Summary of the invention
The objective of the invention is to defective to the prior art existence; A kind of silicon-based organic light-emitting diode micro-display driving circuit is provided; Two gordian technique points have been solved: first; The invention provides a kind of driving circuit that drives silicon-based organic light-emitting diode micro-display, the second, the present invention has utilized the functions peculiar module---the random row swept memory.Said random scanning storer is in order to accomplish fractal scanning.The control circuit of fractal scanning not within the scope of the present invention can not be referring to pertinent literature about the principle and the method for fractal scanning.
For achieving the above object, design of the present invention is:
Target of the present invention is to drive silicon-based organic light-emitting diode micro-display, and accomplishes gray-scale Control.The difference of silicon-based organic light-emitting diode micro-display and common organic light emitting diode display is; Silicon-based organic light-emitting diode micro-display is integrated in organic luminescent device on polysilicon or the monocrystalline silicon piece; Simultaneously, the organic light-emitting device driving circuit also is integrated on the same silicon chip, thereby form a volumes the tens miniscope modules that have driving circuit to the hundreds of square millimeter is only arranged usually; This miniscope module has characteristics such as low cost, low-power consumption; And the panel of common organic light emitting diode display generally several ten thousand square millimeters to hundreds of thousands square meter square millimeter, receive cost impact, can't driving circuit and display device be integrated on the same silicon chip; Common organic light emitting diode display generally is integrated on the glass substrate, relies on outside chip for driving to carry out luminous.
The present invention has designed a kind of integrated circuit, can drive the pel array of silicon-based organic light-emitting diode micro-display.As shown in Figure 1, integrated circuit of the present invention comprises organic light emitting device pixel cell array driving circuit 101, horizontal drive circuit 102, odd column driving circuit 103 and even column driving circuit 104 totally four circuit modules.Whole integrated circuit is through the fractal scan control signal of outside input; Produce drive signal through horizontal drive circuit and column drive circuit; Outputting drive voltage in the unit pixel driving circuit of light-emitting diode pixel array drives organic light emitting diode device, makes it luminous.No with traditional scan drive circuit; Horizontal drive circuit of the present invention comprises a random row swept memory 201; Control signal according to input can be visited specific scan line, realizing fractal scanning algorithm, thereby can accomplish higher scanning gray shade scale; And traditional scan drive circuit usually can only sequential scanning, the gray scale that can reach also lower.
As shown in Figure 1, pixel unit array driving circuit 101 is a driving array circuit that can drive red, green, blue three colour organic luminous diode pixels.The type of drive of this driving circuit is an active drive, and each pixel all has a storage unit, adopts static memory to realize.The gray-scale Control mode of this driving circuit adopts digital fractal scan mode; The all P raceway grooves or the mos field effect transistor of N raceway groove; All adopt the working method of digital circuit; Have only " opening " and " pass " two states, through the gray scale that the signal pulsewidth of fractal scanning algorithm generation is regulated pixel cell, fractal sweep signal is imported by external circuit.Pixel unit array driving circuit 101 has two pairs of working powers; Totally four power leads; Be respectively static memory positive supply VDD (401) and ground connection GND (402); And organic light-emitting diode pixel positive supply VOLED (403) and negative supply VCOM (404), it is in order to increase the driving voltage of Organic Light Emitting Diode that VCOM adopts negative supply.The negative electrode VCOM of all light emitting diodes links together and makes organic electroluminescence display panel form common cloudy the connection.
As shown in Figure 1, horizontal drive circuit 102, odd column driving circuit 103 and even column driving circuit 104 adopt digital circuit design method to realize.The width of considering driving pixels generally has only several microns; And the column drive circuit of each pixel need comprise circuit such as combinational logic and edge triggered flip flop; Generally placement-and-routing's resource of column drive circuit is comparatively nervous; Therefore column drive circuit is divided into odd column driving circuit 103 and even column driving circuit 104, can be arranged in respectively during the cloth domain chip about (or about) both sides.But emphasis of the present invention is the storer 201 of a random access number of scanning lines of design in horizontal drive circuit 102; This storer can be worked as row latch signal 410 effectively the time; Data on the pixel data bus are deciphered; This decoding data is the line number of next line scan-data, thus the specific scan line of random drive, in order to accomplish fractal scanning.
