Display driver and displaying method for cascade application

Abstract

A display driver that includes a first driver integrated circuit being cascaded to a second driver integrated circuit is introduced. The first driver integrated circuit includes a first gamma voltage generator that is configured to output a plurality of first gamma voltages to output terminals of the first gamma voltage generator. The second driver integrated circuit includes a second gamma voltage generator that is configured to output a plurality of second gamma voltages to output terminals of the second gamma voltage generator. Each of the output terminals of the first gamma voltage generator is corresponded to one of the output terminals of the second gamma voltage generator. At least one of the output terminals of the first gamma voltage generator is electrically coupled to the corresponding one of the output terminals of the second gamma voltage generator to output at least one common gamma voltage of the first gamma voltages and the second gamma voltages. A method adapted to the display driver is also introduced.

What is claimed is: 
     
       1. A display driver, comprising:
 a first driver integrated circuit, comprising a first gamma voltage generator configured to output a plurality of n first gamma voltages to n output terminals of the first gamma voltage generator, 
 a second driver integrated circuit, comprising a second gamma voltage generator configured to output a plurality of n second gamma voltages to n output terminals of the second gamma voltage generator, wherein each of the n output terminals of the first gamma voltage generator is corresponded to one of the n output terminals of the second gamma voltage generator, 
 wherein the first driver integrated circuit cascaded to the second driver integrated circuit, at least one of m output terminals among the n output terminals of the first gamma voltage generator is electrically coupled to the corresponding one of m output terminals among the n output terminals of the second gamma voltage generator to form a m common output terminal terminals, and at least one m common gamma voltage of voltages that are selected from the n first gamma voltages and the n second gamma voltages is are outputted to the m common output terminal terminals, wherein n and m are natural numbers, and n is greater than m. 
 
     
     
       2. The display driver of  claim 1 , wherein
 the first driver integrated circuit further comprises a first source driver circuit being coupled to the first gamma voltage generator, the first source driver circuit is configured to drive a display panel according to the at least one m common gamma voltage voltages, 
 the second driver integrated circuit further comprises a second source driver circuit being coupled to the second gamma voltage generator, the second source driver circuit is configured to drive the display panel according the at least one m common gamma voltage voltages. 
 
     
     
       3. The display driver of  claim 2 , wherein
 the at least one m common gamma voltage comprises voltages comprise a first common gamma voltage, 
 the first common gamma voltage is generated by either the first gamma voltage generator or the second gamma voltage generator, and 
 the first common gamma voltage is outputted to both of the first source drive driver circuit and the second source drive driver circuit. 
 
     
     
       4. The display driver of  claim 3 , wherein
 the first gamma voltage generator comprises:
 a plurality of first buffers, each of the first buffers is configured to generate one of the first gamma voltages, and 
 a first resistor string, configured to generate at least one of the first gamma voltages, and 
 
 the second gamma voltage generator comprises:
 a plurality of second buffers, each of the second buffers is configured to generate one of the second gamma voltages; and 
 a second resistor string, configured to generate at least one of the second gamma voltages. 
 
 
     
     
       5. The display driver of  claim 4 , wherein
 each of the first buffers is corresponded to one of the second buffers, 
 the first common gamma voltage is generated by either one of the first buffers or the corresponding one of the second buffers, wherein the one of the first buffers is electrically connected to the corresponding one of the second buffers. 
 
     
     
       6. The display driver of  claim 5 , wherein only one of the one of the first buffers and the corresponding one of the second buffers is turned on at a time. 
     
     
       7. The display driver of  claim 5 , wherein
 the first gamma voltage generator further comprises a first switch coupled between an output terminal of the one of the first buffers and the output terminal of the first gamma voltage generator, 
 the second gamma voltage generator further comprises a second switch coupled between an output terminal of the corresponding one of the second buffers and the output terminal of the second gamma voltage generator, and 
 only one of the first switch and the second switch is turned on at a time. 
 
     
     
       8. The display driver of  claim 4 , wherein
 each node in the first resistor string is corresponded to a node in the second resistor string, 
 the first common gamma voltage is generated by either one node of the first resistor string or the corresponding node of the second resistor string, wherein the one node of the first resistor string is electrically connected to the corresponding node of the second resistor string. 
 
