# US 12,223,883 B2 · Display device and method for driving the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,223,883 B2 - Document ID: US12223883B2 - Status: Granted - Kind: B2 - Application number: 18/139,113 - Filed: 2023-04-25 - Published: 2024-01-18 - Granted: 2025-02-11 - Earliest claimed: 2022-07-18 - Assignees: Samsung Display Co., Ltd.; Iucf-Hyu (Industry-University Cooperation Foundation Hanyang University) - Applicants: Samsung Display Co., LTD.; IUCF-HYU (Industry-University Cooperation Foundation Hanyang University) - Inventors: Byungchang Yu; Oh-Kyong Kwon; Kyunghoon Chung - Web page: https://patentgrep.com/patent/US12223883B2 ## CPC - G09G 3/32: semiconductive, e.g. using light-emitting diodes [LED] - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 2300/0819: used for counteracting undesired variations, e.g. feedback or autozeroing - G09G 2300/0852: being a dynamic memory with more than one capacitor - G09G 2300/0861: with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes - G09G 2310/0251: Precharge or discharge of pixel before applying new pixel voltage - G09G 2310/0267: Details of drivers for scan electrodes, other than drivers for liquid crystal, plasma or OLED displays - G09G 2320/0233: Improving the luminance or brightness uniformity across the screen - G09G 2320/0247: Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes - G09G 2330/028: Generation of voltages supplied to electrode drivers in a matrix display other than LCD - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) ## Abstract A display device includes: a pixel including a light emitting element, a first capacitor connected between a first node and a second node, and a second capacitor connected between the second node and a third node. The pixel further includes: a first transistor connected between the second node and the light emitting element to operate depending on potential of the first node; a second transistor connected between the third node and a data line to operate depending on a first scan signal; a third transistor connected between the third node and the second transistor to operate depending on a light emitting control signal; a fourth transistor connected between a reference voltage line and a first node to operate depending on the second scan signal; and a fifth transistor connected between the reference voltage line and the third node to operate depending on a third scan signal. ## Claims ### Claim 1 A display device comprising: a display panel including a pixel; and a panel driver configured to drive the display panel, wherein the pixel includes: a light emitting element; a first capacitor including a first electrode connected to a first node and a second electrode connected to a second node; a second capacitor including a first electrode connected to the second node and a second electrode connected to a third node; a first transistor including a first electrode connected to the second node, a second electrode connected to the light emitting element, and a gate electrode connected to the first node; a second transistor connected between the second electrode of the second capacitor and a data line, and configured to operate depending on a first scan signal provided from the panel driver; a third transistor connected between the second electrode of the second capacitor and the second transistor, and configured to operate depending on a first light emitting control signal provided from the panel driver; a fourth transistor connected between a reference voltage line, which is to receive a reference voltage, and the first electrode of the first capacitor, and configured to operate depending on a second scan signal provided from the panel driver; and a fifth transistor connected between the reference voltage line and the second electrode of the second capacitor, and configured to operate depending on a third scan signal provided from the panel driver, wherein the second scan signal has an activation level for a first period, and the first light emitting control signal has a deactivation level for the first period. ### Claim 2 (depends on 1) The display device of claim 1, wherein the pixel further includes: a sixth transistor connected between a first voltage line, which is to receive a first driving voltage, and the second node, and configured to operate depending on a second light emitting control signal; and a seventh transistor connected between the reference voltage line and the light emitting element, and configured to operate depending on a fourth scan signal. ### Claim 3 (depends on 2) The display device of claim 2, wherein the first scan signal, the second scan signal, the third scan signal, and the fourth scan signal have the activation level for the first period, the first light emitting control signal has the deactivation level for the first period, and the second light emitting control signal has the activation level for the first period. ### Claim 4 (depends on 3) The display device of claim 3, wherein the first scan signal, the second scan signal, the third scan signal, and the fourth scan signal have the activation level for a second period subsequent to the first period, and the first light emitting control signal and the second light emitting control signal has the deactivation level for the second period, and wherein a duration of the second period is longer than a duration of the first period. ### Claim 5 (depends on 4) The display device of claim 4, wherein the first scan signal, the second scan