Gate driver for a fingerprint sensor

A sensor, comprising:

• an array of sensing pixels configured to sense a touch for a sensing region of the sensor;
• a gate driver configured to drive a portion of the array of sensing pixels in performing a scan by the sensor, the gate driver including:
• a first flip-flop including a first data input and a first data output, wherein the first data output is coupled to a first group of sensing pixels of the array;
• a second flip-flop including a second data input and a second data output, wherein the second data output is coupled to a second group of sensing pixels of the array;
• and
• a first insertion circuit configured to receive a first start signal and to cause, based on the first start signal, the second flip-flop to drive the second group of sensing pixels without the first flip-flop driving the first group of sensing pixels for a scan of the array;
• and
• a controller configured to control the gate driver to drive the portion of the array in performing the scan.

A method of operating a gate driver for an array of sensing pixels, the method comprising:

• determining a portion of the array of sensing pixels corresponding to one or more touches in a sensing region of a sensor;
• driving the sensing pixels of the array in the portion for a scan by the sensor;
• and
• preventing sensing pixels of the array outside the portion from being driven.