Scanning process to a two field picture is: at first, the pixel data serial-shift device 201 in the column drive circuit is under each pixel clock 405 effective edge and row shift signal 407 effective situation, with input of pixel data 406 serial-shifts and preservation.The data bit width of serial-shift input is relevant with display resolution, frame per second, data rate and scan mode; The present invention supports fractal scanning; More traditional lining by line scan significantly reduces required clock frequency with the input data bit width, for example, and in little display screen of 1024 row * 1280 row * 3; For realizing the target of 256 grades of gray scales, sweep frequency 100Hz; If data bit width is 48bit, then data transfer clock only needs about 50MHz, and traditional lining by line scan needs the work clock of hundreds of million Hz.After the whole serials of data line moved into, row latch signal 408 was effective, and this line data is latched in the pixel data buffer 204.Row reset signal 409 is used for the whole zero clearings of this column data.When effective one or more clock period of back of row latch signal 408 or row reset signal 409, capable latch signal 410 is effective, and pixel data 406 is the address of current random scanning row this moment, and this address is updated in the random row swept memory 201.Then, row decoding signal 411 is effective, the current effective row of scan line code translator 204 outputs.This process constantly circulates, up to a frame end.
According to above-mentioned inventive concept, the present invention adopts following technical scheme:
A kind of silicon-based organic light-emitting diode micro-display driving circuit; It is characterized in that being integrated on the same silicon with organic light emitting diode device; The all crystals pipe of its formation is all worked with the digital switch mode; " opening " and " pass " two states is only arranged, adopt the brightness and the gray scale of digital pulse width modulation system control Organic Light Emitting Diode; Said driving circuit comprises:
(1) organic light-emitting diode pixel cell array driving circuit 101 is used to produce the positive electrode voltage of organic light-emitting diode pixel unit, thereby it is luminous to drive organic LED array;
(2) horizontal drive circuit 102, are used to produce the capable gating signal of organic light-emitting diode pixel array;
(3) the odd column driving circuit 103, are used to produce the odd column gating signal of organic light-emitting diode pixel array;
(4) the even column driving circuit 104, are used to produce the even column gating signal of organic light-emitting diode pixel array;
Said organic light-emitting diode pixel cell array driving circuit 101 connects horizontal drive circuit 102, odd column driving circuit 103 and even column driving circuit 104; Pixel data 406 inserts horizontal drive circuit 102, odd column driving circuit 103 and even column driving circuit 104 respectively; Row shift signal 407, row latch signal 408 and row reset signal 409 insert odd column driving circuit 103 and even column driving circuit 104 respectively; Row latch signal 410 inserts horizontal drive circuit 102 respectively with row decoding signal 411.
The colorful array of pixels of above-mentioned pixel unit array driving circuit support is 1024 row * 1280 row; Each colour element comprises that 3 cell driving circuits are in order to drive three organic luminescent devices of adjacent red, green, blue to form full-color demonstration; Therefore cell driving circuit adds up to 3 (3 of 1024 row * 1280 row *; 932,160).Under the two voltage technologies of 350nm/; Minimum driving circuit area can reach 15um*5um; The organic light emitting diode display light-emitting area that can support can reach 14.2um*4.2um, and the silicon-based organic light-emitting diode micro-display that can support is of a size of the wide (294.91mm of the high * 19.20mm of 15.36mm
2).Each cell driving circuit is made up of 7 mosfet transistors, and wherein, 6 MOSFET form static memory cell, and 1 MOSFET is used to drive the organic light emitting diode device, and the driving voltage value of output is VDD-VCOM.Final output electrode is drawn on the chip top layer through through hole, is connected with organic luminescent device.Organic light-emitting device realizes that technology has the open scheme of more maturation, not in the scope of the invention.