signal, and the fourth scan signal have the activation level for a third period subsequent to the second period, the third scan signal has the deactivation level for the third period, the first light emitting control signal has the activation level for the third period, and the second light emitting control signal has the deactivation level for the third period. ### Claim 6 (depends on 5) The display device of claim 5, wherein the first scan signal, the second scan signal, and the fourth scan signal are a same signal, wherein the third scan signal is activated earlier than the first scan signal, the second scan signal, and the fourth scan signal, by a duration of the first period, and wherein the first light emitting control signal is deactivated earlier than the second light emitting control signal by a duration of the third period. ### Claim 7 (depends on 2) The display device of claim 2, wherein the pixel further includes: an eighth transistor diode-connected between the first voltage line and the first node. ### Claim 8 (depends on 2) The display device of claim 2, wherein the light emitting element is connected between a second voltage line, which is to receive a second driving voltage, and the first transistor. ### Claim 9 (depends on 2) The display device of claim 2, wherein the display panel displays an image during a plurality of frames, wherein at least one frame of the plurality of frames includes a write period and a holding period, wherein the first scan signal, the second scan signal, and the third scan signal have an activation level within the write period, and has a deactivation level during the holding period, and wherein the first light emitting control signal and the second light emitting control signal has the activation level within the write period and the holding period. ### Claim 10 (depends on 9) The display device of claim 9, wherein the reference voltage has a reference level during the write period, and is varied to be in a level higher than the reference level within the holding period. ### Claim 11 (depends on 10) The display device of claim 10, wherein the reference voltage is varied in a level range higher than the reference level during the holding period and lower than the first driving voltage during the holding period. ### Claim 12 (depends on 9) The display device of claim 9, wherein the reference voltage has a reference level during the write period, and is maintained to the reference level during the holding period. ### Claim 13 (depends on 1) The display device of claim 1, wherein the panel driver includes: a scan driving circuit configured to output the first scan signal, the second scan signal, and the third scan signal; and a light emitting driving circuit configured to output the first light emitting control signal, and wherein the light emitting driving circuit operates at a frequency equal to or higher than a frequency of the scan driving circuit. ### Claim 14 (depends on 13) The display device of claim 13, wherein the panel driver further includes: a voltage generator configured to adjust a voltage level of the reference voltage depending on an operating frequency of the scan driving circuit. ### Claim 15 A display device comprising: a display panel including a pixel; and a panel driver configured to drive the display panel, wherein the pixel includes: a light emitting element; a first capacitor connected between a first node and a second node; a second capacitor connected between the second node and a third node; a first transistor connected between the second node and the light emitting element, and configured to operate depending on potential of the first node; a second transistor connected between the third node and a data line, and configured to operate depending on a first scan signal provided from the panel driver; a third transistor connected between the third node and the second transistor, and configured to operate depending on a first light emitting control signal provided from the panel driver; a fourth transistor connected between a reference voltage line, which is to receive a reference voltage, and the first node, and configured to operate depending on a second scan signal provided from the panel driver; and a fifth transistor connected between the reference voltage line and the third node, and configured to operate depending on a third scan signal provided from the panel driver, wherein the first scan signal, the second scan signal, and the third scan signal have an activation level for a first period, and wherein the first light emitting control signal has a deactivation level for the first period. ### Claim 16 (depends on 15) The display device of claim 15, wherein the first scan signal is a same signal as the second scan signal, and wherein the third scan signal is activated earlier than the first scan signal and the second scan signal, by a duration of the first period. ### Claim 17 A display device comprising: a display panel including a pixel; and a panel driver configured to drive the display panel, wherein the pixel includes: a light emitting element; a first capacitor connected between a first node and a second node; a second capacitor connected between the second node and a third node; a first transistor connected between the second node and the light emitting element, and configured to operate depending on potential of the first node; a second transistor connected between the third node and a data line, and configured to operate depending on a first scan signal