Pixel circuit having in-pixel compensation function
A pixel circuit includes a light emitting element, a first driver transistor, a second driver transistor, and a first compensation capacitor. A first terminal of the first driving transistor is configured to receive a power signal, and a second terminal of the first driving transistor is electrically coupled to the light emitting element. A first terminal of the second driving transistor receives the power signal, and a control terminal of the second driving transistor is electrically coupled to the light emitting element. The first compensation capacitance is electrically coupled to a control terminal of the first driving transistor and the second terminal of the second driving transistor, respectively.
1. A pixel circuit, comprising:
a light emitting element;
a first driver transistor comprising a first terminal, a second terminal and a control terminal, wherein the second terminal of the first driving transistor is electrically connected to the light emitting element;
a second driver transistor comprising a first terminal, a second terminal and a control terminal, wherein the control terminal of the second driving transistor is electrically connected to the light emitting element; and
a first compensation capacitor electrically connected to the control terminal of the first driving transistor and the second terminal of the second driving transistor, and a compensation node between the first compensation capacitor and the second driving transistor;
wherein the control terminal of the first driver transistor is configured to receive a data signal in a data input period;
wherein a voltage of the compensation node is substantially twice a voltage of the control terminal of the second driving transistor in a compensation period.
2. The pixel circuit of claim 1 , wherein when in a reset period, the first driver transistor is turned on, the first terminal of the first driver transistor is configured to receive a low voltage signal, and the second driver transistor is turned on.
3. The pixel circuit of claim 2 , wherein when in the reset period, a voltage of the compensation node is discharged to a sum of a threshold voltage value of the first driving transistor and a threshold voltage value of the second driving transistor.
4. The pixel circuit of claim 1 , further comprising:
a second compensation capacitor respectively electrically connected to the control terminal of the first driver transistor and a reference voltage source, wherein when in a data input period, the first driver transistor is turned off, and the first compensation capacitor and the second compensation capacitor change a voltage value of the compensation node according to the Capacitive coupling effect in order to turn on the second driver transistor.
5. The pixel circuit of claim 4 , wherein when in the compensation period, both of the first driver transistor and the second driver transistor are turned on, and a voltage value of the control terminal of the first driver transistor is decreased corresponding to a voltage change of the compensation node according to the capacitive coupling effect between the first compensation capacitor and the second compensation capacitor.
6. The pixel circuit of claim 1 , further comprising:
a transistor switch comprising a first terminal, a second terminal and a control terminal, wherein in the data input period, the first terminal of the transistor switch is configured to receive a data signal, the second terminal of the transistor switch is electrically connected to the control terminal of the first driving transistor.
7. The pixel circuit of claim 6 , wherein in a reset period, the transistor switch is turn on.
8. The pixel circuit of claim 7 , wherein in a lighting period, both of the first driver transistor and the second driver transistor are turned on, and the transistor switch is turned off.
9. The pixel circuit of claim 8 , wherein the reset period, the data input period, the compensation period, and the lighting period are sequentially arranged.