CN-114360441-B - Variable frequency display device

CN114360441BCN 114360441 BCN114360441 BCN 114360441BCN-114360441-B

Abstract

A display device is provided. The display device includes a pixel connected to each of a first scan line, a second scan line, and a data line, a scan driver supplying the first scan signal to the first scan line and the second scan signal to the second scan line, a controller dividing one frame period into an active period and a blanking period and generating a count signal and a power control signal in which durations of the blanking period are counted, a data driver supplying the data signal to the data line, and a power supply controlling a source driving voltage supplied to the data driver according to the durations of the blanking period based on the power control signal. When the count signal reaches the reference value, the controller supplies a start signal for outputting the first scan signal to the scan driver.

Inventors

JIN JUNHAO
Jin Zhenze
JIN HONGGUI
Pu Henggen
Bai Junxi
Sun Rongxiu
SHEN RONGZHEN
LI SHIGEN

Assignees

三星显示有限公司

Dates

Publication Date: 20260512
Application Date: 20210917
Priority Date: 20200928

Claims (20)

1. A display device, the display device comprising: A pixel connected to each of the first scan line, the second scan line, and the data line; a scan driver configured to supply a first scan signal to the first scan line and a second scan signal to the second scan line; A controller configured to receive a control signal, divide one frame period into an effective period and a blanking period based on the control signal, generate a count signal indicating a duration of the blanking period, and provide a power control signal based on the count signal; a data driver configured to supply a data signal to the data line, and A power supply configured to control at least one of a source driving voltage for the data driver and a gate level voltage for the scan driver based on the power control signal, Wherein the controller supplies a start signal for outputting the first scan signal to the scan driver when the count signal reaches a reference value, Wherein the pixel includes a light emitting element, a first transistor connected between a first driving power source and a second node and including a gate electrode connected to the first node, and a third transistor supplying a reference voltage to the second node in response to the first scan signal supplied to the gate electrode thereof, and Wherein the light emitting element is connected between the second node and a second driving power supply, and the reference voltage is less than or equal to a voltage of the second driving power supply.
2. The display device of claim 1, wherein the reference value is a duration of a first blanking period corresponding to a maximum frame rate of the display device.
3. The display device according to claim 2, wherein: When the frame rate detected based on the control signal is slower than the maximum frame rate, the blanking period includes consecutive first and second blanking periods, and The scan driver supplies the first scan signal to the first scan line in a first period included in the second blanking period based on the start signal.
4. A display device according to claim 3, wherein: the second blanking period includes consecutive first and second periods, Supplying the source driving voltage of a first level in the first blanking period and the first period, and When the supply of the first scan signal in the first period is ended, the source driving voltage is transitioned from the first level to a second level greater than the first level.
5. The display device according to claim 4, wherein: the power supply gradually decreases the source driving voltage from the second level during the second period, and The duration of the second blanking period is less than or equal to the duration of the first blanking period.
6. The display device according to claim 4, wherein the source driving voltage supplied in the effective period immediately after the second blanking period is the same as the source driving voltage at an end time point of the second blanking period.
7. The display device according to claim 6, wherein when a duration of the second blanking period is an integer multiple of the duration of the first blanking period, the source driving voltage supplied in the effective period immediately after the second blanking period has the first level.
8. The display device according to claim 4, wherein the pixel further comprises: A second transistor connected between the data line and the first node and including a gate electrode connected to the second scan line, and A storage capacitor connected between the first node and the light emitting element.
9. The display device of claim 8, wherein the power supply further controls the reference voltage based on the power control signal.
10. The display device according to claim 9, wherein: The reference voltage of the third level is supplied in the first blanking period and the first period, and When the supply of the first scan signal in the first period is ended, the reference voltage transitions from the third level to a fourth level smaller than the third level.
11. The display device according to claim 10, wherein: The power supply gradually increases the reference voltage from the fourth level during the second period, and The duration of the second blanking period is less than or equal to the duration of the first blanking period.
12. The display device according to claim 10, wherein the reference voltage supplied in the effective period immediately after the second blanking period is the same as the reference voltage at an end time point of the second blanking period.
13. The display device according to claim 12, wherein when a duration of the second blanking period is an integer multiple of the duration of the first blanking period, the reference voltage supplied in the effective period immediately after the second blanking period has the third level.
14. The display device according to claim 9, wherein the active period includes a scan period in which the data signal is written to the pixel by turning on the second transistor and the third transistor.
15. A display device according to claim 3, wherein the controller comprises: a frame rate detector that detects the frame rate based on a frame rate variable signal and generates the count signal; a voltage controller for controlling the source driving voltage and a reference voltage supplied to a source electrode of a driving transistor of the pixel in response to the count signal, and And a scan controller outputting the start signal in response to the count signal.
16. A display device, the display device comprising: A pixel connected to a first scan line, a second scan line, and a data line, and including a first transistor that generates a driving current for a light emitting element, wherein the first transistor is connected between a first driving power source and a second node and includes a gate electrode connected to the first node, and a third transistor that supplies a reference voltage to the second node in response to a first scan signal supplied to the gate electrode thereof, the light emitting element is connected between the second node and a second driving power source, and the reference voltage is less than or equal to a voltage of the second driving power source; a scan driver supplying the first scan signal to the first scan line and supplying a second scan signal to the second scan line; A controller dividing one frame period into an effective period and a blanking period based on a control signal supplied from the outside, and generating a count signal and a power control signal in which a time of the blanking period is counted; A data driver for supplying data signals to the data lines, and A power supply controlling at least one of the reference voltage supplied to a source electrode of the first transistor and a gate level voltage supplied to the scan driver according to a duration of the blanking period based on the power control signal, Wherein the scan driver outputs the first scan signal in the blanking period when the count signal reaches a reference value.
17. The display device according to claim 16, wherein the reference value is a duration of a first blanking period corresponding to a maximum frame rate set in the display device.
18. The display device according to claim 17, wherein: When the frame rate detected based on the control signal is slower than the maximum frame rate, the blanking period includes consecutive first and second blanking periods, and The scan driver supplies the first scan signal to the first scan line in a first period included in the second blanking period.
19. The display device of claim 18, wherein: the second blanking period includes consecutive first and second periods, Supplying the reference voltage of a first level in the first blanking period and the first period, and When the supply of the first scan signal in the first period is ended, the reference voltage is transitioned from the first level to a second level smaller than the first level.
20. The display device of claim 19, wherein: The power supply gradually increases the reference voltage from the second level during the second period, and The reference voltage supplied in the effective period immediately after the second blanking period is the same as the reference voltage at the end time point of the second blanking period.

