Low power design of analog sensing with sigma delta modulator for MEMS micro-accelerometers applications

The proposed a multi-level force-feedback analog sensing circuits with a continuous-time quadrature band pass sigma-delta (ΣΔ) modulator integration and cicFF topology are presented for positron emission tomography front-end and micro-electro-mechanical systems (MEMS) micro-accelerometers. The proposed circuits are attractive due to that the multi-level force-feedback circuits are proposed to null the sensor and traditionally dependent on zero crossing discriminators, external voltage references, or fixed voltage references with restricted voltage steps that adopts the weighted capacitor technology to save a feed forward summation amplifier, hence reduces power consumption for micro-accelerometers applications.