CN1421028A - Method and apparatus for driving digital display by distributing PWM pulses over time - Google Patents
Method and apparatus for driving digital display by distributing PWM pulses over time Download PDFInfo
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- CN1421028A CN1421028A CN01807359A CN01807359A CN1421028A CN 1421028 A CN1421028 A CN 1421028A CN 01807359 A CN01807359 A CN 01807359A CN 01807359 A CN01807359 A CN 01807359A CN 1421028 A CN1421028 A CN 1421028A
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/2007—Display of intermediate tones
- G09G3/2018—Display of intermediate tones by time modulation using two or more time intervals
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/04—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions
- G09G3/06—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions using controlled light sources
- G09G3/12—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions using controlled light sources using electroluminescent elements
- G09G3/14—Semiconductor devices, e.g. diodes
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2320/00—Control of display operating conditions
- G09G2320/02—Improving the quality of display appearance
- G09G2320/0261—Improving the quality of display appearance in the context of movement of objects on the screen or movement of the observer relative to the screen
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- Computer Hardware Design (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
- Liquid Crystal Display Device Control (AREA)
- Control Of El Displays (AREA)
- Transforming Electric Information Into Light Information (AREA)
- Liquid Crystal (AREA)
Abstract
When applied to a digital display, the invention provides a signal representing the digital data comprising a plurality of smaller pulses distributed over the refresh time period to drive the display element. A logic circuit is provided to generate a plurality of combinable signals so that the incoming data can be combined with the signals to determine the mix of signals generated as a final output. The individual signals are generated by identifying the lowest order active bit of a counter that is subdividing the appropriate time period into smaller time divisions and generating a pulse on one of a plurality of outputs with each unique lowest order bit identified output on a separate output and successive common lowest order bits identified generating pulses on the same output.
Description
Technical field
The invention relates to the method and apparatus that drives digital indicator by the width-modulation pulse that distributes in time.Particularly, though be not only to have, this method and apparatus can be implemented in the field such as the digital indicator screen of LED or LCD screen or projector, plasm TV or other display device screens that use numerical informations.
Background technology
Recently, the digital indicator screen has become main.These screens have various ways, though and the present invention generally will describe with reference to the LED screen, think that easily identical consideration can be applicable to other digital indicator systems.
Lifting a LED screen is example, and it generally can be provided by the screen that comprises a plurality of pixels.Each pixel can comprise a plurality of different color LED elements, and the Color Range of hope is provided.And, can comprise redness, blueness and green LED element on usually.
During one sets, on pixel, provide specific color, can provide Color Range by varying strength being provided respectively to the illumination of red, green and blue element.
Along with the use of digital indicator, the variation on the intensity of each LED element is generally recently reached by the relative time percentage that each element is energized.
This digital indicator can be operated under multiple renewal frequency.Typical frequencies is about 60Hz, and continuous relatively clear signal is provided to human eye.At 60Hz frequency place, each pixel need show wishes color, and in during 1/60 second suitable energy level is provided to each LED element.
When data are provided to LED and LED substantially in transient operation with digital form, only the suitable part of this reproducting periods is come the illumination LED element, and provide energy level variations in the reproducting periods, utilize digital indicator, generally not by in time durations, providing higher or than low-lying level, but, need in this period, provide the relevant number percent of average color intensity, thereby operation related elements by providing one group of power level to come only in the number percent of reproducting periods, to come illumination component.Often have with the electric current that is applied to element and change corresponding nonlinear response.Therefore, the general time quantum of more wishing to change the element excited target, but not change the immediate current of being supplied, and it maintain whole during in.
Suppose that reproducting periods serves as reasons time of " T " expression, by as required the suitable element illumination of the suitable part of " T " being provided the varying strength rank of each color.
Perhaps the straightforward procedure of implementing this function be during " T " begin to locate switching device, and before element is closed during suitable part encourage this element.For example, if wish that color has the redness of 50% intensity, then in preceding half time durations " T " underexcitation red element.By from during begin promptly to change time durations " T " this part varying strength is provided.
When this system is utilized, produce certain visual effects.This visual effect is called as " flash of light ".
Though the mechanism of this visual effect is all understood as yet, it is believed that this effect is because of energy uneven distribution and producing in time durations " T ".
