Abstract: Some disclosed methods involve controlling a fingerprint sensor system to scan a portion of a user's digit on a surface of an apparatus using a plurality of trial fingerprint sensor system parameters and selecting, from among the trial fingerprint sensor system parameters, one or more personalized fingerprint sensor system parameters for inclusion in a set of personalized fingerprint sensor system parameters. Some disclosed methods involve selecting, based on the one or more personalized fingerprint sensor system parameters, an existing fingerprint sensor system parameter data structure that includes a set of existing fingerprint sensor system parameters, obtaining additional fingerprint sensor system parameters from the set of existing fingerprint sensor system parameters for inclusion in the set of personalized fingerprint sensor system parameters, and storing the set of personalized fingerprint sensor system parameters for future scans of the fingerprint sensor system.

Abstract: Methods, devices and systems for controlling an ultrasonic fingerprint sensor are disclosed. Some examples involve determining that a first bias voltage is not sufficient for one or more affected ultrasonic receiver pixels of the ultrasonic receiver array and determining one or more affected regions of the ultrasonic receiver array in which the one or more affected ultrasonic receiver pixels are located. Some examples involve determining one or more unaffected regions of the ultrasonic receiver array in which the one or more affected ultrasonic receiver pixels are not located. Some examples involve determining a second bias voltage for the one or more affected regions and recalibrating the ultrasonic fingerprint sensor to apply the second bias voltage to the affected regions and to apply the first bias voltage to the one or more unaffected regions when the ultrasonic receiver array receives ultrasound signals.