Organic light-emitting display device and method of driving the same

An organic light-emitting display device comprising:

• a display unit comprising a plurality of pixel units, each of the pixel units comprising an organic light-emitting diode (OLED);
• a timing controller is configured to calculate a BBPR and set a driving mode based on the BBPR, wherein the BBPR is a ratio of a number of pixel units in a black state to a total number of pixel units in the display unit;
• and
• a power supply unit is configured to provide a driving voltage corresponding to the set driving mode to the display unit,
• wherein
• the timing controller is configured to set a first driving mode when the BBPR is lower than 90% and to set a second driving mode when the BBPR is 90% or higher, and
• the power supply unit is configured to provide a first driving voltage to a first electrode of the OLED of each of the pixel units when the first driving mode is set and is configured to provide a second driving voltage to the first electrode of the OLED of each of the pixel units when the second driving mode is set, wherein the second driving voltage is higher than the first driving voltage.

A method of driving an organic light-emitting display device, comprising:

• calculating a BBPR, which is a ratio of a number of pixel units in a black state to a total number of pixel units;
• generating a control signal based on the BBPR;
• and
• providing a driving voltage corresponding to the control signal to the pixel units,
• wherein the providing the driving voltage corresponding to the control signal, comprises providing a first driving voltage to the pixel units when the BBPR is less than a reference value and providing a second driving voltage to the pixel units when the BBPR is greater than or equal to the reference value, wherein the second driving voltage is higher than the first driving voltage,
• wherein a difference between the first and second driving voltages is greater than a difference between a black grayscale voltage and a white grayscale voltage.