Organic light emitting display apparatus and driving method thereof

One embodiment of the invention the first and second via the first and second power lines to the timing controller, a display, said display unit to display one frame for each one cycle of the vertical synchronization signal and outputting a vertical synchronization signal the sensor controller which outputs a sensor control signal synchronized to the power supply, the vertical sync signal and outputting the power to each sensor unit to synchronize to the sensor control signal and measuring the amount of current flowing in the first power supply line, and the measured amount of electric current comparing the reference current, and is the level of the voltage of the first power source wherein the basis of the comparison period of the sensor control signal, and a power control unit for controlling parts of the power supply to be adjusted by synchronizing to the sensor control signal of the signal generated by dividing the vertical synchronization signal, the OLED display.