DEMULTIPLEX TYPE DISPLAY DRIVING CIRCUIT
20170345384 ยท 2017-11-30
Inventors
Cpc classification
G09G2310/0297
PHYSICS
G09G2320/0219
PHYSICS
G09G2310/0291
PHYSICS
G09G2310/0275
PHYSICS
G09G3/3607
PHYSICS
G09G2310/0289
PHYSICS
G09G2300/0452
PHYSICS
G09G3/20
PHYSICS
International classification
Abstract
The present invention provides a demultiplex type display driving circuit, including: a plurality of drive units. Each drive unit comprises three demultiplex modules, and each demultiplex module includes two switch elements. The first switch element and the second switch element are controlled to be alternately on with the first branch control signal and the second branch control signal. The third branch control signal controls the two switch elements of the second and the third demultiplex modules to be alternately on to sequentially input the data signal to the first, the second, the third and the fourth data lines. Thus, division one to four of the data signal can be achieved with the three branch control signals. In comparison with prior art, the amount of the branch control signals is decreased, and meanwhile, the CMOS transmission gate is employed to be the switch element in the demultiplex modules.
Claims
1. A demultiplex type display driving circuit, comprising: a plurality of drive units, wherein each drive unit comprises: a first demultiplex module (10), a second demultiplex module (20), a third demultiplex module (30), first, second, third and fourth data lines (D1, D2, D3, D4) which are mutually parallel, sequentially aligned and vertical, and sub pixels (40) of multiple rows, four columns, which are aligned in array; the sub pixel (40) is electrically coupled to a data line corresponded with the column where the sub pixel (40) is; the first demultiplex module (10) comprises: a first switch element (11) and a second switch element (12), and the second demultiplex module (20) comprises: a third switch element (21) and a fourth switch element, (22), and third demultiplex module (30) comprises: a fifth switch element (31) and a sixth switch element (32); all the first, the second, the third, the fourth, the fifth and the sixth switch elements (11, 12, 21, 22, 31, 32) comprise: a control end, an input end and an output end; the control end of the first switch element (11) is electrically coupled to a first branch control signal (Demux1), and the input end is electrically coupled to a data signal (Input), and the output end is electrically coupled to the input end of the third switch element (21) and the input end of the fourth switch element (22); the control end of the second switch element (12) is electrically coupled to a second branch control signal (Demux2), and the input end is electrically coupled to the data signal (Input), and the output end is electrically coupled to the input end of the fifth switch element (31) and the input end of the sixth switch element (32); the control end of the third switch element (21) is electrically coupled to a third branch control signal (Demux3), and the output end is electrically coupled to a first data line (D1); the control end of the fourth switch element (22) is electrically coupled to a third branch control signal (Demux3), and the output end is electrically coupled to a second data line (D2); the control end of the fifth switch element (31) is electrically coupled to a third branch control signal (Demux3), and the output end is electrically coupled to a third data line (D3); the control end of the sixth switch element (32) is electrically coupled to a third branch control signal (Demux3), and the output end is electrically coupled to a fourth data line (D4); pulse durations of the first branch control signal (Demux1) and the second branch control signal (Demux2) are the same, and a pulse duration of the third branch control signal (Demux3) is a half of the pulse duration of the first branch control signal (Demux1), and the first switch element (11) and the second switch element (12) are alternately on, and the third switch element (21) and the fourth switch element (22) are alternately on, and the fifth switch element (31) and the sixth switch element (32) are alternately on to sequentially input the data signals (Input) to the first, the second, the third and the fourth data lines (D1, D2, D3, D4).
