# US 2019/0172394 A1 · Driving method of display device and display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0172394 A1 - Document ID: US20190172394A1 - Status: Published application - Kind: A1 - Application number: 16/048,521 - Filed: 2018-07-30 - Published: 2019-06-06 - Earliest claimed: 2017-12-06 - Assignees: Boe Technology Group Co., Ltd. - Applicants: Boe Technology Group Co., Ltd. - Inventors: Yu WANG; Yi CHENG LIN - Web page: https://patentgrep.com/patent/US20190172394A1 ## CPC - G09G 3/3258: with pixel circuitry controlling the voltage across the light-emitting element - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 2320/0233: Improving the luminance or brightness uniformity across the screen - G09G 2320/0295: by monitoring each display pixel - 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 The present disclosure provides a driving method of a display device and a display device. The driving method includes: sensing threshold voltages of the driving transistors of the plurality of pixel units and calculating an external compensation value for display data signal according to the threshold voltages of the driving transistors of the plurality of pixel units; performing an internal compensation on the threshold voltage of the driving transistor through the pixel driving circuit; and superimposing the external compensation value and the display data signal, wherein a data signal obtained by the superimposing is input into the pixel driving circuit for driving the light emitting element to emit light. ## Claims ### Claim 1 A driving method of a display device comprising a plurality of pixel units, each of the pixel units comprising a pixel driving circuit having a driving transistor and a light emitting element coupled to the pixel driving circuit, the driving method comprising: sensing threshold voltages of the driving transistors of the plurality of pixel units and calculating an external compensation value for display data signal according to the threshold voltages of the driving transistors of the plurality of pixel units; performing an internal compensation on the threshold voltage of the driving transistor through the pixel driving circuit; and superimposing the external compensation value and the display data signal, wherein a data signal obtained by the superimposing is input into the pixel driving circuit for driving the light emitting element to emit light. ### Claim 2 (depends on 1) The driving method of a display device according to claim 1, wherein the step of sensing threshold voltages of the driving transistors of the plurality of pixel units and calculating an external compensation value for display data signal according to the threshold voltages of the driving transistors of the plurality of pixel units is performed when image data is not displayed. ### Claim 3 (depends on 1) The driving method of a display device according to claim 1, wherein the step of sensing threshold voltages of the driving transistors of the plurality of pixel units and calculating an external compensation value for display data signal according to the threshold voltages of the driving transistors of the plurality of pixel units is performed in a blank display interval. ### Claim 4 (depends on 1) The driving method of a display device according to claim 1, wherein the step of sensing threshold voltages of the driving transistors of the plurality of pixel units and calculating an external compensation value for display data signal according to the threshold voltages of the driving transistors of the plurality of pixel units is performed when power is off. ### Claim 5 (depends on 1) The driving method of a display device according to claim 1, wherein the driving transistor comprises a first terminal, a second terminal and a control terminal coupled to a first node, a power supply voltage and a second node respectively, and the first node is coupled to the light emitting element, wherein the pixel driving circuit further comprises: a first switch unit, configured to control turning on and off between a data line and the second node; a second switch unit, configured to control turning on and off between a sensing line and the first node; and a capacitor, coupled between the first node and the second node, wherein the step of performing an internal compensation on the threshold voltage of the driving transistor through the pixel driving circuit comprises: turning on the first switch unit and the second switch unit to apply a first reference voltage to the second node through the data line and a second reference voltage to the first node through the sensing line, thereby resetting a voltage of the second node; and maintaining the first switch unit to be turned on and turning off the second switch unit, to keep applying the first reference voltage to the second node through the data line, thereby compensating the threshold voltage of the driving transistor. ### Claim 6 (depends on 5) The driving method of a display device according to claim 5, wherein the step of inputting the data signal obtained by the superimposing to the pixel driving circuit for driving the light emitting element to emit light comprises: maintaining the first switch unit to be turned on and the second switch unit to be turned off, to apply the data signal obtained by superimposing to the second node through the data line; and turning off the first switch unit to drive the light emitting element to emit light. ### Claim 7 (depends on 5) The driving method of a display device according to claim 5, wherein the second reference voltage is 0 v. ### Claim 8 (depends on 5) The driving method of a display device according to claim 5, wherein the step of sensing threshold voltages of the driving transistors of the plurality of pixel units comprises: turning on the first switch unit to apply a sensing voltage through the data line; and maintaining the first switch unit to be turned on and turning on the second switch unit to charge the sense line, thereby obtaining the threshold voltages of the driving transistors. ### Claim 9 A display device comprising a plurality of pixel units, each of the pixel units comprising a pixel driving circuit having a driving transistor and a light emitting element coupled to the pixel driving circuit, wherein the display device further comprising: a sensing module, configured to sense threshold voltages of the driving transistors of the plurality of pixel units and to calculate an external compensation value for display data signal according to the threshold voltages of the driving transistors of the plurality of pixel units; a control module, configured to control the pixel driving circuit to perform an internal compensation on the threshold voltage of the driving transistor; and a superimposing module, configured to superimpose the external compensation value and the display data signal, wherein a data signal obtained by superimposing is input into the pixel driving circuit for driving the light emitting element to emit light. ### Claim 10 (depends on 9) The display device according to claim 9, wherein the driving transistor comprises a first terminal, a second terminal and a control terminal coupled to a first node, a power supply voltage and a second node respectively, and the first node is coupled to the light emitting element, and wherein the pixel driving circuit further comprises: a first switch unit, configured to control turning on and off between a data line and the second node; a second switch unit, configured to control turning on and off between a sensing line and the first node; and a capacitor, coupled between the first node and the second node. ### Claim 11 (depends on 10) The display device according to claim 10, wherein the control module is configured to: turn on the first switch unit and the second switch unit to apply a first reference voltage to the second node through the data line and a second reference voltage to the first node through the sensing line, thereby resetting a voltage of the second node; and maintain the first switch unit to be turned on and turn off the second switch unit, to keep applying the first reference voltage to the second node through the data line, thereby compensating the threshold voltage of the driving transistor. ### Claim 12 (depends on 10) The display device according to claim 10, wherein the superimposing module is configured to: maintain the first switch unit to be turned on and the second switch unit to be turned off, to apply the data signal obtained by superimposing to the second node through the data line; and turn off the first switch unit to drive the light emitting element to emit light. ### Claim 13 (depends on 10) The display device according to claim 10, wherein the sensing module is configured to: turn on the first switch unit to apply a sensing voltage through the data line; and maintain the first switch unit to be turned on and turn on the second switch unit to charge the sense line, thereby obtaining the threshold voltages of the driving transistors.