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This paper presents a low noise, high resolution and large dynamic range capacitive readout circuit for Micro-Electromechanical System accelerometer applying to seismic exploration. In comparison to conventional correlated double sampling structure, the proposed correlated double sampling structure is easier to realize, and the correlated double sampling capacitor in conventional structure is removed, also the number of switches is reduced to decrease switch thermal noise. The low frequency 1/f noise and offset voltage of op-amps are suppressed so as to improve resolution and increase dynamic range. The readout circuit chip has been fabricated using X-FAB 0.18-µm complementary metal-oxide-semiconductor technology, which measures 3.5mm2. Test results show that the capacitive resolution of the readout circuit is 2.5aF and the dynamic range reaches 127dB with a sampling frequency of 128 kHz. The readout circuit achieves a noise floor of -115 dBV / Hz at 100Hz with a sensitivity of 0.71mV/fF. [ABSTRACT FROM AUTHOR]

This paper presents a low noise, high resolution and large dynamic range capacitive readout circuit for Micro-Electromechanical System accelerometer applying to seismic exploration. In comparison to conventional correlated double sampling structure, the proposed correlated double sampling structure is easier to realize, and the correlated double sampling capacitor in conventional structure is removed, also the number of switches is reduced to decrease switch thermal noise. The low frequency 1/f noise and offset voltage of op-amps are suppressed so as to improve resolution and increase dynamic range. The readout circuit chip has been fabricated using X-FAB 0.18-μm complementary metal-oxide-semiconductor technology, which measures 3.5mm2. Test results show that the capacitive resolution of the readout circuit is 2.5aF and the dynamic range reaches 127dB with a sampling frequency of 128 kHz. The readout circuit achieves a noise floor of -115 dBV / √Hz at 100Hz with a sensitivity of 0.71mV/fF. [ABSTRACT FROM AUTHOR]