2. The demultiplex type display driving circuit according to claim 1, further comprising: a first inverter (51) and a second inverter (52); an input end of the first inverter (51) receives the third branch control signal (Demux3), and an output end of the first inverter (51) is electrically coupled to an output end of the second inverter (52); an input end of the second inverter (52) is coupled to the third branch control signal (Demux3); all the third switch element (21), the fourth switch element (22), the fifth switch element (31) and the sixth switch element (32) are CMOS transmission gates; the input ends and the output ends of the third switch element (21), the fourth switch element (22), the fifth switch element (31) and the sixth switch element (32) respectively correspond to an input end and an output end of the CMOS transmission gate; the control ends of the third switch element (21), the fourth switch element (22), the fifth switch element (31) and the sixth switch element (32) comprise: a high voltage level control and a low voltage level control end of the CMOS transmission gate; the high voltage level control end of the third switch element (21) is electrically coupled to the third branch control signal (Demux3), and the low voltage level control end is electrically coupled to the output end of the first inverter (52); the high voltage level control end of the fourth switch element (22) is electrically coupled to the output end of the first inverter (52), and the low voltage level control end is electrically coupled to the third branch control signal (Demux3); the high voltage level control end of the fifth switch element (31) is electrically coupled to the third branch control signal (Demux3), and the low voltage level control end is electrically coupled to the output end of the first inverter (51); the high voltage level control end of the sixth switch element (32) is electrically coupled to the output end of the first inverter (51), and the low voltage level control end is electrically coupled to the third branch control signal (Demux3).
3. The demultiplex type display driving circuit according to claim 1, wherein both the first switch element (11) and the second switch element (12) are N type TFTs, and the control ends, the input ends and the output ends of the first switch element (11) and the second switch element (12) respectively correspond to a gate, a source and a drain of the N type TFT.
4. The demultiplex type display driving circuit according to claim 1, further comprising: a third inverter (53), a fourth inverter (54), a fifth inverter (55) and a sixth inverter (56); the input end of the third inverter (53) receives the first branch control signal (Demux1), and an output end of the third inverter (53) is electrically coupled to an output end of the sixth inverter (56); an input end of the fourth inverter (54) receives the second branch control signal (Demux2), and an output end of the fourth inverter (54) is electrically coupled to an output end of the fifth inverter (55); an input end of the fifth inverter (55) receives the second branch control signal (Demux2); an input end of the sixth inverter (56) receives the first branch control signal (Demux1); both the first switch element (11) and the second switch element (12) are CMOS transmission gates; the input ends and the output ends of the first switch element (11) and the second switch element (12) respectively correspond to an input end and an output end of the CMOS transmission gate; the control ends of the first switch element (11) and the second switch element (12) comprise: a high voltage level control and a low voltage level control end of the CMOS transmission gate; the high voltage level control of the first switch element (11) is electrically coupled to the first branch control signal (Demux1), and the low voltage level control end is electrically coupled to the output end of the third inverter (53); the high voltage level control of the second switch element (12) is electrically coupled to the second branch control signal (Demux2), and the low voltage level control end is electrically coupled to the output end of the fourth inverter (54).
5. The demultiplex type display driving circuit according to claim 3, wherein the first branch control signal (Demux1) and the second branch control signal (Demux2) are inverse in phase.
6. The demultiplex type display driving circuit according to claim 1, wherein both the third switch element (21) and the fifth element (31) are N type TFTs, and both the fourth switch element (22) and the sixth switch element (32) are P type TFT; the control ends, the input ends and the output ends of the third switch element (21) and the fifth switch element (31) respectively correspond to a gate, a source and a drain of the N type TFT; the control ends, the input ends and the output ends of the fourth switch element (22) and the sixth switch element (32) respectively correspond to a gate, a source and a drain of the P type TFT.
7. The demultiplex type display driving circuit according to claim 1, wherein the sub pixels (40) of multiple rows, four columns in each drive unit respectively are: red sub pixels (R) of one column, green sub pixels (G) of one column, blue sub pixels (B) of one column and white sub pixels (W) of one column, which are sequentially aligned.
8. The demultiplex type display driving circuit according to claim 7, wherein the first branch control signal (Demux1), the second branch control signal (Demux2) and the third branch control signal (Demux3) are combined with one another to sequentially input the data signal (Input) to the first, the second, the third and the fourth data lines (D1, D2, D3, D4) to respectively charge the red sub pixel (R), the green sub pixel (G), the blue sub pixel (B) and the white sub pixel (W).
9. The demultiplex type display driving circuit according to claim 8, wherein as charging the red sub pixel, the first switch element (11), the third switch element (21) and the fifth switch element (31) are on, and the second switch element (12), the fourth switch element (22) and the sixth switch element (32) are off; as charging the green sub pixel, the first switch element (11), the fourth switch element (22) and the sixth switch element (32) are on, and the second switch element (12), the third switch element (21) and the fifth switch element (31) are off; as charging the blue sub pixel, the second switch element (12), the third switch element (21) and the fifth switch element (31) are on, and the first switch element (11), the fourth switch element (22) and the sixth switch element (32) are off; as charging the white sub pixel, the second switch element (12), the fourth switch element (22) and the sixth switch element (32) are on, and the first switch element (11), the third switch element (21) and the fifth switch element (31) are off.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] In order to better understand the characteristics and technical aspect of the invention, please refer to the following detailed description of the present invention is concerned with the diagrams, however, provide reference to the accompanying drawings and description only and is not intended to be limiting of the invention.
