System and method for detecting and characterizing touch inputs at a human-computer interface

A system comprising:

• a substrate:
• an array of drive electrode and sense electrode pairs arranged on the substrate;
• a touch sensor surface arranged over the substrate;
• and
• a controller configured to:
• during a first scan cycle:
• read a first sense signal from a first drive electrode and sense electrode pair, in the array of drive electrode and sense electrode pairs;
• detect a first alternating component of the first sense signal;
• detect a first direct component of the first sense signal;
• and
• in response to a first magnitude of the first direct component of the first sense signal falling below a threshold magnitude, detect a first input on the touch sensor surface at a first location proximal the first drive electrode and sense electrode pair based on the first alternating-current component of the first sense signal;
• and
• during a second scan cycle:
• read a second sense signal from a second drive electrode and sense electrode pair, in the array of drive electrode and sense electrode pairs;
• detect a second direct component of the second sense signal;
• and
• in response to the second magnitude of the second direct component of the second sense signal exceeding the threshold magnitude, detect a second input on the touch sensor surface at a second location proximal the second drive electrode and sense electrode pair based on the second direct-current component of the second sense signal.

A method comprising:

• during a first scan cycle:
• reading a first set of sense signals from a set of drive electrode and sense electrode pairs;
• and
• detecting a first input at a first location on a touch sensor surface during the first scan cycle based on a first direct component of a first sense signal, in the first set of sense signals, indicating a first change in electrical values between a first drive electrode and sense electrode pair, in the set of drive electrode and sense electrode pairs, located proximal the first location;
• during a second scan cycle succeeding the first scan cycle:
• reading a second set of sense signals from the set of drive electrode and sense electrode pairs;
• and
• tracking the first input from the first location to a second location on the touch sensor surface during the second scan cycle based on a second direct component of a second sense signal, in the second set of sense signals, indicating a second change in electrical values between a second drive electrode and sense electrode pair, in the set of drive electrode and sense electrode pairs, located proximal the second location;
• and
• during a third scan cycle succeeding the second scan cycle:
• reading a third set of sense signals from the set of drive electrode and sense electrode pairs;
• detecting a third direct component of a third sense signal read from a third drive electrode and sense electrode pair, in the set of drive electrode and sense electrode pairs, located proximal a third location on the touch sensor surface;
• detecting a third alternating component of the third sense signal;
• and
• in response to a third magnitude of the third direct component falling below a threshold magnitude, tracking the first input from the second location to the third location on the touch sensor surface during the third scan cycle based on the third alternating component of the third sense signal.