Wide input range 1.7μW 1.2kS/s resistive sensor interface circuit with 1 cycle/sample logarithmic sub-ranging

A wide input range 1.7μW, 1.2kS/s resistive sensor interface circuit fabricated in 0.18μm CMOS is presented. This circuit consumes 6.6× lower power and 31.8× less energy than previous state-of-the-art work, considering the worst-case cycle count required for correct conversion. The proposed design uses a logarithmic subrange detector based on comparator metastability to convert an input resistance ranging from 10kΩ to 10MΩ in 1 cycle/sample.