Programmable Transimpedance Amplifier with Integrated Bandgap Reference for Glucose Concentration Measurement

TL;DR

This paper presents a CMOS-based programmable transimpedance amplifier with integrated bandgap reference for glucose sensors, offering wide dynamic range, low noise, and compact size, suitable for electrochemical glucose measurement.

Contribution

It introduces a novel programmable transimpedance amplifier with integrated bandgap reference, optimized for glucose sensing applications in CMOS technology.

Findings

Achieved transimpedance of 17.3-50.5 kohm with low noise

Demonstrated linear response for input currents 4.2-180 uA

Validated glucose measurement from 1 to 10 mM

Abstract

For glucose electrochemical sensors, a comprehensive electronics interface is designed and constructed in 0.18 um, CMOS process technology, and 1.5 V supply voltage. This interface includes a programmable readout amplifier and bandgap reference voltage potentiostat circuit. The programmable transimpedance amplifier (PTIA), the proposed readout circuit, provides a large dynamic range and low noise. The overall transimpedance increase for the PTIA is 17.3-50.5 kohm. For an input current range of 4.2-180 uA, the PTIA response has a linear output voltage range of 0.55-1.44 V. The output rms noise value is calculated to be 5.101 Vrms, and the overall power consumption of the design is 2.33 mW. The THD percentage spans from 7.6 to 10.2 in the current range mentioned above. All bandgap reference voltage potentiostat measurements are made using the reference potential of 0.6 V. The working electrode was a glassy carbon electrode (GCE) loaded with a CuO/Cu0:76CO2:25O4 (copper cobaltite) coating. An electrochemical glucose sensing setup has been used to measure glucose concentrations between 1 and 10 mM, and an emulated circuit has been used to verify the viability of the proposed glucose sensing design. The suggested glucose sensor architecture has a total size of 0.0684 mm2.