A Novel Analog Autocalibrating Phase-Voltage Converter for Signal Phase-Shifting Detection

In this study, we present a novel analog read-out circuit, operating a phase-voltage conversion, suitable for the detection of signal phase shifting for micro- and nano-sensor system applications. Its main characteristics are the following: good linearity in the considered phase-shift range, capability of phase sign detection, independence from input signal amplitudes, setting and zeroing of the offset, autocalibration, high sensitivity and resolution, and high accuracy and precision. For these reasons and, in particular, thanks to its simple internal topology, the developed circuit can be considered as a suitable analog interface for portable measurement systems. Experimental results, achieved through a laboratory breadboard and using sample signals, have confirmed, with respect to the other solutions reported in literature, better linearity, higher sensitivity (equal to about 37 mV/degree in the ±90^° phase-shift range) and resolution (lower than 0.1^° in the same phase-shift range) for both positive and negative phase variations. When a more reduced phase-shift range must be detected (i.e., for optical sensor applications), it is possible to set the circuit parameters to further increase sensitivity and resolution.