A touch display device can include a panel including touch electrodes; a touch/data driver to drive data lines and the touch electrodes of the panel, read out capacitance variations in the touch electrodes and output sensing data; a gate driver to drive gate lines of the panel; a timing controller to control display operations of the touch/data driver and the gate driver; a microcontroller unit (MCU) to control touch driving and sensing operations of the touch/data driver; a first power circuit to drive the timing controller and the gate driver using a main voltage supplied through a first power line; a multiplexer to output one of a universal serial bus (USB) voltage supplied through a second power line and the main voltage supplied through the first power line; a second power circuit configured to drive the touch/data driver, the gate driver and the MCU based on an output voltage from an output of the multiplexer; and a switch connected between the output of the multiplexer and the second power line, the switch being configured to switch the output of the multiplexer to the second power line.