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A triple-sampling <inline-formula> <tex-math notation="LaTeX">$\Delta \Sigma $ </tex-math></inline-formula> ADC can replace the programmable gain amplifier commonly used in the readout circuit for a digital capacitive MEMS microphone. The input voltage can then be multiplied by subtracting a further half-period delayed differential input and using the feedback capacitor of the DAC as a sampling capacitor. This triple-sampling technique results in a readout circuit with noise performance comparable to recent designs, but with a reduced power requirement and increased sensitivity. A MEMS microphone incorporating this readout circuit, fabricated in a <inline-formula> <tex-math notation="LaTeX">$0.18~\mu \text{m}$ </tex-math></inline-formula> CMOS process, had an area of 0.98mm², achieved an A-weighted SNR of 62.1 dBA at 94 dBSPL with 520 <inline-formula> <tex-math notation="LaTeX">$\mu \text{A}$ </tex-math></inline-formula> current consumption, to which triple-sampling was shown to contribute 4.5 dBA.