Display device

A display device comprising:

• a display panel in which a plurality of sub-pixels are disposed;
• a data driver circuit configured to apply a plurality of data voltages to the plurality of sub-pixels through a plurality of data lines;
• a driving voltage supply circuit configured to apply a driving voltage to the display panel;
• and
• a power management circuit connected to receive a feedback driving voltage from the display panel, receive the driving voltage output from the driving voltage supply circuit, and configured to output a gamma reference voltage to the data driver circuit,
• a feedback driving voltage line connected between the display panel and the power management circuit;
• and
• a driving voltage line connected between the driving voltage supply circuit and the power management circuit;
• wherein the power management circuit comprises:
• a register configured to store data related to a variation in the driving voltage;
• a first analog-to-digital converter connected between the feedback driving voltage line and the register and converting the feedback driving voltage into a digital form;
• a second analog-to-digital converter connected between the driving voltage line and the register and converting the driving voltage into a digital form;
• and
• a first subtractor circuit configured to calculate a difference value between an output of the first analog-to-digital converter and an output of the second analog-to-digital converter and provide the difference value to the register;
• and
• wherein the gamma reference voltage is variable based on the feedback driving voltage.