In this paper, a reconfigurable low-noise fully integrated capacitive sensor frontend with an on-chip tuning scheme is proposed to enhance the flexibility, reliability, and accuracy with a low power consumption. The sensor frontend is composed of a charge sensitive amplifier with a new reset network followed by three band-pass amplifiers to further amplify the output signal and also to achieve a Gaussian pulse shaping. The frontend can process the signals of both polarities and the effect of the sensor dark current on the output is negligible. The readout circuit is simulated using a standard 0.18 μm CMOS process. The post-layout simulation results prove a highly tunable conversion gain and show a maximum value of 25.7 mV/fC and equivalent noise charge (ENC) of about 106 e-rms with a power consumption of 371 μW.