Display device and method of operating a display device that performs a sensing operation on at least one pixel in a blank period of a frame period
A display device includes a display panel including pixels, and a panel driver configured to sequentially apply data voltages to the pixels on a row basis in an active period of a frame period, and to perform a sensing operation on at least one pixel of the pixels in a blank period of the frame period. Within the blank period, the panel driver applies a pre-charge data voltage to the at least one pixel after the sensing operation, and applies a previous data voltage to the at least one pixel after a predetermined time from a time point at which the pre-charge data voltage is applied.
1. An electronic device comprising:
a processor configured to provide input image data; and
a display device configured to receive the input image data from the processor, and to display an image based on the input image data, the display device comprising:
a display panel including pixels; and
a panel driver configured to sequentially apply data voltages to the pixels on a row basis in an active period of a frame period, and to perform a sensing operation on at least one pixel of the pixels in a blank period of the frame period,
wherein, within the blank period, the panel driver applies a pre-charge data voltage to the at least one pixel after the sensing operation, and applies a previous data voltage to the at least one pixel after a predetermined time from a time point at which the pre-charge data voltage is applied,
wherein the pre-charge data voltage is higher than a maximum gray data voltage.
2. The electronic device of claim 1 , wherein a gate-source voltage of a driving transistor of the at least one pixel after the previous data voltage is applied within the blank period is equal to a gate-source voltage of the driving transistor of the at least one pixel in the active period.
3. The electronic device of claim 1 , wherein the predetermined time corresponds to a blank emission period in which the at least one pixel emits light within the blank period.
4. The electronic device of claim 1 , wherein the previous data voltage is a data voltage that is applied to the at least one pixel in the active period.
5. The electronic device of claim 1 , wherein the at least one pixel includes:
a driving transistor including a gate coupled to a gate node, a first terminal coupled to a line having a first power supply voltage, and a second terminal coupled to a source node;
a scan transistor including a gate receiving a scan signal, a first terminal coupled to a data line, and a second terminal coupled to the gate node;
a sensing transistor including a gate receiving a sensing signal, a first terminal coupled to a sensing line, and a second terminal coupled to the source node;
a storage capacitor including a first electrode coupled to the gate node, and a second electrode coupled to the source node; and
a light emitting element including an anode coupled to the source node, and a cathode coupled to a line having a second power supply voltage.
6. The electronic device of claim 5 , wherein, within the predetermined time, the driving transistor is turned on, and a voltage of the source node is increased to a voltage greater than or equal to a threshold voltage of the light emitting element.
7. The electronic device of claim 5 , wherein, within the predetermined time, a parasitic capacitor of the light emitting element is charged.
8. The electronic device of claim 5 , wherein the blank period includes:
a sensing initialization period in which a sensing data voltage is applied to the gate node, and an initialization voltage is applied to the source node;
a sensing period in which the sensing operation is performed;
a pre-charge data application period in which the pre-charge data voltage is applied to the gate node, and the initialization voltage is applied to the source node;
a blank emission period in which the light emitting element emits light; and
a recovery data application period in which the previous data voltage is applied to the gate node, and the initialization voltage is applied to the source node.
9. The electronic device of claim 8 , wherein, in the sensing initialization period,
the scan signal has an on-level, and the sensing signal has the on-level,
the scan transistor is turned on in response to the scan signal having the on-level, and transfers the sensing data voltage of the data line to the gate node, and
the sensing transistor is turned on in response to the sensing signal having the on-level, and transfers the initialization voltage of the sensing line to the source node.
10. The electronic device of claim 8 , wherein, in the sensing period,
the scan signal has an off-level, and the sensing signal has an on-level,
the scan transistor is turned off in response to the scan signal having the off-level,
the sensing transistor is turned on in response to the sensing signal having the on-level, and couples the source node to the sensing line,
the driving transistor generates a sensing current based on the sensing data voltage, and
the panel driver senses the sensing current through the sensing line.
11. The electronic device of claim 8 , wherein, in the pre-charge data application period,
the scan signal has an on-level, and the sensing signal has the on-level,
the scan transistor is turned on in response to the scan signal having the on-level, and transfers the pre-charge data voltage of the data line to the gate node, and
the sensing transistor is turned on in response to the sensing signal having the on-level, and transfers the initialization voltage of the sensing line to the source node.
12. The electronic device of claim 8 , wherein, in the blank emission period,
the scan signal has an off-level, and the sensing signal has the off-level,
the scan transistor is turned off in response to the scan signal having the off-level,
the sensing transistor is turned off in response to the sensing signal having the off-level,
the driving transistor generates a driving current based on the pre-charge data voltage,
a voltage of the source node is increased to a voltage greater than or equal to a threshold voltage of the light emitting element, and
a voltage of the gate node is increased as the voltage of the source node is increased.
13. The electronic device of claim 8 , wherein, in the recovery data application period,
the scan signal has an on-level, and the sensing signal has the on-level,
the scan transistor is turned on in response to the scan signal having the on-level, and transfers the previous data voltage of the data line to the gate node, and
the sensing transistor is turned on in response to the sensing signal having the on-level, and transfers the initialization voltage of the sensing line to the source node.
14. The electronic device of claim 8 , wherein a voltage difference between a voltage of the gate node and a voltage of the source node after the recovery data application period is equal to a voltage difference between the voltage of the gate node and the voltage of the source node in the active period.
15. A method of operating a display device, the method comprising:
sequentially applying data voltages to pixels on a row basis in an active period of a frame period;
performing a sensing operation on at least one pixel of the pixels in a blank period of the frame period;
applying a pre-charge data voltage to the at least one pixel after the sensing operation within the blank period; and
applying a previous data voltage to the at least one pixel after a predetermined time from a time point at which the pre-charge data voltage is applied within the blank period,
wherein the predetermined time corresponds to a blank emission period in which the at least one pixel emits light within the blank period.
16. The method of claim 15 , wherein a gate-source voltage of a driving transistor of the at least one pixel after the previous data voltage is applied within the blank period is equal to a gate-source voltage of the driving transistor of the at least one pixel in the active period.
17. The method of claim 15 , wherein the pre-charge data voltage is higher than a maximum gray data voltage.
18. The method of claim 15 , wherein the previous data voltage is a data voltage that is applied to the at least one pixel in the active period.