公开(公告)号：US20200285384A1

公开(公告)日：2020-09-10

申请号：US16788417

申请日：2020-02-12

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Kusuma Adi NINGRAT ,  Ade PUTRA

IPC: G06F3/041 ,  G06F3/044

Abstract: A touch screen controller includes driving circuitry coupled to a conductive line through a resistance and drives that conductive line with a driving signal passed through the resistance at a drive frequency. Sensing circuitry is coupled to that conductive line and senses a voltage at that conductive line, the voltage being a function of a capacitance seen by that conductive line. Analog to digital conversion circuitry is coupled to the sensing circuitry and samples the sensed voltage at a sampling frequency to produce samples. Processing circuitry is coupled to the analog to digital conversion circuitry and directly calculates a tangent of a phase shift of the voltage due to the resistance and the capacitance from the samples, and determines a self touch value for that conductive line as a function of the tangent of the phase shift of the voltage.

公开(公告)号：US20190265837A1

公开(公告)日：2019-08-29

申请号：US16406205

申请日：2019-05-08

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Kusuma Adi NINGRAT ,  Ade PUTRA

IPC: G06F3/041 ,  G06F3/044

Abstract: A touch screen controller includes drive circuitry driving force lines with a force signal in a touch data sensing mode and not driving the force lines in a noise sensing mode, sense circuitry sensing touch data at the sense lines in the touch data sensing mode and sensing noise data at the sense lines during the noise sensing mode. Processing circuitry: a) samples the noise data, b) performs trigonometric manipulations of the noise data to produce imaginary noise data and real noise data, and c) determines a noise magnitude value of the noise data as a function of the imaginary noise data and the real noise data. In the noise sensing mode, (a)-(c) are performed for each of a plurality of possible sampling frequencies to be used in the touch data sensing mode in order to determine which sampling frequency is to be used in the touch data sensing mode.