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This paper reports the first electronic circuit used to measure MEMS resonator motion in the time domain. The measurement of shuttle position is made using a capacitance-to-voltage converter IC that has been developed by combining correlated double sampling with delta modulation in a fully differential circuit topology. This oversampling circuit may be adjusted to trade bandwidth (sample rate) for resolution, while reference level may be adjusted to set the desired sensitivity to accommodate a large range of capacitive sensor interface applications. For example, test results demonstrate a resolution of 170 aF for a signal bandwidth of 3 kHz, a 68-dB dynamic range, and nonlinearity less than 0.16%.