Pixel circuit, organic light emitting display, and driving method thereof

An organic light emitting display comprising:

• a scan driver configured to supply scan signals to scan lines and to supply light emission control signals to light emission control lines;
• a data driver configured to supply data signals to data lines;
• and
• a plurality of pixel circuits each located at crossing regions of the scan lines, the light emission control lines, and the data lines,
• wherein each of the pixel circuits comprises:
• an organic light emitting diode;
• a second transistor comprising a gate terminal, a first terminal, and a second terminal coupled to a first scan line of the scan lines, a data line of the data lines, and a first node, respectively;
• a fourth transistor comprising a gate terminal, a first terminal, and a second terminal coupled to a third scan line of the scan lines, the first node, and a second node, respectively;
• a third transistor comprising a gate terminal, a first terminal, and a second terminal coupled to a second scan line of the scan lines, a reference power source, and the second node, respectively;
• a fifth transistor comprising a gate terminal, a first terminal, and a second terminal coupled to a light emission control line of the light emission control lines, a third node, and an anode of the organic light emitting diode, respectively;
• a first capacitor coupled between the first node and the second node;
• a second capacitor coupled between the second node and the third node;
• and
• a first transistor comprising a gate terminal, a first terminal, and a second terminal coupled to the first node, a first power source, and the third node, respectively, the first transistor being configured to supply a current to the organic light emitting diode.

A method of driving a pixel circuit which comprises:

• an organic light emitting diode;
• a second transistor comprising a gate terminal, a first terminal, and a second terminal coupled to a first scan line, a data line, and a first node, respectively;
• a fourth transistor comprising a gate terminal, a first terminal, and a second terminal coupled to a third scan line, the first node, and a second node, respectively;
• a third transistor comprising a gate terminal, a first terminal, and a second terminal coupled to a second scan line, a reference power source, and the second node, respectively;
• a fifth transistor comprising a gate terminal, a first terminal, and a second terminal coupled to a light emission control line, a third node, and an anode of the organic light emitting diode, respectively;
• a first capacitor coupled between the first node and the second node;
• a second capacitor coupled between the second node and the third node;
• and a first transistor comprising a gate terminal, a first terminal, and a second terminal coupled to the first node, a first power source, and the third node, respectively, the first transistor being configured to supply a current to the organic light emitting diode, the method comprising:
• writing data to the pixel circuit and initializing the pixel circuit by applying a data signal from the data line, and turning on the second, third, and fifth transistors, and turning off the fourth transistor, wherein the second, third, and fifth transistors are turned on by respectively applying a first scan signal, a second scan signal and a light emission control signal each having a first voltage level, and the fourth transistor is turned off by applying a third scan signal having a second voltage level;
• compensating for a threshold voltage of the first transistor by turning off the second transistor, the fourth transistor, and the fifth transistor and turning on the third transistor, wherein the second transistor, the fourth transistor, and the fifth transistor are turned off by respectively applying the first scan signal, the third scan signal, and the light emission control signal each having the second voltage level, and the third transistor is turned on by applying the second scan signal having the first voltage level;
• and
• lighting the organic light emitting diode by turning on the fifth transistor and turning off the second, third, and fourth transistors, wherein the fifth transistor is turned on by applying the light emission control signal having the first voltage level, and the second, third, and fourth transistors are turned off by respectively applying the first scan signal, the second scan signal, and the third scan signal each having the second voltage level.