Interface and synchronization method between touch controller and display driver for operation with touch integrated displays

摘要

Apparatuses and methods of synchronizing a display driver integrated circuit (DDI) and a touch screen controller (TSC) integrated circuit that are coupled to a display integrated touch panel, such as an in-cell panel, and allowing multi-phase transmit (TX) scanning of the in-cell touch panel. One apparatus includes a DDI configured to receive signals on a video interface from a host processor over a video interface and to drive electrodes of a touch panel. The DDI is configured to receive control signals from a TSC over a control interface to drive different transmit (TX) phase sequences of a TX signal in different sensing interval on the electrodes of the touch panel.

主权项

1. An electronic system comprising:
a display driver integrated circuit (DDI), wherein the DDI comprises:
a video interface to receive display signals from a host processor;a control interface to receive control signals from a touch screen controller (TSC);a display interface, wherein the DDI is configured to drive electrodes of a touch panel with the display signals in a display mode and to drive the electrodes of the touch panel with transmit (TX) signals for mutual capacitance sensing in a touch sensing mode according to the control signals received on the control interface from the TSC, wherein the DDI is configured to drive different TX signal sequences of a TX signal in different sensing intervals on the electrodes of the touch panel for multi-phase scanning; andmemory to store a TX pattern matrix of the different TX signal sequences of the TX signal, wherein the control signals are configured to control output of the TX pattern matrix on the electrodes of the touch panel, wherein the TX pattern matrix comprises a plurality of rows corresponding to the electrodes and a plurality of columns corresponding to the different sensing intervals, wherein a plurality of matrix elements of the TX pattern matrix store different values for the different TX signal sequences during the different sensing intervals, wherein a first value indicates an in-phase TX signal is to be applied to the corresponding electrode, a second value indicates an out-of-phase TX signal is to be applied to the corresponding electrode and a third value indicates a high-impedance (Hi-Z) output is to be applied to the corresponding electrode, and wherein the touch panel is an in-cell touch panel in which common electrodes are configured as a TX layer during the touch sensing mode of the in-cell touch panel and as a common voltage reference layer during the display mode of the in-cell touch panel.