A Low-Power Neuromorphic CMOS Delta-Sigma Modulator Featuring Tunable Background Attenuation and Potentiostatic Asynchronous Readout for Smart Amperometric Electrochemical Sensors
- Resource Type
- Conference
- Authors
- Cuenca-Michans, Javier; Aymerich, Joan; Teres, Lluis; Jimenez-Jorquera, Cecilia; Serra-Graells, Francisco; Margarit-Taule, Josep Maria
- Source
- 2023 IEEE International Symposium on Circuits and Systems (ISCAS) Circuits and Systems (ISCAS), 2023 IEEE International Symposium on. :1-5 May, 2023
- Subject
- Components, Circuits, Devices and Systems
Power, Energy and Industry Applications
Signal Processing and Analysis
Chemical sensors
Quantization (signal)
Neuromorphics
Microprocessors
Computer architecture
Sensor phenomena and characterization
Delta-sigma modulation
Amperometric
delta-sigma modulation
background current
asynchronous
CMOS
electrochemical sensors
potentiostat
neuromorphic
- Language
- ISSN
- 2158-1525
This paper presents a neuromorphic CMOS Delta-Sigma modulator for the robust and energy-efficient readout of amperometric electrochemical sensors. The circuit makes use of an adaptive integrate-and-fire scheme to deliver asynchronous A/D conversion and attenuation of background currents with minimal power requirements. The modulator reuses the dynamic characteristics of the electrode-electrolyte interface for quantization noise shaping, and it offers potentiostatic control of the voltage difference between working and reference electrodes of a three-electrode electrochemical cell. Electrical simulation results are reported at transistor level for a smart electrochemical sensor currently being integrated in a 1.2-V 65-nm 9-metal CMOS technology. The frontend exhibits a tunable off-band rejection of 20 dB with a peak SNR of 61dB and $70-\mu\mathrm{W}$ power consumption.