Driving method of display device and display device

A display device, comprising:

• an organic light emitting device, wherein a cathode of the organic light emitting device is connected to a first voltage;
• a first transistor, wherein a drain of the first transistor is connected to an anode of the organic light emitting device;
• and
• a second transistor, wherein a source of the second transistor is connected to a second voltage, a drain of the second transistor is connected to a source of the first transistor, and a capacitor is connected between the gate and the source of the second transistor, wherein
• a frame image signal is generated and outputted by a timing controller to the gate of the second transistor, the frame image signal is stored in the capacitor, the frame image signal comprises an active data region and a blank region based on a time sequence, and after the first transistor is turned on, the frame image signal is input to the organic light emitting device;
• and
• in response to reaching the blank region of the frame image signal as determined by the timing controller, a first voltage at the cathode of the organic light emitting device is changed to compensate an operating current of the display device, thereby maintaining a brightness of a current frame image signal of the display device to be the same as a brightness of a previous frame image signal.