# US 2019/0244576 A1 · Display controller with multiple common voltages corresponding to multiple refresh rates > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0244576 A1 - Document ID: US20190244576A1 - Status: Published application - Kind: A1 - Application number: 16/313,401 - Filed: 2016-07-01 - Published: 2019-08-08 - Earliest claimed: 2016-07-01 - Assignees: Intel Corporation - Applicants: Intel Corporation - Inventors: Dongyeung Kwak; Ramon C. Cancel Olmo; Jue Li; Thomas A. Nugraha; John Lang - Web page: https://patentgrep.com/patent/US20190244576A1 ## CPC - G09G 3/3655: {Details of drivers for counter electrodes, e.g. common electrodes for pixel capacitors or supplementary storage capacitors} - G09G 3/3614: {Control of polarity reversal in general} - G09G 2310/08: Details of timing specific for flat panels, other than clock recovery - G09G 2320/0247: Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes - G09G 2320/0252: Improving the response speed - G09G 2340/0435: Change or adaptation of the frame rate of the video stream - G09G 2370/08: Details of image data interface between the display device controller and the data line driver circuit - 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 controller for a display may include a frame rate circuit to change a frame rate of the display from a first frame rate to a second frame rate, and a reference voltage circuit to adjust a reference voltage of the display from a first reference voltage corresponding to the first frame rate to a second reference voltage corresponding to the second frame rate. The display may be a thin film transistor liquid crystal display. The reference voltage may correspond to a common voltage (Vcom) for the display. ## Claims ### Claim at position 1 1-24. (canceled) ### Claim 25 A liquid crystal display system, comprising: a liquid crystal display panel; a source driver circuit coupled to the liquid crystal display panel; a gate driver circuit coupled to the liquid crystal display panel; a display connector; a back light disposed adjacent to the liquid crystal display panel; a back light driver circuit coupled between the display connector and the back light; a timing control circuit coupled between the display connector and the source driver circuit, the timing control circuit to set a frame rate of the liquid crystal display panel to one of at least a first frame rate and a second frame rate in accordance with an operation mode; and a power control circuit coupled between the display connector and the gate driver circuit, the power control circuit to set a reference voltage of the liquid crystal display panel to one of at least a first reference voltage and a second reference voltage in accordance with the operation mode, wherein the first reference voltage corresponds to a first pre-determined voltage for the first frame rate and the second reference voltage corresponds to a second pre-determined voltage for the second frame rate. ### Claim 26 (depends on 25) The liquid crystal display system of claim 25, further comprising: a non-volatile memory storing at least a first value which correlates the first reference voltage with the first frame rate and at least a second value which correlates the second reference voltage with the second frame rate. ### Claim 27 (depends on 26) The liquid crystal display system of claim 26, wherein the timing control circuit includes a frame rate circuit to set a different frame rate for the liquid crystal display to one of the first frame and the second frame rate in accordance with a change in the operation mode, to retrieve one of the first value and the second value from the non-volatile memory in accordance with the different frame rate, and to provide the retrieved value to the power control circuit. ### Claim 28 (depends on 27) The liquid crystal display system of claim 27, wherein the first reference voltage corresponds to a voltage which provides reduced flicker at the first frame rate and the second reference voltage corresponds to a voltage which provides reduced flicker at the second frame rate. ### Claim 29 A processing system comprising; a processor; a display coupled to the processor; and a display controller coupled to the display, wherein the display controller includes a frame rate circuit to change a frame rate of a display from a first frame rate to a second frame rate, and a reference voltage circuit to adjust a reference voltage of the display from a first reference voltage corresponding to the first frame rate to a second reference voltage corresponding to the second frame rate. ### Claim 30 (depends on 29) The processing system of claim 29, wherein the display controller further comprises: a memory storing a first value which correlates the first reference voltage with the first frame rate in a first memory location and a second value which correlates the second reference voltage with the second frame rate in a second memory location. ### Claim 31 (depends on 30) The processing system of claim 30, wherein the first reference voltage corresponds to a voltage which provides reduced flicker