     
     
       9. The display driver of  claim 4 , wherein
 the first gamma voltage generator comprises a first multiplexer connected to the m common output terminals, 
 the second gamma voltage generator comprises a second multiplexer connected to the m common output terminals,  
 each of the first gamma voltage generator and the second gamma voltage generator comprise a multiplexerthe first multiplexer and the second multiplexer are configured to select the m common gamma voltages among the n first gamma voltages and the n second gamma voltages, wherein n and m are natural numbers, and n is greater than m, and 
 each of the m common gamma voltages is generated by either the first gamma voltage generator or the second gamma voltage generator. 
 
     
     
       10. The display driver of  claim 9 , wherein
 the m output terminals of the first gamma voltage generator are selected to be coupled to the m corresponding output terminals of the second gamma voltage generator through m connection lines, the m connection lines are connected to the m common output terminals, and 
 the first buffers that are related connected to the m connection lines and the second buffers that are related connected to the m connection lines are controlled such that the a common gamma voltage among the m common gamma voltages in each of the m connection lines is generated by either an output terminal of the first gamma voltage generator or a corresponding output terminal of the second gamma voltage generator. 
 
     
     
       11. The display driver of  claim 10 , wherein
 them connection lines include a connection line that connects one of the first buffers to a corresponding one of the second buffers, and 
 either one of the first buffers or the corresponding one of the second buffers are turned on at a time to output a common gamma voltage in the connection line. 
 
     
     
       12. The display driver of  claim 10 , wherein
 the m connection lines include a connection line that connects a node of the first resistor string to a corresponding node of the second resistor string,  
 the node of the first resistor string is located between two first buffers among the first buffers, 
 the corresponding node of the second resistor string is located between two second buffers among the second buffers, the two second buffers correspond to the two first buffers, and 
 the two of the first buffers that are related to the node of the first resistor string and the and corresponding two second buffers that are related to the corresponding one of the second resistor string are controlled such that one of the two first buffers that are related to the node of the first resistor string or a corresponding one of the two second buffers that are related to the corresponding node of the second resistor string is are turned on at a time. 
 
     
     
       13. A method adapted to a display driver having a first driver integrated circuit being cascaded to and a second driver integrated circuit, the first driver integrated circuit comprising a first gamma voltage generator and the second driver integrated circuit comprising a second gamma voltage generator, the method comprising:
 selecting m output terminals among n output terminals of the first gamma voltage generator to be electrically coupled to m corresponding output terminals among n output terminals of the second gamma voltage generator to form m common output terminals; 
 generating m common gamma voltages and outputting the m common gamma voltages to the m common output terminals, wherein each of the m common gamma voltages is generated by either the first gamma voltage generator or the second gamma voltage generator; 
 providing the m common gamma voltages to the first driver integrated circuit and the second driver integrated circuit, wherein n and m are natural numbers, and n is greater than m. 
 
     
     
       14. The method of  claim 13 , wherein
 the first driver integrated circuit further comprises a first source drive driver circuit being coupled to the first gamma voltage generator, 
 the second driver integrated circuit further comprises a second source drive driver circuit being coupled to the second gamma voltage generator, and 
 the m common gamma voltages are provided to both of the first source drive driver circuit and the second source drive driver circuit. 
 
     
     
       15. A display driver, comprising:
 m common output terminals;   a first driving circuit, comprising a first gamma voltage generator coupled to the m common output terminals and configured to generate n first gamma voltages; and   a second driving circuit, comprising a second gamma voltage generator coupled to the m common output terminals and configured to generate n second gamma voltages, wherein each of the n second gamma voltages is corresponded to one of the n first gamma voltages,   wherein m common gamma voltages that are selected from the n first gamma voltages and the n second gamma voltages are outputted to the m common output terminals, wherein n and m are natural numbers, and n is greater than m, wherein   the first gamma voltage generator comprises a first multiplexer connected to the m common output terminals,   the second gamma voltage generator comprises a second multiplexer connected to the m common output terminals,   the first multiplexer and the second multiplexer are configured to select the m common gamma voltages among the n first gamma voltages and the n second gamma voltages, and   each of the m common gamma voltages is generated by either the first gamma voltage generator or the second gamma voltage generator.    
     