As pointing out in the precedent, only in preceding half time durations " T ", provide 50% intensity to come exciting element.If image is static, then " T " similarly encouraged during the follow-up time, and is evenly distributed and do not produce special visual distortion.Yet, moving image as if one and be projected on the screen, the borderline pixel of this mobile image need obviously change intensity continuously between the update cycle.
If consider that an element is energized 50% during one-period, and in following one-period, be energized 25%, then in to preceding half first reproducting periods and preceding 1/4th next reproducting periods, the simple execution of element provides correct average energy to each reproducting periods.Yet the beginning of reproducting periods and end and observer's thought is asynchronous.If consider a little during the long period, for example, " T " adds 25% during the starting point start time in first cycle in two cycles, then both's generation in one 1.25 " T " time durations during 50% " T " and 25% " T " excitation.Producing average energy in causing during 60% 1.25 " T " distributes.Significantly, the intensity between this extended period in addition than the very first time during the intensity of " T " stronger, the intensity of " T " also is eager to excel during the follow-up time of reduction.
The visual effect of flash of light produces the bright or concealed wire of trailing the mobile image that crosses screen.
On general, adopt two methods to attempt and overcome this effect.
First method is to reduce the update cycle significantly.Though do not stop effect to take place at this, obviously the update cycle can reduce human eye effect clearly faster.General this effect that goes up moves faster and becomes clear on the image crossing display.The difficulty of this proposal is that reducing in the update cycle obviously increases the required processing procedure of display, thereby and makes the hardware complexity that relates to increase cost.Most economical reproducting periods is only fast slightly than the detection rates of human eye.
Described system uses width modulation " PWM " signal that desirable strength is provided.As previously mentioned, simple form is only the number percent of " T " during the length of single pulse and the desired time to be complementary.
Owing to increase the cost difficulty of update cycle and still will solve the flash of light problem, utilized additive method the pulse Len req in the time durations " T " to be processed into a series of pulses that are distributed in this time durations.The average pulse that spreads all over time durations " T " distributes and has overcome this problem.
A straightforward procedure of implementing this function is that time durations " T " is divided into a series of discrete time intervals.These time intervals can be expressed as represent 50% during " T " during " T " square, represent 25% during second square of " T ", represent another square of " T " during 12.5% or the like.
During being distributed in discretely, these time intervals in " T " time,, then can utilize 50% and 12.5% discrete time interval that this value is provided if be desirable to provide 5/8 intensity of available full strength.If in whole time durations " T ", 50% and 12.5% the discrete time district be non-conterminous time interval, then take place on average.Usually, 50% time interval can be adjacent with an end points of time durations " T ", and 25% is interval 50% interval adjacent with this, and 12.5% is interval and 25% interval adjacent and away from 50% interval or the like.5/8 or 62.5% intensity provides two square times, and for example the display device of LED element is illuminated during this period, and is separated by 25% unexcited time interval of element.
Interval number according to time durations " T " is subdivided into can provide more complicated configuration.
Yet as if one in the approaching discrete time durations border of the intensity of pixel, this kind of system still has any problem.For example, if intensity will be 50%, then still provide intensity by single pulse at an end points place of time durations " T ".Similarly, will be just over the number percent of this intensity 50% value and represent in a smaller again pulse of time interval " T " other end usually by single 50% pulse.This not too influences during All Time in " T " average pulse during near those special time square borders at intensity level.
For better solution is provided, nearest product has had the memory body of Eprom form.Eprom comprises that question blank is to provide required average signal.
The exemplary device of this enforcement is shown among Fig. 1.In order to illustrate, the indivedual lines in Eprom memory body typical case memory body position 128 and 64 partly are provided among Fig. 2.
Please refer to Fig. 1, the simplification that device is shown partly drives single LED element 1.
On general, vision signal or similar signal can be received with analog form by total system, and convert digital format to.Have in a pixel in the situation of display of redness, blueness and green individual elements, data are expressed as the digital number of the strength grade of representing this specific LED in during this renewal cycling time.
As simplifying at this in form to explanation demonstrates, data can be provided as the digital signal 2 of 8 binary digit forms.Bits number in the binary digit signal only depends on the gradient number of each component strength.8 signals provide LED element 1 to represent 256 discrete binary digits of 256 independent strength grades in time durations " T ".This can change as required and it should be noted that when being provided to the pixelation screen with red, blue and green assembly, the last color of pixel is decided by the blending ratio of each in these three elements at least.Therefore, 256 gradients of each color provide the Color Range of the integral body that surpasses 16.7 hundred ten thousand last pixel in three colors.
