Driver IC for a display panel with touch device with display state timing in accordance with differing driving periods

摘要

One display frame period is divided into one or a plurality of display driving periods and non-display driving periods, and immediately before transition from the non-display driving period to the display driving period, a dummy driving period is inserted. During the dummy driving period, using dummy data changed from display data at the time of driving stop of a signal electrode during the non-display driving period, driving of the signal electrode starts. Thereafter, a display line is selected, and, using the display data corresponding to each display line selected, the signal electrode is driven.

主权项

1. A driver IC that performs a display by driving a plurality of signal electrodes for each display line of a display panel comprising:
a driving circuit that drives the signal electrodes; and a driving control circuit that controls the driving circuit by dividing one display frame period into a plurality of display driving periods, in which non-display driving periods each follow the display driving period, and dummy driving periods each of which follows the non-display driving period and is prefixed to a next display driving period, wherein the plurality of display driving periods, at least one non-display driving period, and at least one dummy driving period is included between a back porch and a front porch in one display frame period, wherein each said display driving period is one period during which the driving control circuit serially selects a plurality of display lines, wherein the driving control circuit selects the display line and causes the driving circuit to drive the plurality of signal electrodes using corresponding display data for each display line selected, during the display driving period, wherein the driving control circuit does not select the display line and causes the driving circuit to stop a driving of the signal electrodes, during the non-display driving period, wherein the driving control circuit causes the driving circuit to start the driving of the signal electrodes using dummy data changed from the display data at a time of a driving stop of the non-display driving period, during the dummy driving period, wherein the driving control circuit includes, a display RAM that stores the display data, an address generation circuit that generates a read address of the display RAM, and an address control circuit that controls generation of the read address performed by the address generation circuit, wherein the address control circuit includes, a line counter that counts up a line count clock by a display frame unit for each display line cycle designated; a dummy line counter that counts down a dummy line count clock from an initial value for each dummy line cycle designated; and a state control circuit that controls states of the display driving period, the non-display driving period, and the dummy driving period according to a count value of the line counter, wherein the address generation circuit includes a display read address counter that counts up the line count clock, wherein the state control circuit, causes the read address to be generated by counting up the display read address counter during the display driving period, stops a count operation of the display read address counter in a case that transition from the display driving period to the non-display driving period is performed, causes a count operation of the dummy line counter to be performed during a stop of the count operation of the display read address counter, and causes a read address of dummy data to be performed by subtracting the count value from a count value of the display read address counter which is stopped, and wherein the address control circuit performs, a control that updates the read address during the display driving period in synchronization with a display line cycle which is a switching cycle of the display line, and a control that retroactively reads a read address updated during an end of the display driving period and another read address retroactively applied on a basis of the read address, and updates the read addresses as a read address in the dummy driving period.