Pixel circuit, display device using the same, and display device driving method

A display device comprising:

• a scan driver which generates a scan signal and supplies the scan signal to a scan line;
• a data driver which generates a data signal and supplies the data signal to a data line;
• a display panel comprising a pixel circuit connected to the scan line and the data line;
• and
• a controller which controls the scan driver and the data driver, wherein the pixel circuit comprises:
• an organic light emitting diode;
• a threshold circuit which generates an output signal based on an input signal, wherein the threshold circuit has a hysteresis characteristic with respect to an input signal;
• a first transistor comprising a first electrode connected to the data line, a second electrode connected to an input terminal of the threshold circuit, and a gate electrode connected to the scan line,
• a second transistor comprising a first electrode connected to a driving voltage, a second electrode connected to an anode of the organic light emitting diode, and a gate electrode connected to an output terminal of the threshold circuit, wherein the second transistor controls a current amount which flows to the organic light emitting diode from the driving voltage based on the output signal of the threshold circuit and
• a storage capacitor comprising a first end electrically and directly connected to the input terminal of the threshold circuit, and a second end connected to the first electrode of the second transistor.

A method of driving a display device, the method comprising:

• outputting a low-level voltage from a threshold circuit of a pixel circuit of the display device when a voltage of an input signal to the threshold circuit is less than a second voltage;
• and
• outputting a high-level voltage from the threshold circuit when a voltage of the input signal to the threshold circuit becomes greater than the second voltage,
• wherein the pixel circuit comprises:
• an organic light emitting diode;
• the threshold circuit which generates an output signal based on the input signal, wherein the threshold circuit has a hysteresis characteristic with respect to the input signal;
• a first transistor comprising a first electrode connected to a data line of the display device, a second electrode connected to an input terminal of the threshold circuit, and a gate electrode connected to a scan line of the display device;
• a second transistor comprising a first electrode connected to a driving voltage, a second electrode connected to an anode of the organic light emitting diode, and a gate electrode connected to an output terminal of the threshold circuit, wherein the second transistor controls a current amount which flows to the organic light emitting diode from the driving voltage based on the output signal of the threshold circuit, and
• a storage capacitor comprising a first end electrically and directly connected to the input terminal of the threshold circuit, and a second end connected to the first electrode of the second transistor.