As in this known technology example, showing that data-signal is provided to Eprom 3.On the typical case, Eprom 3 will keep at least 256 discrete memory body positions, and each position is at sending into the possible strength grade that data are wished.
What be connected with Eprom is counter 4, and it is used as 8 digit counters of coupling in this known technology embodiment.Clock 5 actuation counter 4.Then explain orally as in describing, the bits number of counter need not the number of matched data position, and then can increase if desired.Bits number unlikely reduces.Because this will reduce some the discrete degree to the LED1 usable intensity.
In the single memory body position in Eprom, the memory body position can similarly comprise a sequence bit, and the number of the discrete value that the length of sequence is produced by counter 4 decides.In this specific examples that shows in Fig. 1, each the memory body position in Eprom can comprise a string 256 independent positions.
In order to explain the operation of this known technology embodiment, can be with reference to figure 2, wherein demonstrate a part of memory body position of the memory body position of representing 128 or 64 data input.These are that the canonical dissection of memory body position helps illustrate this prior art.
If data 2 wish the time of driving LED be 50% during, then data 2 can be provided as and 256 of 8 bit representations 128 binary bit numbers that equate in may the binary bit numbers.As preceding 16 in 128 some 256 positions that demonstrate in the memory body position 128 of the memory body position that shows among Fig. 2.
When counter 4 comes circulation time by in 256 discrete numbers that driven by clock 5 each, in 128 memory body positions one continuously the position be considered.As showing in 16 before this, second of each in 128 address comprises that one " 1 " come illumination LED 1.
The result is that the output 6 of Eprom 3 comprises 128 individual pulses, and its sum reaches 50% of whole time durations " T ".
Please refer in Eprom 3 memory body position with the data 2 of the binary form representative of numeral 64, see for preceding 16 that can from Fig. 2, show, each the 4th comprises one " 1 ", makes output 6 comprise the pulse of 64 discrete distributions that add up to 25% pot life " T ".
As in this known technology, showing, Eprom at each discrete send into data-signal successfully pulse is distributed in the time " T " during in.
In fact, this Eprom can produce signal at a plurality of independent LED elements.Therefore, need not to provide separately Eprom to each LED element.Can be by the actual number of the LED element 1 of each Eprom 3 addressing, not only can be by the simple speed decision that surpasses Eprom 3, can also decide by the ability that a communication path is provided to also with the LED element 1 of abundant speed operation.
With present skill level, still need to be provided with any true paragraph that a plurality of Eprom come the driving display screen.Typical known technology system can utilize 6 Eprom on the drive plate of 512 pixel portions sections that respectively comprise 3 LED elements.
Though this known technology has overcome the problem of flash of light, use Eprom and be connected to the driving circuit of LED very expensive.Though the number of required Eprom can be by comprising that multiplexer or other technologies make Eprom carry out addressing to more LED and reduce, these multiplexers also increase whole cost.
Goal of the invention
The purpose of this invention is to provide a kind of by drive the method and apparatus of digital indicator at whole section time distributing PWM signal, this method and apparatus can overcome some shortcomings of known technology by some average pulses are provided in whole period, reduce the needs as expensive objects such as Eprom simultaneously.
Brief summary of the invention
In view of the above, in first aspect, the present invention can extensively be called and comprise and a kind ofly drive the method for digital indicator by distribution pulse-width signal in whole period that this method comprises the following steps:
In time durations " T ", produce a plurality of pulse signals;
Each of described a plurality of pulse signals provides at least one individual pulses in this time durations " T ";
During in the discrete time interval in " T ", with respect to any other pulse in any signal in described a plurality of pulse signals, produce each pulse of described a plurality of pulse signals; And
Make up described pulse signal according to data, comprise the output signal of the pulse of distribution with generation, the pulse summation representative of described distribution is by " T " during the part-time of sending into data predicting.
In view of the above, in second aspect, the present invention can extensively be called and comprises a kind ofly at the device that drives digital indicator by distribution pulse-width signal in the whole period " T ", and this device comprises:
At least one signal generator produces a plurality of pulse signals, wherein, each described signal comprises the distribution of individual pulses, and, relative with the individual pulses of all pulse signals whole during in the discrete time interval in " T ", each described individual pulses is provided;
On behalf of this, the AND coupling arrangement the position of sending into data-signal and described a plurality of pulse signals combination, thereby send into data-signal so which to select in the described pulse signal should be combined; And
The OR coupling arrangement is combined into the distribution pulse of representing this single series of sending into data to described selected signal in time durations " T ".