[0047] In drawings,
[0048]
[0049]
[0050]
[0051]
[0052]
[0053]
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0054] For better explaining the technical solution and the effect of the present invention, the present invention will be further described in detail with the accompanying drawings and the specific embodiments.
[0055] Please refer from
[0056] the sub pixel 40 is electrically coupled to a data line corresponded with the column where the sub pixel 40 is, and besides, a scan line is further located corresponding to the sub pixels of each row, and a switch TFT is located corresponding to each sub pixel, and a gate of the switch TFT is electrically coupled to the scan line corresponded with the row where the sub pixel 40 is, and a source is electrically coupled to the data line corresponded with the column where the sub pixel 40 is, and a drain is electrically coupled to the pixel electrode in the sub pixel 40.
[0057] the first demultiplex module 10 comprises: a first switch element 11 and a second switch element 12, and the second demultiplex module 20 comprises: a third switch element 21 and a fourth switch element, 22, and third demultiplex module 30 comprises: a fifth switch element 31 and a sixth switch element 32; all the first, the second, the third, the fourth, the fifth and the sixth switch elements 11, 12, 21, 22, 31, 32 comprise: a control end, an input end and an output end; the control end of the first switch element 11 is electrically coupled to a first branch control signal Demux1, and the input end is electrically coupled to a data signal Input, and the output end is electrically coupled to the input end of the third switch element 21 and the input end of the fourth switch element 22; the control end of the second switch element 12 is electrically coupled to a second branch control signal Demux2, and the input end is electrically coupled to the data signal Input, and the output end is electrically coupled to the input end of the fifth switch element 31 and the input end of the sixth switch element 32; the control end of the third switch element 21 is electrically coupled to a third branch control signal Demux3, and the output end is electrically coupled to a first data line D1; the control end of the fourth switch element 22 is electrically coupled to a third branch control signal Demux3, and the output end is electrically coupled to a second data line D2; the control end of the fifth switch element 31 is electrically coupled to a third branch control signal Demux3, and the output end is electrically coupled to a third data line D3; the control end of the sixth switch element 32 is electrically coupled to a third branch control signal Demux3, and the output end is electrically coupled to a fourth data line D4.
[0058] Specifically, pulse durations of the first branch control signal Demux1 and the second branch control signal Demux2 are the same, and a pulse duration of the third branch control signal Demux3 is a half of the pulse duration of the first branch control signal Demux1, and the first switch element 11 and the second switch element 12 are alternately on, and the third switch element 21 and the fourth switch element 22 are alternately on, and the fifth switch element 31 and the sixth switch element 32 are alternately on to sequentially input the data signals Input to the first, the second, the third and the fourth data lines D1, D2, D3, D4, and thus division one to four of the data signal Input can be achieved with the three branch control signals to effectively decrease the amount of the branch control signals and to reduce the loading of the control signal IC.
[0059] Specifically, the sub pixels 40 of multiple rows, four columns in each drive unit respectively are: red sub pixels R of one column, green sub pixels G of one column, blue sub pixels B of one column and white sub pixels W of one column, which are sequentially aligned. The first branch control signal Demux1, the second branch control signal Demux2 and the third branch control signal Demux3 are combined with one another to sequentially input the data signal Input to the first, the second, the third and the fourth data lines D1, D2, D3, D4 to respectively charge the red sub pixel R, the green sub pixel G, the blue sub pixel B and the white sub pixel W.
[0060] Specifically, the first, the second, the third, the fourth, the fifth and the sixth switch elements 11, 12, 21, 22, 31, 32 can use the corresponding switch element, such as N type TFT, P type TFT, CMOS transmission gate according to the design requirement.
