A temperature sensor with glucose sensor interface based on configurable incremental sigma delta ADC

Abstract

This paper presents a temperature sensor with glucose sensor interface based on configurable incremental sigma delta (ΣΔ) Analog-Digital-Converter (ADC). A current readout circuit is implemented based on the same ΣΔ modulator of the temperature sensor. New dynamic biasing scheme of inverter-based operational transconductance amplifier (OTA) is proposed to improve the settling time of the biasing voltages. This design was fabricated using 0.13 µm CMOS process. Compared with the traditional circuit, this circuit reduced the chip area by 25%. According to the test results, when the temperature changes from 20°C to 50°C, the temperature sensor inaccuracy is ±0.15 °C and the ADC achieves 9.3 effective number of bits (ENOB) with 3 µW power consumption.