A display driving device capable of operating a source driver integrated circuit (IC) in a low power mode during a touch sensing period includes a source driver IC configured to operate in a first low power mode in which an analog data processing unit is deactivated or operate in a second low power mode in which both of the analog data processing unit and a digital data processing unit are deactivated, during a touch sensing period of a first frame; and a readout IC configured to supply touch sensor driving signals to touch sensors during the touch sensing period and receive touch sensing data from the touch sensors according to the touch sensor driving signals.