     
       16. The display driver of claim 15, wherein
 the first driving circuit further comprises a first source driver being coupled to the first gamma voltage generator, the first source driver is configured to drive a display panel according to the m common gamma voltages,   the second driving circuit further comprises a second source driver being coupled to the second gamma voltage generator, the second source driver is configured to drive the display panel according to the m common gamma voltages.    
     
     
       17. The display driver of claim 16, wherein
 the m common gamma voltage comprises a first common gamma voltage,   the first common gamma voltage is generated by either the first gamma voltage generator or the second gamma voltage generator, and   the first common gamma voltage is provided to both of the first source driver and the second source driver.    
     
     
       18. A display driver, comprising:
 m common output terminals; and   a plurality of gamma voltage generators, each gamma voltage generator is configured to generate a plurality of gamma voltages,   wherein each of the gamma voltage generators comprises a multiplexer being connected to the m common output terminals, the multiplexer is configured to select m common gamma voltages among the gamma voltages generated by a corresponding one of the gamma voltage generators, and the multiplexer is further configured to output the selected m common gamma voltages to the m common output terminals.    
     
     
       19. The display driver of claim 18, further comprising:
 a plurality of source drivers, each of the source drivers is coupled to a corresponding gamma voltage generator and configured to drive a display panel according to the m common gamma voltages.    
     
     
       20. The display driver of claim 19, wherein
 the m common gamma voltages are generated by either one of the gamma voltage generators, and   the m common gamma voltages are provided to all of the source drivers.    
     
     
       21. A display driver, comprising:
 a first driving circuit, comprising a first gamma voltage generator configured to output a first gamma voltage to a first output terminal,   a second driving circuit, comprising a second gamma voltage generator configured to output a second gamma voltage to a second output terminal corresponding to the first output terminal,   wherein the first output terminal and the second output terminal form a common output terminal, and a common gamma voltage of the first gamma voltage and the second gamma voltage is outputted to the common output terminal, wherein   the first gamma voltage generator comprises a first multiplexer connected to the common output terminal,   the second gamma voltage generator comprises a second multiplexer connected to the common output terminal,   the first multiplexer and the second multiplexer are configured to select the common gamma voltage among the first gamma voltage and the second gamma voltage, and   the common gamma voltage is generated by either the first gamma voltage generator or the second gamma voltage generator.    
     
     
       22. The display driver of claim 21, wherein
 the first driving circuit further comprises a first source driver being coupled to the first gamma voltage generator, the first source driver is configured to drive a display panel according to the common gamma voltage,   the second driving circuit further comprises a second source driver being coupled to the second gamma voltage generator, the second source driver is configured to drive the display panel according to the common gamma voltage.    
     
     
       23. The display driver of claim 22, wherein
 the common gamma voltage is generated by either the first gamma voltage generator or the second gamma voltage generator, and   the common gamma voltage is provided to both of the first source driver and the second source driver.    
     
     
       24. A display driver, comprising:
 a plurality of gamma voltage generators, each gamma voltage generator comprises n output terminals and is configured to output n gamma voltages to the n output terminals, wherein each of the n output terminals of one of the gamma voltage generators is respectively corresponded to one of n output terminals of each of the other gamma voltage generators,   wherein m output terminals among the output terminals of the one of the gamma voltage generators are electrically coupled to the corresponding m output terminals among the n output terminals of each of the other gamma voltage generators to form m common output terminals, and m common gamma voltages from the gamma voltage generators are outputted to the m common output terminals, wherein n and m are natural numbers, and n is greater than m, wherein   each of the gamma voltage generators comprises a multiplexer being connected to the m common output terminals, the multiplexer is configured to select the m common gamma voltages among the n gamma voltages, and   each of the m common gamma voltages is generated by one of the gamma voltage generators.    
     
     
       25. The display driver of claim 24, further comprising:
 a plurality of source drivers, each of the source drivers is coupled to a corresponding gamma voltage generator and configured to drive a display panel according to the m common gamma voltages.    
     
     
       26. The display driver of claim 25, wherein
 the m common gamma voltages comprise a first common gamma voltage,   the first common gamma voltage is generated by one of the gamma voltage generators, and   the first common gamma voltage is provided to all of the source drivers.