Light-emitting display
View Patent ↗A pixel circuit of a light-emitting display that reduces the influence of kickback generated by parasitic capacitance. The pixel circuit includes first to fourth transistors, a capacitor, and a light-emitting element. The first and second transistors are serially coupled to each other and turned on in response to a first control signal. The capacitor is coupled in parallel with the first and second transistors. The third transistor supplies a data voltage to a first electrode of the capacitor in response to a select signal. The fourth transistor outputs a current corresponding to its gate-source voltage, which is based on the voltage of the capacitor. The light-emitting element emits light corresponding to the current from the fourth transistor.
1. A light-emitting display, comprising:
a plurality of data lines transmitting a data voltage;
a plurality of scan lines transmitting a select signal; and
a plurality of pixel circuits coupled to the scan lines and the data lines,
wherein a pixel circuit comprises:
a first transistor and a second transistor serially coupled to each other and turned on in response to a first control signal;
a first capacitor coupled in parallel with the first transistor and the second transistor;
a third transistor supplying the data voltage to a first electrode of the first capacitor in response to the select signal;
a fourth transistor outputting a current corresponding to a gate-source voltage of the fourth transistor, the gate-source voltage being based on a voltage of the first capacitor; and
a light-emitting element emitting light in response to the current from the fourth transistor.
2. The light-emitting display of claim 1 ,
wherein a first electrode of the first transistor is coupled to the first electrode of the first capacitor;
wherein a second electrode of the first transistor is coupled to a first electrode of the second transistor; and
wherein a second electrode of the second transistor is coupled to a second electrode of the first capacitor.
3. The light-emitting display of claim 2 , wherein the first transistor and the second transistor are a dual-gate transistor.
4. The light-emitting display of claim 2 , wherein the first transistor and the second transistor have different sizes.
5. The light-emitting display of claim 4 , wherein a channel of the second transistor is longer than a channel of the first transistor.
6. The light-emitting display of claim 1 , wherein the pixel circuit further comprises:
a second capacitor coupled between the first electrode of the first capacitor and a gate of the fourth transistor; and
a first switch diode-connecting the fourth transistor in response to the first control signal,
wherein the gate of the fourth transistor is coupled to a second electrode of the second capacitor, and
wherein a source of the fourth transistor is coupled to a second electrode of the first capacitor.
7. The light-emitting display of claim 6 , wherein the first switch includes a fifth transistor and a sixth transistor serially coupled to each other and turned on in response to the first control signal.
8. The light-emitting display of claim 7 , wherein the fifth transistor and the sixth transistor are a dual-gate transistor.
9. The light-emitting display of claim 8 , wherein the pixel circuit further comprises:
a second switch transmitting the current output from the fourth transistor to the light-emitting element in response to a second control signal,
wherein the second control signal is supplied to the pixel circuit after the first control signal and the select signal.
10. The light-emitting display of claim 1 , wherein the first control signal is a previous select signal that is applied to the pixel circuit before the select signal.
11. The light-emitting display of claim 1 , wherein the light-emitting element uses an organic material to emit light.