Capacitive scan method without display flicker

An electronic device comprising:

• a touch sensing panel including a plurality of transmitting (TX) touch sensors and a plurality of receiving (RX) touch sensors, and
• a touchscreen controller coupled to the touch sensing panel, the touchscreen controller including:
• a TX circuit configured to transmit a first plurality of excitation signals to the plurality of TX touch sensors simultaneously during a first time frame, wherein the first plurality of excitation signals is determined in accordance with a first plurality of codes, and wherein a sum of the first plurality of codes is a sequence of numbers having a same absolute value and signs alternating between adjacent numbers, wherein the first plurality of codes are vectors of length L, L being a positive integer, wherein elements of the vectors are either a positive value “X” or a negative value “−X,” and wherein L divided by a period of the first time frame is larger than a flicker fusion threshold;
• and
• a RX circuit configured to receive a first plurality of output signals from the plurality of RX touch sensors during the first time frame, wherein the touchscreen controller is configured to determine touch strengths in accordance with the first plurality of output signals.