[0061] Please refer to
[0062] All the third switch element 21, the fourth switch element 22, the fifth switch element 31 and the sixth switch element 32 are CMOS transmission gates. Then, for achieving the normal work of the CMOS transmission gates, the circuit further comprises a first inverter 51 and a second inverter 52, wherein an input end of the first inverter 51 receives the third branch control signal Demux3, and an output end of the first inverter 51 is electrically coupled to an output end of the second inverter 52; an input end of the second inverter 52 is coupled to the third branch control signal Demux3.
[0063] Correspondingly, the input ends and the output ends of the third switch element 21, the fourth switch element 22, the fifth switch element 31 and the sixth switch element 32 respectively correspond to an input end and an output end of the CMOS transmission gate, and the control ends of the third switch element 21, the fourth switch element 22, the fifth switch element 31 and the sixth switch element 32 comprise: a high voltage level control and a low voltage level control end of the CMOS transmission gate. Namely, the high voltage level control end of the third switch element 21 is electrically coupled to the third branch control signal Demux3, and the low voltage level control end is electrically coupled to the output end of the first inverter 52, and an input end is electrically coupled to the drain of the first switch element 11, and an output end is electrically coupled to the first data line D1; the high voltage level control end of the fourth switch element 22 is electrically coupled to the output end of the first inverter 52, and the low voltage level control end is electrically coupled to the third branch control signal Demux3, and an input end is electrically coupled to the drain of the first switch element 11, and an output end is electrically coupled to the second data line D2; the high voltage level control end of the fifth switch element 31 is electrically coupled to the third branch control signal Demux3, and the low voltage level control end is electrically coupled to the output end of the first inverter 51, and an input end is electrically coupled to the drain of the first switch element 12, and an output end is electrically coupled to the third data line D3; the high voltage level control end of the sixth switch element 32 is electrically coupled to the output end of the first inverter 51, and the low voltage level control end is electrically coupled to the third branch control signal Demux3, and an input is electrically coupled to the drain of the second switch element 12, and an output end is electrically coupled to the fourth data line D4.
[0064] Please refer to
[0065] Please refer to
[0066] Specifically, in the present invention, the first branch control signal Demux1, the second branch control signal Demux2 and the third branch control signal Demux3 are combined with one another to sequentially input the data signal Input to the first, the second, the third and the fourth data lines D1, D2, D3, D4 to respectively charge the red sub pixel R, the green sub pixel G, the blue sub pixel B and the white sub pixel W. As charging the red sub pixel, the first switch element 11, the third switch element 21 and the fifth switch element 31 are on, and the second switch element 12, the fourth switch element 22 and the sixth switch element 32 are off; as charging the green sub pixel, the first switch element 11, the fourth switch element 22 and the sixth switch element 32 are on, and the second switch element 12, the third switch element 21 and the fifth switch element 31 are off; as charging the blue sub pixel, the second switch element 12, the third switch element 21 and the fifth switch element 31 are on, and the first switch element 11, the fourth switch element 22 and the sixth switch element 32 are off; as charging the white sub pixel, the second switch element 12, the fourth switch element 22 and the sixth switch element 32 are on, and the first switch element 11, the third switch element 21 and the fifth switch element 31 are off.
[0067] Specifically, referring to
[0068] As charging the green sub pixel G, the data signal Input is inputted to the sources of the first switch element 11 and the second switch element 12, and the first branch control signal Demux1 is high voltage level to make the first switch element 11 be on, and the second branch control signal Demux2 is low voltage level to make the second switch element 12 be off. The data signal Input is inputted to the input ends of the third switch element 21 and the fourth switch element 22 through the first switch element 12, and the third branch control signal Demux3 is low voltage level, which becomes high voltage level after the function of the first inverter 51 and the second inverter 52 to make the high voltage level control end of the third switch element 21 appear to be low voltage level, and to make the low voltage control end appear to be high voltage level, and to make the high voltage level control end of the fourth switch element 22 appear to be high voltage level, and to make the low voltage control end appear to be low voltage level. Thus, the third switch element 21 is off and the fourth switch element 22 is on, and the data signal Input is inputted to the second data line D2 through the fourth switch element 22 for charging the green sub pixel G.