Horizontal drive circuit comprises a random row swept memory and a scan line code translator.The random row swept memory is a multidigit register, is 10 in the present technique scheme, also can expand.Said scan line code translator is the code translator of 1024 outputs of one 10 inputs; It can be made up of small-scale code translator cascade, is that 1 2-4 code translator, the 2nd grade are 4 4-16 code translators as the 1st grade, and 3rd level is 64 4-16 code translators; Perhaps the 1st grade is 1 3-8 code translator; The 2nd grade is 8 4-16 code translators, and 3rd level is 128 multiple combinations such as 3-8 code translator, also can comprehensively be obtained by the RTL code through Design of Digital Circuit synthesis tool such as Design Compiler.1024 output signals of horizontal drive circuit are connected to the scan line input of pixel unit array driving circuit.
The odd column driving circuit comprises a pixel data serial-shift device and a pixel data buffer.Pixel data serial-shift device is made up of 80 groups 24 shift register concatenation, total 80*24=1920 row output data.The pixel data buffer is made up of 1920 registers, and the input of each register all corresponds to the output of respective pixel data serial shift unit, each register have Q with
QTwo outputs,
QLogic negate for Q.The output of odd column driving circuit is connected to the odd column data of pixel unit array driving circuit.
The structure of even column driving circuit and odd number driving circuit is in full accord, and just the output of even column driving circuit is connected to the even column data of pixel unit array driving circuit.Even column driving circuit and odd column driving circuit lay respectively at whole integrated circuit about (or about) both sides.
The present invention has following conspicuous substantive distinguishing features and remarkable advantage compared with prior art:
The first, the present invention has adopted the digital drive method, and transistor only is operated under " opening " and " pass " two states; Complex circuit designs degree and difficulty have been alleviated on the one hand; Can come to control more accurately and efficiently display gray scale through numerical approach on the other hand, and the conventional analogue driving circuit has utilized transistorized linear work district and operate in saturation district, most of circuit needs electric capacity; Partial circuit needs resistance; Increase circuit complexity on the one hand, cannot say for sure to demonstrate,prove the consistance of driving circuit on the other hand, therefore also cannot say for sure to demonstrate,prove the accuracy of gray-scale Control.
Second; The present invention has adopted the random row scan register, can support fractal scanning, has increased transfer efficiency; Reduced the conventional digital scan method clock frequency has been required too high requirement; The senior gray scale that can easily accomplish under the high definition resolution shows, for example, only needs the clock frequency of tens MHz just can accomplish 256 grades of gray scales demonstrations of high definition.
The 3rd, the present invention has adopted static memory mode storage pixel data, on the basis of satisfying silica-based little display area demand, more has superiority than dynamic storage, and it is low in energy consumption, speed is fast, complexity is low, high conformity.
The 4th, Design of Digital Circuit thinking of the present invention not only can be applied to Organic Light Emitting Diode, also can be applicable to the liquid crystal on silicon display technique.
The principal feature of this driving circuit is:
1, all crystals pipe is all worked with the digital switch mode, adopts the digital pulse width mode to drive organic luminescent device;
2, static memory formula pixel-driving circuit;
3, have the random row swept memory, can accomplish fractal scanning;
4, column drive circuit is divided into odd column driving circuit and even column driving circuit.
Embodiment
The preferred embodiments of the present invention accompanying drawings is following:
Embodiment one:
Referring to Fig. 1; This silicon-based organic light-emitting diode micro-display driving circuit; It is characterized in that being integrated on the same silicon with organic light emitting diode device; The all crystals pipe of its formation is all worked with the digital switch mode, and " opening " and " pass " two states is only arranged, and adopts the brightness and the gray scale of digital pulse width modulation system control Organic Light Emitting Diode; Said driving circuit comprises:
(1) organic light-emitting diode pixel cell array driving circuit 101 is used to produce the positive electrode voltage of organic light-emitting diode pixel unit, thereby it is luminous to drive organic LED array;
(2) horizontal drive circuit 102, are used to produce the capable gating signal of organic light-emitting diode pixel array;
(3) the odd column driving circuit 103, are used to produce the odd column useful signal of organic light-emitting diode pixel array;
(4) the even column driving circuit 104, are used to produce the even column useful signal of organic light-emitting diode pixel array;
Said organic light-emitting diode pixel cell array driving circuit 101 connects horizontal drive circuit 102, odd column driving circuit 103 and even column driving circuit 104; Pixel data 406 inserts horizontal drive circuit 102, odd column driving circuit 103 and even column driving circuit 104 respectively; Row shift signal 407, row latch signal 408 and row reset signal 409 insert odd column driving circuit 103 and even column driving circuit 104 respectively; Row latch signal 410 inserts horizontal drive circuit 102 respectively with row decoding signal 411.
