Compact low noise interfaces for multichannel MEMS thermal sensors

In this work a novel architecture for the design of compact instrumentation amplifier is described. The low offset and low noise characteristics of the proposed amplifier make it particularly suitable for interfacing thermopile-based MEMS sensors. The circuit consists in a fully differential 2nd order low pass Gm-C filter, properly modified to provide gain and incorporate chopper modulation. The validity of the approach is proven by means of simulations performed on a prototype designed with a commercial CMOS process.