[0069] As charging the blue sub pixel B, the data signal Input is inputted to the sources of the first switch element 11 and the second switch element 12, and the first branch control signal Demux1 is low voltage level to make the first switch element 11 be off, and the second branch control signal Demux2 is high voltage level to make the second switch element 12 be on. The data signal Input is inputted to the input ends of the fifth switch element 31 and the sixth switch element 32 through the second switch element 12, and the third branch control signal Demux3 is high voltage level, which becomes low voltage level after the function of the first inverter 51 and the second inverter 52 to make the high voltage level control end of the fifth switch element 31 appear to be high voltage level, and to make the low voltage control end appear to be low voltage level, and to make the high voltage level control end of the sixth switch element 32 appear to be low voltage level, and to make the low voltage control end appear to be high voltage level. Thus, the fifth switch element 31 is on and the sixth switch element 32 is off, and the data signal Input is inputted to the third data line D3 through the fifth switch element 31 for charging the blue sub pixel B.
[0070] As charging the white sub pixel W, the data signal Input is inputted to the sources of the first switch element 11 and the second switch element 12, and the first branch control signal Demux1 is low voltage level to make the first switch element 11 be off, and the second branch control signal Demux2 is high voltage level to make the second switch element 12 be on. The data signal Input is inputted to the input ends of the fifth switch element 31 and the sixth switch element 32 through the second switch element 12, and the third branch control signal Demux3 is low voltage level, which becomes high voltage level after the function of the first inverter 51 and the second inverter 52 to make the high voltage level control end of the fifth switch element 31 appear to be low voltage level, and to make the low voltage control end appear to be high voltage level, and to make the high voltage level control end of the sixth switch element 32 appear to be high voltage level, and to make the low voltage control end appear to be low voltage level. Thus, the fifth switch element 31 is off and the sixth switch element 32 is on, and the data signal Input is inputted to the fourth data line D4 through the sixth switch element 32 for charging the white sub pixel W.
[0071] The working procedures of the second and the third embodiment are similar as the first embodiment. As charging the red sub pixel R, the first branch control signal Demux1, the second branch control signal Demux2 and the third branch control signal Demux3 are controlled to make the data signal Input charge the red sub pixel R through the first switch element 11 and the third switch element 21; as charging the green sub pixel G, the first branch control signal Demux1, the second branch control signal Demux2 and the third branch control signal Demux3 are controlled to make the data signal Input charge the green sub pixel G through the first switch element 11 and the fourth switch element 22; as charging the blue sub pixel B, the first branch control signal Demux1, the second branch control signal Demux2 and the third branch control signal Demux3 are controlled to make the data signal Input charge the blue sub pixel B through the second switch element 12 and the fifth switch element 31; as charging the white sub pixel W, the first branch control signal Demux1, the second branch control signal Demux2 and the third branch control signal Demux3 are controlled to make the data signal Input charge the white sub pixel W through the second switch element 12 and the sixth switch element 32, and the repeated description is omitted here.
[0072] In the first, the second and the third embodiments, with the circuit design, only three branch control signals are utilized to achieve one to four division of the data signal Input. In comparison with prior art, the amount of the branch control signals is decreased and the loading of the control signal IC is reduced, and meanwhile, the CMOS transmission gate is employed to be the switch element. It can effectively reduce the equivalent conduction resistance of the demultiplex module, and reduce the loading of the control signal IC to stable the output signal and to eliminate the feed through effect of the pixel.
[0073] In conclusion, the present invention provides a demultiplex type display driving circuit, including: a plurality of drive units. Each drive unit comprises three demultiplex modules, and each demultiplex module includes two switch elements. The first switch element and the second switch element are controlled to be alternately on with the first branch control signal and the second branch control signal. The third branch control signal controls the two switch elements of the second and the third demultiplex modules to be alternately on to sequentially input the data signal to the first, the second, the third and the fourth data lines for respectively discharging the red, the green, the blue and the white sub pixels. Thus, one to four division of the data signal can be achieved with the three branch control signals. In comparison with prior art, under the premise of achieving the one to four division of the data signal, the amount of the branch control signals is decreased, and meanwhile, the CMOS transmission gate is employed to be the switch element in the demultiplex modules. It can effectively reduce the equivalent conduction resistance of the demultiplex module, and reduce the loading of the control signal IC to stable the output signal and to eliminate the feed through effect of the pixel.
[0074] Above are only specific embodiments of the present invention, the scope of the present invention is not limited to this, and to any persons who are skilled in the art, change or replacement which is easily derived should be covered by the protected scope of the invention. Thus, the protected scope of the invention should go by the subject claims.