at the first frame rate and the second reference voltage corresponds to a voltage which provides reduced flicker at the second frame rate. ### Claim 32 (depends on 29) The processing system of claim 29, wherein the frame rate circuit is further to change the frame rate of the display from the first frame rate to the second frame rate in accordance with a change in an operation mode and the reference voltage circuit is further to adjust the reference voltage of the display from the first reference voltage to the second reference voltage in accordance with the change in the operation mode. ### Claim 33 (depends on 32) The processing system of claim 32, wherein the change in the operation mode corresponds to a change in a power mode. ### Claim 34 (depends on 29) The processing system of claim 29, wherein the frame rate circuit is further to change the frame rate of the display from the first frame rate to a third frame rate, and wherein the reference voltage circuit is further to adjust the reference voltage of the display from the first reference voltage corresponding to the first frame rate to a third reference voltage corresponding to the third frame rate. ### Claim 35 (depends on 29) The processing system of claim 29, wherein the display comprises a liquid crystal display and wherein the reference voltage corresponds to a common voltage for the liquid crystal display. ### Claim 36 A display controller comprising: a frame rate circuit to change a frame rate of a display from a first frame rate to a second frame rate; and a reference voltage circuit to adjust a reference voltage of the display from a first reference voltage corresponding to the first frame rate to a second reference voltage corresponding to the second frame rate. ### Claim 37 (depends on 36) The display controller of claim 36, further comprising: a memory storing a first value which correlates the first reference voltage with the first frame rate in a first memory location, and a second value which correlates the second reference voltage with the second frame rate in a second memory location. ### Claim 38 (depends on 37) The display controller of claim 37, wherein the first reference voltage corresponds to a voltage which provides reduced flicker at the first frame rate and the second reference voltage corresponds to a voltage which provides reduced flicker at the second frame rate. ### Claim 39 (depends on 36) The display controller of claim 36, wherein the frame rate circuit is further to change the frame rate of the display from the first frame rate to the second frame rate in accordance with a change in an operation mode and the reference voltage circuit is further to adjust the reference voltage of the display from the first reference voltage to the second reference voltage in accordance with the change in the operation mode. ### Claim 40 (depends on 39) The display controller of claim 39, wherein the change in the operation mode corresponds to a change in a power mode. ### Claim 41 (depends on 36) The display controller of claim 36, wherein the frame rate circuit is further to change the frame rate of the display from the first frame rate to a third frame rate, and wherein the reference voltage circuit is further to adjust the reference voltage of the display from the first reference voltage corresponding to the first frame rate to a third reference voltage corresponding to the third frame rate. ### Claim 42 A method of controlling a display, comprising: changing a frame rate of the display from a first frame rate to a second frame rate; and adjusting a reference voltage of the display from a first reference voltage corresponding to the first frame rate to a second reference voltage corresponding to the second frame rate. ### Claim 43 (depends on 42) The method of claim 42, further comprising: retrieving a value from a memory location which correlates the second reference voltage with the second frame rate. ### Claim 44 (depends on 43) The method of claim 43, wherein changing the frame rate of the display from the first frame rate to the second frame rate comprises: changing an operation mode; and changing the frame rate of the display from the first frame rate to the second frame rate in accordance with the operation mode. ### Claim 45 (depends on 44) The method of claim 44, wherein changing the operation mode comprises changing a power mode. ### Claim 46 (depends on 42) The method of claim 42, further comprising: changing the frame rate of the display from the first frame rate to a third frame rate; and adjusting the reference voltage of the display from the first reference voltage corresponding to the first frame rate to a third reference voltage corresponding to the third frame rate. ### Claim 47 (depends on 42) The method of claim 42, further comprising: determining the second reference voltage in accordance with a voltage level which provides reduced flicker at the second frame rate. ### Claim 48 (depends on 47) The method of claim 47, further comprising: storing a value which correlates the second reference voltage with the second frame rate in a memory.