Pixel, stage circuit and organic light emitting display device having the pixel and the stage circuit

A pixel, comprising:

• an organic light emitting diode;
• a first transistor to control an amount of driving current flowing from a first driving power supply coupled to a first electrode, through the organic light emitting diode, and to a second driving power supply based on a voltage of a first node;
• a second transistor coupled between the first node and a second electrode of the first transistor, the second transistor is to turn on when a first scan signal is supplied to a first scan line;
• a storage capacitor coupled between the first node and a second node;
• a third transistor coupled between a data line and the second node, the third transistor to turn on when a second scan signal is supplied to a second scan line;
• and
• a fourth transistor coupled between the second node and an initialization power supply, the fourth transistor to turn off when an inverted light emission control signal is supplied to an inverted light emission control line, wherein the first transistor is a p-type LTPS thin film transistor and the third transistor and the fourth transistor are n-type oxide semiconductor thin film transistor, wherein:
• all transistors directly connected to a gate electrode of the first transistor are oxide semiconductor thin film transistors, and
• all transistors coupled to the first transistor and through which the driving current flows are LTPS thin film transistors.

An organic light emitting display device, comprising:

• pixels connected to scan lines, light emission control lines, and data lines;
• a scan driver to drive the scan lines and the light emission control lines;
• and
• a data driver to drive the data lines, wherein at least one pixel in a horizontal line, among the pixels, includes:
• an organic light emitting diode;
• a first transistor having a first electrode coupled to a first node and a second electrode coupled to an anode electrode of the organic light emitting diode, wherein the first transistor is to control an amount of driving current flowing from a first driving power supply coupled to the first node, through the organic light emitting diode, and to a second driving power supply;
• a second transistor coupled between a data line and the first node, the second transistor to turn on when a first scan signal is supplied to a first scan line;
• a third transistor coupled between a gate electrode and the second electrode of the first transistor, the third transistor to turn on when a second scan signal is supplied to a second scan line;
• and
• a fourth transistor coupled between the gate electrode of the first transistor and an initialization power supply, the fourth transistor to turn on when a third scan signal is supplied to a third scan line, wherein the first transistor is a Low Temperature Poly-Silicon (LTPS) thin film transistor and the third transistor and the fourth transistor are oxide semiconductor thin film transistors, wherein
• all transistors directly connected to the gate electrode of the first transistor are oxide semiconductor thin film transistors, and
• all transistors coupled to the first transistor and through which the driving current flows are LTPS thin film transistors.