Embodiment two:
Present embodiment and embodiment one are basic identical, and special feature is following:
Said organic light-emitting diode pixel cell array driving circuit 101; The unit pixel driving circuit of being arranged by matrix array constitutes; Said unit pixel driving circuit comprises three identical unit sub-pixel driving circuits, drives red, green, blue Organic Light Emitting Diode respectively; Said redness, green, blue cell sub-pixel driving circuit are at alternate uniform column cloth laterally or vertically; Connect horizontal drive circuit 102, odd column driving circuit 103 and even column driving circuit 104 after the parallel-series.
Said unit sub-pixel driving circuit has:
6 input pins: driving circuit power vd D; Ground connection GND; Pixel positive supply VOLED; Row useful signal row; Show and imitate signal col; Show the negative logic
of imitating signal;
1 output pin: be used to drive this sub-pixel and put pairing Organic Light Emitting Diode;
4 n channel metal oxide semiconductor field effect transistors and 2 P-channel metal-oxide-semiconductor field effect transistors constitute a static memory;
1 P-channel metal-oxide-semiconductor field effect transistor, as the driving transistors of Organic Light Emitting Diode, this transistorized source electrode is connected to the pixel positive supply, and grid is connected to the output signal of static memory, and drain electrode is connected to the positive electrode of Organic Light Emitting Diode.
Said horizontal drive circuit 102 comprises:
A random row swept memory 201, the information that is used to store next scan line is accomplished fractal scanning;
A scan line code translator 202 is used to accomplish the decoding of scan line;
Said random row swept memory 201 is connected to organic light-emitting diode pixel cell array driving circuit 101 through scan line code translator 202; Pixel data 406 inserts random row swept memory 201 with row latch signal 410, and row decoding signal 411 inserts scan line code translator 202.
Said random row swept memory 201, when row latch signal 410 effectively the time, with the part or all of data latching on the pixel data 406 in random row scanning storage 201.
Said scan line code translator 202 is N inputs, 2
NOutput N is the code translator of integer, when row decoding signal 411 effectively the time, with the output of the signal interpretation in the described random row scan register 201, forms the row gating signal.
Said odd column driving circuit 103 comprises:
An odd column pixel data serial-shift device 203 is used for the pixel data serial of odd column is moved into;
An odd column pixel data buffer 204 is used to latch the odd column pixel data of delegation;
Said odd column pixel data serial-shift device 203 is connected with OLED pixel unit array driving circuit 101 through odd column pixel data buffer 204; Said row shift signal 407 inserts odd column pixel data serial-shift device 203, and row latch signal 408 inserts odd column pixel data buffer 204 with row reset signal 409.
Said odd column pixel data serial-shift device 203; Under row shift signal 407 effective situation; On the effective edge edge of each work clock, latch the odd column data in the pixel data 406, and output odd column shifted data 416 is in odd column pixel data buffer 204.
Said odd column pixel data buffer 204, under row latch signal 408 effective situation, the odd column shifted data 416 that described odd column pixel data serial-shift device 203 is exported is transformed into odd column useful signal 415; Under row reset signal 409 effective situation, make all odd column useful signal 415 zero clearings or put 1.
Said even column driving circuit 104 comprises:
An even column pixel data serial-shift device 203 is used for the pixel data serial of even column is moved into;
An even column pixel data buffer 204 is used to latch the even column pixel data of delegation;
Said even column pixel data serial-shift device 203 is connected with OLED pixel unit array driving circuit 101 through even column pixel data buffer 204; Said row shift signal 407 inserts even column pixel data serial-shift device 203, and row latch signal 408 inserts even column pixel data buffer 204 with row reset signal 409.
