A display device comprising: a display unit including pixels coupled to scan lines and data lines; a data driver which supplies a data signal to pixels through the data lines; a scan driver which generates a scan signal using a first scan voltage and a second scan voltage, and supplies the scan signal to the pixels through the scan lines; a processor which generates first scan voltage information by setting a first scan voltage level (LVSS1), based on an ambient temperature of the display device;the processor sets the first scan voltage level (LVSS1) to be a first voltage level when the ambient temperature is higher than or equal to a reference temperature, and sets the first scan voltage level (LVSS1) to be a second voltage level when the ambient temperature is lower than the reference temperature, wherein the first voltage level is lower than the second voltage level; a timing controller which generates a power control signal using the first scan voltage information; and a power supply which generates the first scan voltage using the power control signal, and generates the second scan voltage characterized in that the timing controller generates the power control signal using delta voltage information; and the power supply generates delta voltage (ΔV) using the power control signal, and generates the second scan voltage by dropping the delta voltage (ΔV) from the first scan voltage; wherein the power supply includes: a digital-analog converter which generates the first scan voltage, based on the first scan voltage information, and generates the delta voltage (ΔV), based on the delta voltage information; a scan voltage generator which generates the second scan voltage by dropping the delta voltage (ΔV) from the first scan voltage, and supplies the first scan voltage and the second scan voltage to the scan driver; and a scan voltage comparator to which the first scan voltage and the second scan voltage supplied to the scan driver are fed back, which compares the fed-back first and second scan voltages (VSS1, VSS2) with reference voltage (VSS1_REF, VSS2_REF), respectively, and which supplies a comparison result to the scan voltage generator. a display unit including pixels coupled to scan lines and data lines; a data driver which supplies a data signal to pixels through the data lines; a scan driver which generates a scan signal using a first scan voltage and a second scan voltage, and supplies the scan signal to the pixels through the scan lines; a processor which generates first scan voltage information by setting a first scan voltage level (LVSS1), based on an ambient temperature of the display device;the processor sets the first scan voltage level (LVSS1) to be a first voltage level when the ambient temperature is higher than or equal to a reference temperature, and sets the first scan voltage level (LVSS1) to be a second voltage level when the ambient temperature is lower than the reference temperature, wherein the first voltage level is lower than the second voltage level; a timing controller which generates a power control signal using the first scan voltage information; and a power supply which generates the first scan voltage using the power control signal, and generates the second scan voltage characterized in that the timing controller generates the power control signal using delta voltage information; and the power supply generates delta voltage (ΔV) using the power control signal, and generates the second scan voltage by dropping the delta voltage (ΔV) from the first scan voltage; wherein the power supply includes: a digital-analog converter which generates the first scan voltage, based on the first scan voltage information, and generates the delta voltage (ΔV), based on the delta voltage information; a scan voltage generator which generates the second scan voltage by dropping the delta voltage (ΔV) from the first scan voltage, and supplies the first scan voltage and the second scan voltage to the scan driver; and a scan voltage comparator to which the first scan voltage and the second scan voltage supplied to the scan driver are fed back, which compares the fed-back first and second scan voltages (VSS1, VSS2) with reference voltage (VSS1_REF, VSS2_REF), respectively, and which supplies a comparison result to the scan voltage generator. a digital-analog converter which generates the first scan voltage, based on the first scan voltage information, and generates the delta voltage (ΔV), based on the delta voltage information; a scan voltage generator which generates the second scan voltage by dropping the delta voltage (ΔV) from the first scan voltage, and supplies the first scan voltage and the second scan voltage to the scan driver; and a scan voltage comparator to which the first scan voltage and the second scan voltage supplied to the scan driver are fed back, which compares the fed-back first and second scan voltages (VSS1, VSS2) with reference voltage (VSS1_REF, VSS2_REF), respectively, and which supplies a comparison result to the scan voltage generator.