A High-Resolution Low-Power Oversampling ADC with Extended-Range for Bio-Sensor Arrays

Abstract

A calibration-free, high-resolution ADC designed for bioluminescence sensing employs an extended-counting architecture in which the residual error from a second-order incremental SigmaDelta modulator is encoded using a successive approximation ADC. The ADC has been integrated in 0.18-mum CMOS technology and achieves a dynamic range of 90.1 dB and a peak SNDR of 86.3 dB at a conversion rate of 1MSample/sec with 38 mW power consumption.