Said even column pixel data serial-shift device 203; Under row shift signal 407 effective situation; On the effective edge edge of each work clock, latch the even column data in the pixel data 406, and output even column shifted data 416 is in even column pixel data buffer 204.
Said even column pixel data buffer 204, under row latch signal 408 effective situation, the even column shifted data 416 that described even column pixel data serial-shift device 203 is exported is transformed into even column useful signal 415; Under row reset signal 409 effective situation, make all even column useful signal 415 zero clearings or put 1.
Embodiment three:
As shown in Figure 1, silicon-based organic light-emitting diode micro-display driving circuit proposed by the invention mainly comprises four modules: organic light emitting device pixel cell array driving circuit 101, horizontal drive circuit 102, odd column driving circuit 103, even column driving circuit 104.Its input power supply number be organic light-emitting diode pixel power supply VOLED (401), negative electricity source VCOM (402), digital power VDD (403), digital grounding GND (404) altogether, and input signal is work clock 405, pixel data 406, row shift signal 407, row latch signal 408, row reset signal 409, capable latch signal 410, row decoding signal 411.Driving circuit is output as the pixel electrode output of organic light emitting device pixel cell array driving circuit.
As shown in Figure 2, in the present embodiment, organic light emitting device pixel cell array driving circuit 101 is cores of whole silica-based little display driver circuit, and its pairing picture element matrix array is 1024 row * 1280 * 3 row.Each pixel comprises three subpixels, is respectively red sub-pixel R, green pixel G, blue subpixels B; Therefore having 1280 * 3 on every line direction is 3840 subpixels, has 1024 subpixels on every column direction, therefore; One has 1024 * 1280 * 3=3,932,160 sub-pixel elements driving circuits; Constitute 1,310,720 colour elements.
Each organic light-emitting device sub-pixel unit is corresponding driving circuit; This driving circuit is output as a rectangular electrode; Organic Light Emitting Diode employing of the present invention cloudy mode altogether links to each other, and the negative electrode of Organic Light Emitting Diode connects together becomes a public electrode.The output voltage of pixel unit array driving circuit 101 is the driving voltage of Organic Light Emitting Diode, and the shape of pixel output electrode and area are equal to the sub-pixel unit area of Organic Light Emitting Diode, shown in the sub-pixel rectangle frame among Fig. 2.The rectangular electrode of all sub-pixels is evenly arranged in the horizontal and vertical directions side by side; Pixel separation is by the electrode minimum dimension interval determination of organic light-emitting device physics minimum dimension interval and IC design rule; Both get little, are 0.8um in the present embodiment.
As shown in Figure 3, the pixel cell driving circuit has comprised 7 MOS transistors.Wherein M1, M3, M5, M6 are nmos pass transistor, and M2, M4, M7 are the PMOS transistor.M1, M2, M3, M4, M5, M6 have constituted a static memory.M7 is the driving tube of Organic Light Emitting Diode.The pixel cell driving circuit has 6 lead-in wire inputs: VDD and GND are respectively the power lead and the ground wire of the static memory that M1-M6 constitutes; VOLED is the positive supply of pixel drive pipe M7; Row and col are respectively capable useful signal and show the effect signal;

is the logic negate signal of col; Be connected to the grid of M7, be used to control the on off state of M7.The drain electrode of M7 is the output terminal of pixel cell driving circuit, is connected to the anode of unit pixel Organic Light Emitting Diode, and the negative electrode of Organic Light Emitting Diode is connected to public electrode VCOM, but Organic Light Emitting Diode itself is not within the scope of the invention.M7 is the digital pulse width modulation system to the type of drive of Organic Light Emitting Diode, and its output has only " opening " and " pass " two kinds of situation, and M7 modulates its luminosity and gray scale through the time of lighting of control organic light emission two pipes.M1, M2, M3, M4, M5, M6 are operated under power vd D and the GND, and its withstand voltage is that VDD deducts GND.M7 is operated under power supply VOLED and the VCOM, and its withstand voltage is that VOLED deducts VCOM.The VOLED size is generally equal to VDD, and VCOM can connect negative voltage.Under the 350nm technology, VDD and VOLED are generally 3.3V, and GND meets 0V, if the withstand voltage 7V of reaching, the conduction voltage drop of M7 are 0.3V, then VCOM is minimum connects-3.7V, and the ceiling voltage that is added in Organic Light Emitting Diode can reach 6.7V.
