/UWB-TX blocks draw 4 μA and 15 μA from 3-V and 1.2-V supplies, respectively. The chip achieves an input-referred current noise of 92 pA(rms) and an input current range of ±430 nA at a conversion rate of 10 kHz. The packaged device operates from a 3-V coin-cell battery, measures 4.7 × 1.9 cm(2), weighs 4.3 g (including the battery and antenna), and can be carried by small animals. The system was validated by wirelessly recording flow-injection of dopamine with concentrations in the range of 250 nM to 1 μM with a carbon-fiber microelectrode (CFM) using 300-V/s FSCV.
authors.forename: Carlos I
authors.initials: CI
authors.lastname: Dorta-Quiñones
authors.forename: Xiao Y
authors.initials: XY
authors.lastname: Wang
authors.forename: Rajeev K
authors.initials: RK
authors.lastname: Dokania
authors.forename: Alycia
authors.initials: A
authors.lastname: Gailey
authors.forename: Manfred
authors.initials: M
authors.lastname: Lindau
authors.forename: Alyssa B
authors.initials: AB
authors.lastname: Apsel
mesh_terms: D000703:Analog-Digital Conversion; D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008839:Microelectrodes; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation; D013686:Telemetry / Q000295:instrumentation*; D059015:Wireless Technology / Q000295:instrumentation*
chemical_list: D004298:Dopamine