Capacitive sensing with multi-pattern scan

A method comprising:

• concurrently driving, by a processing device, a first set of two or more drive (TX) electrodes of a touch panel of electrodes;
• concurrently driving a second set of two or more TX electrodes of the touch panel;
• concurrently receiving two or more first signals from a first set of two or more sensing (RX) electrodes of the panel of electrodes in response to driving the first set of two or more TX electrodes concurrently;
• concurrently receiving two or more second signals from a second set of two or more RX electrodes of the panel of electrodes in response to driving the second set of two or more TX electrodes concurrently;
• determining, by the processing device, a first capacitance for a first unit cell comprising at least four intersections of the first set of two or more TX electrodes and the first set of two or more RX electrodes, the first capacitance is determined from a generated first digital value representative of the first capacitance for the first unit cell;
• determining a second capacitance for a second unit cell comprising at least four intersections of the second set of two or more TX electrodes and the second set of two or more RX electrodes, the second capacitance is determined from a generated second digital value representative of the second capacitance for the second unit cell;
• generating a first image based on the first capacitance;
• generating a second image based on the second capacitance;
• and
• generating a combined image based on the first image and the second image, and
• determining, based on the first capacitance and the second capacitance, a presence of a ridge or valley of a fingerprint on the touch panel of electrodes,
• wherein the at least four intersections of the second unit cell comprise at least two intersections of the first unit cell,
• wherein a first number of TX electrodes of the first and second sets of two or more TX electrodes is different than a second number of RX electrodes of the first and second sets of two or more RX electrodes, and
• wherein the combined image comprises:
• an odd pixel column comprising the first capacitance, and
• an even pixel column comprising the second capacitance.

A touch detection system comprising:

• a touch panel of electrodes comprising:
• a first set of drive (TX) electrodes disposed along first axis of the touch panel;
• a first set of two or more sensing (RX) electrodes disposed along a second axis of the touch panel, the first set of TX electrodes and the first set of two or more RX electrodes forming a first intersection and a second intersection, wherein a first number of TX electrodes in the first set of TX electrodes is different than a second number of RX electrodes in the first set of two or more RX electrodes;
• and
• a second set of two or more RX electrodes disposed along the second axis of the touch panel, the first set of TX electrodes and the second set of two or more electrodes forming the second intersection and a third intersection;
• a scan control circuit, operatively coupled to the touch panel of electrodes, to concurrently select the first set of two or more electrodes and to concurrently selected the second set of two or more electrodes via a multiplexer;
• an analog front end (AFE) configured to:
• generate a first digital value representative of a first mutual capacitance of a first unit cell, wherein the first unit cell comprises the first intersection and the second intersection;
• and
• generate a second digital value representative of a second mutual capacitance of second a unit cell, wherein the second unit cell comprises the second intersection and the third intersection;
• a channel engine, operatively coupled to the AFE, configured to generate a first capacitance value and a second capacitance value corresponding to the first unit cell and the second unit cell, respectively;
• and
• a memory, operatively coupled to the AFE, configured to store the first capacitance value and the second capacitance value generated by the channel engine,
• a fingerprint controller that determines, based on a combined image, a presence of a ridge or valley of a fingerprint on the touch panel of electrodes,
• wherein the combined image is generated based on a first image, which is generated based on the first capacitance value, and a second image, which is generated based on the second capacitance value, and
• wherein the combined image comprises:
• an odd pixel column comprising the first capacitance value;
• and
• an even pixel column, comprising the second capacitance value.