A 94-dB DR,105-Hz bandwidth interface circuit for inertial navigation applications

This paper presents a fully differential high-resolution analog interface circuit to apply in an inertial navigation system. By integrating an anti-aliasing filter and a second order sigma-delta modulator into a single chip, the interface circuit can achieve high-resolution with low power consumption. The prototype fabricated in a 0.25 µm CMOS process achieves a dynamic range (DR) of 94 dB, a SNDR of 83.4 dB over the bandwidth of 105 Hz, where the total power consumption is 363.2 µW at 1.6 V supply. Based on the simulation results the sigma-delta modulator block achieves a SNDR of 101 dB while consuming a power consumption of 43 µW, which yields a Walden Figure of Merit (FoM) of 1.7 pJ/conv-step and a Schreier FoM of 157 dB.