provided from the panel driver; and a fourth transistor connected between a reference voltage line, which is to receive a reference voltage, and the first node, and configured to operate depending on a second scan signal provided from the panel driver, wherein the display panel displays an image during a plurality of frames, and at least one frame of the plurality of frames includes a write period and a holding period, and wherein the reference voltage has a reference level during the write period, and is varied to be in a level higher than the reference level within the holding period. ### Claim 18 (depends on 17) The display device of claim 17, wherein the pixel further includes: a third transistor connected between the third node and the second transistor, and configured to operate depending on a first light emitting control signal provided from the panel driver; a fifth transistor connected between the reference voltage line and the third node, and configured to operate depending on a third scan signal provided from the panel driver; and a sixth transistor connected between a first voltage line, which is to receive a first driving voltage, and the second node, and configured to operate depending on a second light emitting control signal. ### Claim 19 (depends on 18) The display device of claim 18, wherein the reference voltage is varied in a level range higher than the reference level during the holding period and lower than a level of the first driving voltage during the holding period. ### Claim 20 (depends on 17) The display device of claim 17, wherein the first scan signal, and the second scan signal have an activation level within the write period, and has a deactivation level during the holding period. ### Claim 21 A method for driving a display device including a display panel including a pixel connected to a reference voltage line which is to receive a reference voltage, and a panel driver which drives the display panel during a plurality of frames, at least one frame of which includes a write period and a holding period, the method comprising: applying, to the pixel, a scan signal having an activation level within a non-emission period of the write period; applying, to the pixel, a light emitting control signal having the activation level within an emission period of the write period; and deactivating the scan signal within the holding period, and applying the light emitting control signal to the pixel within the emission period of the holding period, wherein the reference voltage has a reference level during the write period, and is varied to be in a level higher than the reference level during the holding period. ### Claim 22 (depends on 21) The method of claim 21, wherein the pixel includes: a light emitting element; a first capacitor connected between a first node and a second node; a second capacitor connected between the second node and a third node; a first transistor connected between the second node and the light emitting element, and configured to operate depending on potential of the first node; a second transistor connected between the third node and a data line, and configured to operate depending on a first scan signal of the scan signal; and a fourth transistor connected between the reference voltage line and the first node, and configured to operate depending on a second scan signal of the scan signal. ### Claim 23 (depends on 22) The method of claim 22, wherein the pixel further includes: a third transistor connected between the third node and the second transistor, and configured to operate depending on a first light emitting control signal of the light emitting control signal; a fifth transistor connected between the reference voltage line and the third node, and configured to operate depending on a third scan signal of the scan signal; and a sixth transistor connected between a first voltage line, which is to receive a first driving voltage, and the second node, and configured to operate depending on a second light emitting control signal of the light emitting control signal. ### Claim 24 (depends on 23) The method of claim 23, wherein the reference voltage is varied in a level range higher than the reference level and lower than a level of the first driving voltage during the holding period. ### Claim 25 (depends on 23) The method of claim 23, wherein the first scan signal, the second scan signal, and the third scan signal have an activation level within the write period, and has a deactivation level during the holding period, and wherein the first light emitting control signal and the second light emitting control signal have the activation level during the write period and the holding period. ### Claim 26 (depends on 21) The method of claim 21, wherein a total number of holding periods included in each of the at least one frame is adjusted depending on an operating frequency of the display panel. ### Claim 27 (depends on 26) The method of claim 26, wherein the pixel is provided in plurality, and wherein the method further includes: measuring a light emitting current at the operating frequency with respect to sample pixels selected from the plurality of pixels; modulating image data by using a difference between the measured light emitting current and a preset target current corresponding to the operating frequency, and generating a data signal based on the modulated image data; and applying the data signal to a relevant pixel of the plurality of pixels, within the non-emission period of the write period.