Description

Variable frequency display device The present application claims priority and rights of korean patent application No. 10-2020-0126345 filed in the korean intellectual property office on 9/28 th year 2020, the entire contents of which are incorporated herein by reference. Technical Field The present disclosure relates generally to display devices, and more particularly, to a display device that can change a driving frequency or a frame rate (FRAME RATE). Background The display device may include a pixel unit including a plurality of pixels and a driver for driving the pixels. The driver displays an image in the pixel unit by using an image signal applied from an external graphic processor. The graphic processor generates an image signal by rendering raw data, and a rendering time for generating the image signal corresponding to one frame may vary according to the type or characteristics of an image. The driver may change the frame rate according to the rendering time. The number of times the light emitting element is turned off per unit time (for example, the number of turns off) is changed due to a change in the frame rate, and such a change can be recognized as a change in brightness and/or flickering of an image. Disclosure of Invention Embodiments of the present disclosure provide a display device that may insert an emission off period for supplying a reference voltage to a driving transistor of a pixel into a blanking period and may control a source driving voltage supplied to a data driver based on a duration of the blanking period. Embodiments of the present disclosure provide a display device that may insert an emission off period for supplying a reference voltage to a driving transistor of a pixel into a blanking period, and may control a source driving voltage and/or a reference voltage based on a duration of the blanking period. It will be appreciated that the inventive concept is not limited to the embodiments set forth herein, and that various extensions may be made to the inventive concept without departing from the spirit and scope of the present disclosure. Embodiments of the present disclosure provide a display device including pixels connected to a first scan line, a second scan line, and a data line, a scan driver supplying a first scan signal to the first scan line and a second scan signal to the second scan line, a controller dividing one frame period into an active period and a blanking period based on a control signal supplied from the outside and generating a count signal and a power control signal in which a time of the blanking period is counted, a data driver supplying a data signal to the data line, and a power supply controlling a source driving voltage supplied to the data driver according to a duration of the blanking period based on the power control signal. When the count signal reaches the reference value, the controller may supply a start signal for outputting the first scan signal to the scan driver. The reference value may be a duration of the first blanking period corresponding to a maximum frame rate transmitted to the display apparatus. When the frame rate detected based on the control signal is slower than the maximum frame rate, the blanking period may continuously include a first blanking period and a second blanking period. The scan driver may supply the first scan signal to the first scan line in a first period included in the second blanking period based on the start signal. The second blanking period may include consecutive first and second periods. The source driving voltage of the first level may be supplied in the first blank period and the first period, and when the supply of the first scan signal in the first period is ended, the source driving voltage may be converted from the first level to a second level greater than the first level. The power supply may gradually decrease the source driving voltage from the second level during the second period, and the duration of the second blanking period may be less than or equal to the duration of the first blanking period. The source driving voltage supplied in the effective period immediately after the second blanking period may be the same as the source driving voltage at the end time point of the second blanking period. When the duration of the second blank period is an integer multiple of the duration of the first blank period, the source driving voltage supplied in an effective period immediately after the second blank period may have a first level. The pixel may include a light emitting element, a first transistor connected between a first driving power source and the light emitting element and including a gate electrode connected to a first node, a second transistor connected between a data line and the first node and including a gate electrode connected to a second scan line, a third transistor supplying a reference voltage to the second node in response to a first scan signal supplied to the gate electrod