A system on chip (SoC) includes a display controller configured to receive data of a current frame and to determine whether the data of the current frame has been updated from data of a previous frame, and a transmitter configured to output a panel self-refresh (PSR) inactive command and the data of the current frame when the display controller determines that the data of the current frame has been updated and to transmit a panel self-refresh (PSR) active command when the display controller determines that the data of the current frame has not been updated.