As shown in Figure 4, horizontal drive circuit 102 comprises random row swept memory 201 and scan line code translator 204.Input signal comprises work clock 405, pixel data 406, row latch signal 410, row decoding signal 411.The output signal is row useful signal 413 (row0~row1023).The effect of horizontal drive circuit 102 is from pixel data, to take out low 10 bit data DataR0~DataR9; When row latch signal 410 effectively the time; Pixel data is latched in the random row swept memory preserves, when row decoding signal 411 effectively the time, the capable useful signal 412 after the output decoding.Horizontal drive circuit 102 is operated in the VDD/GND voltage domain.
As shown in Figure 5, random row swept memory 201 is made up of 10 d type flip flops, also can adopt other devices that have memory function to accomplish, like latch etc.When row latch signal 410 effectively the time, the random row swept memory is preserved wherein 10 bit data of pixel data 406, and this is and the distinguishing structure of traditional sweep circuit.The random row swept memory can be accepted fractal sweep signal, accomplishes fractal scanning.The random row swept memory is output as 10 row and deposits signal 413.
As shown in Figure 6, scan line code translator 204 is made up of 11 grade of 2-4 code translator, 42 grades of 4-16 code translators, 64 3 grades of 4-16 code translators, except that this scheme, also can adopt other 10~1024 decoded modes to accomplish.This code translator is by 411 controls of row decoding signal.Scan line code translator 204 is expert at decoded signal 411 effectively the time, 10 row of random row swept memory 201 outputs are deposited signal 413 decipher, and at the effective edge of work clock 405 along latching this decode results, with its maintenance.
Random row swept memory 201 can adopt the synchronous clock working method with scan line code translator 204, along work, also can adopt asynchronous system at the effective edge of work clock 405, does not need work clock;
As shown in Figure 7, odd column driving circuit 103 is identical with even column driving circuit 104 structures, all is made up of pixel data serial-shift device 203 and pixel data buffer 204, all is operated in the VDD/GND voltage domain.The function of column drive circuit is to accept the pixel data signal of serial input, and when row latch signal 408 effectively the time output show and imitate signal 415, when row reset signal 409 will be shown effect signal 415 clear 0 (or putting 1) effectively the time.
As shown in Figure 8, pixel data serial-shift device 203 is used to accomplish the serial-shift input of data.In the present embodiment, the total bit wide of pixel data is 48, and odd column driving circuit and even column driving circuit are respectively used 24, are respectively pixel data P0-P23.Each pixel data serial-shift device comprises 80 groups of d type flip flops, and every group comprises 24 d type flip flops, and odd column driving circuit and even column driving circuit comprise 80 * 24 * 2=3840 d type flip flops altogether.In each group d type flip flop, the output of each d type flip flop is connected to the input of next d type flip flop, when row shift signal 407 effectively the time, data at the effective edge of work clock 405 along carrying out serial-shift one time.Each serial data shift unit is all exported 1920 and is ranked shifted data 416 (si0~si1919).
As shown in Figure 9; Pixel data buffer 204 comprises 1920 d type flip flops, under row latch signal 408 effective situation, on the effective edge edge of work clock 405; Shifted data 416 is ranked in 1920 of pixel data serial-shift device 203 outputs to latch; Show imitate signal 415 output current lines show the effect data, comprise 1920 * 2=3840 pixel data signals of positive and negative logic, show with the pixel data of accomplishing current line.When row reset signal 409 effectively the time, show and imitate signal 415 clear 0 (or putting 1).Because the quantity of the d type flip flop in the pixel data buffer is more, so also includes the driving buffer circuit of work clock 405, row latch signal 408, row reset signal 409 in the pixel data buffer, strengthen this three input signal driving forces.