US 12,008,200 B1
Capacitive scan method without display flicker
Kien Beng Tan, Singapore (SG)
Assigned to STMicroelectronics International N.V., Geneva (CH)
Filed by STMicroelectronics International N.V., Geneva (CH)
Filed on Feb. 14, 2023, as Appl. No. 18/169,000.
Int. Cl. G06F 3/041 (2006.01); G06F 3/044 (2006.01)
CPC G06F 3/04184 (2019.05) [G06F 3/0446 (2019.05)] 21 Claims
OG exemplary drawing
 
1. A method for operating a touch sensing panel, the method comprising:
determining, by a touchscreen controller, a first plurality of excitation signals in accordance with a first plurality of codes, 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 in the sequence of 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”;
transmitting, by the touchscreen controller, each of the first plurality of excitation signals to a respective transmitting (TX) touch sensor of the touch sensing panel simultaneously during a first time frame, wherein L divided by a period of the first time frame is larger than a flicker fusion threshold; and
determining, by the touchscreen controller, touch strengths in accordance with a first plurality of output signals received by a plurality of receiving (RX) touch sensors of the touch sensing panel during the first time frame.