If the second switch 135 is turned on, the discharge check terminal 136 may recognize that the voltage of the capacitor 134 has not been completely discharged, and output a discharge-uncompleted signal. In alternate embodiments, the discharge check terminal may only output a discharge-completed signal when the voltage of the capacitor has been completely discharged, and no discharge-uncompleted signal is output.

In addition, if the second switch 135 is turned off, the discharge check terminal 136 may recognize that the voltage of the capacitor 134 has been completely discharged, and output a discharge-completed signal.

If the discharge-completed signal is output through the discharge check terminal 136, the processor 190 may determine that the cooling time of the display panel 150 is satisfied.

If the cooling time is satisfied, the processor 190 may perform an afterimage compensation algorithm. To this end, the processor 190 may include an afterimage compensation circuit.

The afterimage compensation circuit may be a circuit for compensating for the deterioration of the pixels of the display panel 150.

The afterimage compensation circuit may include a current sensor for measuring a current flowing through the OLED constituting the pixel.

The afterimage compensation circuit may detect the deterioration degree of the pixel by using a difference between an existing current value and a changed current value with respect to the same voltage.