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Micro-power ΔΣ modulators are suitable for low-bandwidth, high-precision applications, such as smart sensors, biomedical signal processing and battery-powered IoT devices. They achieve high SNR by oversampling and noise shaping, but higher order loops have stability problems. The multistage noise-shaping (MASH) technique solves this problem by realizing a high-order NTF with several low-order stages. However, for the MASH structure to be effective, the loop filter integrators must have high gain to avoid quantization noise leakage. Conventionally, they are realized by high-gain OTAs with gain-boosted cascode [1].However, they draw static bias current, and their biasing and common mode feedback (CMFB) make them unattractive in duty-cycled operation in IoT applications due to the long settling time. The floating-inverter amplifier (FIA) [2] does not require biasing and CMFB, which makes it an attractive …