Circuits and methods for detecting and amplifying sensor and sensor array (102, 104) output signals are presented. According to some aspects, a nonlinear feedback loop containing a sensor element provides a nonlinear transformation that compensates for a corresponding nonlinear response of the sensor element thereby providing a linearized final output signal. In other aspects, idle sensors are coupled to a reference on non-idle sensor elements. Other aspects include sensor and amplification circuits which operate without traditional filtering or switching elements, such that a higher throughput is achieved and no settling time is required due to traditional transients, thus allowing for faster scanning of larger sensor arrays. Some embodiments of the present invention are directed to variable gap capacitive sensor arrays and the signal processing electronics.