# US 10,121,410 B2 · Power efficient adaptive panel pixel charge scheme > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,121,410 B2 - Document ID: US10121410B2 - Status: Granted - Kind: B2 - Application number: 14/487,020 - Filed: 2014-09-15 - Published: 2015-12-17 - Granted: 2018-11-06 - Earliest claimed: 2014-06-13 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Fenghua Zheng; Sandro H. Pintz - Web page: https://patentgrep.com/patent/US10121410B2 ## CPC - G09G 3/3216: using a passive matrix - G09G 3/2007: {Display of intermediate tones} - G09G 2310/0221: with use of split matrices (G09G3/3644 and G09G3/3666 take precedence) - G09G 2310/027: Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters - G09G 2310/0291: Details of output amplifiers or buffers arranged for use in a driving circuit - G09G 2330/021: Power management, e.g. power saving - G09G 2340/16: Determination of a pixel data signal depending on the signal applied in the previous frame - 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 This application relates to systems, methods, and apparatus for reducing the power consumption of a display panel. Specifically, the embodiments discussed herein relate to a panel pixel charge scheme that allows the current output of a display driver to be modified based on the content to be displayed at the display panel. The display driver can compare current and upcoming display content in order to determine how the line voltage for one or more output lines will change over time. If, based on the comparison, the voltage for an output line is not going to vary substantially over time, the bias current output from the display driver can be modified in order to save power. The modification to the bias current can depend on the amount of change the line voltage will undergo in subsequent executions of the content data. ## Claims ### Claim 1 A method for providing a data line output from a display driver of a display device having a display panel, the method comprising: receiving, at the display driver, at least one bit of current display content for display with a current row line of the display panel; receiving, at the display driver, at least one bit of future display content for display with a subsequent row line of the display panel; and providing a modified bias current of the display driver according to a line charge differential for the current row line and the subsequent row line determined based on a comparison between the at least one bit of the current display content for display with the current row line and the at least one bit of the subsequent future display content for display with the subsequent row line. ### Claim 2 (depends on 1) The method as in claim 1, further comprising: executing, after the current display content is executed with the current row line, the future display content with the subsequent row line concurrently with outputting the modified bias current from the display driver. ### Claim 3 (depends on 1) The method as in claim 1, further comprising: providing a bias current to a first light emitting diode (LED) of the display panel corresponding to the current display content, and subsequently providing the modified bias current to a second LED of the display panel corresponding to the future display content. ### Claim 4 (depends on 3) The method as in claim 3, wherein a ratio of the bias current and the modified bias current is substantially proportional to the line charge differential. ### Claim 5 (depends on 1) The method as in claim 1, further comprising: comparing a most significant bit (MSB) of both the current display content and the future display content. ### Claim 6 (depends on 1) The method as in claim 1, further comprising: comparing the line charge differential to one or more adjustment thresholds, wherein each of the one or more adjustment thresholds corresponds to a proportion value for adjusting a bias current output of the display driver. ### Claim 7 (depends on 1) The method as in claim 1, further comprising: providing the modified bias current by reducing a normal bias current by approximately 50 percent when the line charge differential is approximately zero, wherein the normal bias current corresponds to the normal bias current associated with the future display content. ### Claim 8 A system for reducing power consumption of a display device having a display panel, based on content data to be displayed with the display panel of the display device, the system comprising: a display driver electrically coupled to a data input unit and to at least one data line of the display panel, wherein the display driver is configured to: receive, from the data input unit, current content data and future content data to be respectively displayed using two different row lines of the display panel; and modify a bias current output of the display driver when the current content data and the future content data provided by the data input unit is indicative of a charge differential between the two row lines that is within one or more charge differential thresholds accessible to the display driver. ### Claim 9 (depends on 8) The system as in claim 8, wherein the one or more charge differential thresholds correspond to a voltage difference of the at least one data line of the display driver. ### Claim 10 (depends on 9) The system as in claim 9, wherein the voltage difference is a difference between a first voltage of the at least one data line when the current content data is executed using a first one of the two row lines, and a second voltage of the at least one data line when the future content data is executed using a second one of the two row lines. ### Claim 11 (depends on 8) The system as in claim 8, wherein the current content data includes a first data array and the future content data includes a second data array, wherein the display driver is configured to execute the second data array subsequent to the first data array. ### Claim 12 (depends on 8) The system as in claim 8, wherein the one or more charge differential thresholds correspond to a percentage that the bias current output can be increased or decreased by depending on the charge differential indicated by the current content data and the future content data. ### Claim 13 (depends on 8) The system as in claim 8, wherein the current content data and the future content data includes at least two arrays of bits, and the display driver is configured to compare at least one bit of each of the least two arrays of bits to determine the charge differential. ### Claim 14 (depends on 13) The system as in claim 13, wherein the display driver is further configured to reduce the bias current output when the charge differential is substantially zero. ### Claim 15 A display driver directly coupled to a plurality of data lines of a display panel and configured to reduce power consumption by the display panel having at least a first row line and a second row line, based on content data to be displayed by the display panel, the display driver comprising: a current output unit; and a data control unit configured to: determine a modified bias current for the current output unit based on a voltage differential generated by sequentially comparing a current content value to a future content value, wherein the second future content value variable is arranged to be executed for display by the display panel using the second row line of the display panel subsequent to execution of the current content value for display by the display panel using the first row line of the display panel. ### Claim 16 (depends on 15) The display driver as in claim 15, wherein the current output unit is configured to provide the modified bias current to at least one of the plurality of data lines of the display panel subsequent to the voltage differential being generated at the data control unit. ### Claim 17 (depends on 15) The display driver as in claim 15, wherein sequentially comparing the current content value to the future content value includes comparing a most significant bit (MSB) of each of the current content value to the future content value. ### Claim 18 (depends on 15) The display driver of claim 15, wherein the modified bias current is less than a normal bias current associated with the current content value when the current content value is equal to the future content value. ### Claim 19 (depends on 15) The display driver as in claim 15, wherein the future content value is associated with a normal bias current that is adjusted according to the voltage differential in order to provide the modified bias current. ### Claim 20 (depends on 19) The display driver as in claim 19, wherein the data control unit is further configured to: compare the voltage differential to one or more adjustment thresholds, and adjust the normal bias current according to the one or more adjustment thresholds.