In view of the above, in the third aspect, the present invention can extensively be called and comprises a kind ofly by producing the discrete pulse signal of a plurality of times that the is fit to subsequent combination method of display that driven number, and this method comprises the following steps:
Produce the continuous binary bit number of wishing the time durations segmentation;
The inferior sequence number of exporting of the level of the continuous binary digit purpose least significant bit (LSB) that identification is produced, the corresponding single time interval of each number, identification lowermost level time position; And
Produce an output pulse on one in a plurality of outputs capable of being combined, and contain the other one by one pulse that produces at the time interval of each segmentation and by the common lowermost level that in a common output, the produces time position pulse that recognizer produced.
In view of the above, in fourth aspect, the present invention can extensively be called and comprises a kind ofly by produce the device that a plurality of pulse signals capable of being combined drive digital indicator in whole period, and this device comprises:
Counter, the binary bit number that produces a sequence segments time durations;
Lowermost level time position recognizer, the least significant bit (LSB) of identification from the binary bit sequence of this counter output, and export a continuous signal of representing this least significant bit (LSB), such signal is corresponding with each described timing separation; And
Pulse generator activates each the independent lowermost level time pulse of position in a discrete output of being discerned, and activates the continuous impulse of the common lowermost level time position that will be created in the common output.
Description of drawings
Referring now to following accompanying drawing preferred embodiment of the present invention is described, wherein:
Fig. 1 demonstration is used to provide the prior art devices that is distributed in the pulse-width signal in whole period;
Fig. 2 demonstration is represented the memory body address according to the part of Eprom in the device shown in Figure 1;
Fig. 3 shows the synoptic diagram of preferred embodiment of the present invention;
Fig. 4 shows a plurality of pulse signals according to simplified embodiment of the present invention; And
Fig. 5 simplifies a kind of sketch plan that may export of form for expression the present invention.
Embodiment
The invention relates to a kind of method and apparatus that drives digital indicator by distribution width-modulation pulse in whole period.
In preferred versions, embodiment implements with the form of the display device screen of display digit data-signal 2.In order to describe purpose, display device screen can be represented by single LED element 1.Certainly in practicality, the present invention implements by a plurality of this LED element 1 that control is formed in the individual pixel.
Moreover, the invention is not restricted to as such as the LED element of plasm TV, LCD projector, LCD screen and the numerical data of other display systems such as similar installation that all run into identical intrinsic problem, and be used for the needs of in update cycle distribution pulse-width signal.
For briefly, a preferred embodiment that shows among Fig. 3 demonstrates the embodiment that drives single LED1 with a pulse-width signal 6.
Please refer to Fig. 3, will describe this device with reference to the distribution pulse-width signal of independent 8 projects that representative data 2 is provided.Though be referred to 8 bit digital data this device is described, only because of 8 bit digital data suitable standard in industry.Can make a change and this change takes place really it.
In this embodiment, the invention provides the signal generator 7 of a plurality of pulse signals 8 of output.Each pulse signal 8 can be provided at the whole section multiple distribution of pulses in the time with the one or more combinations in other pulse signals 8.
As showing among Fig. 3, data 2 can be determined the mixing of signal of the correct representative data 2 of those needs with these other pulse signal 8 combinations.The pulse signal 6 of these accumulating forms offers LED1 then.
Provide the signal generator 7 of a plurality of signals to manage to provide the signal that can make up easily, so that the multiple scope of the various gradients that need represent numerical data to be provided.Moreover, wish that signal can be combined, make and compare that pulse provides the time durations of the multiple number percent that is covered by pulse with time durations without any pulse.They are combined increases the amplitude of individual pulses.Therefore, a plurality of pulse signals 8 comprise such pulse signal ideally, and any individual pulses of any signal is compared with other signal pulses that can make up with it, and described pulse can cover discrete time interval.Any specified moment in this time interval, a pulse can only be provided by in a plurality of pulse signals 8.
The present invention manages to implement the present invention with a logical circuit, and described logical circuit is used for producing these pulses and as signal generator 7.Circuit in this preferred embodiment comprises clock 5, counter 4, priority encoder 9 and demoder 10.
If adopt the example that shows in the preferred embodiment of 8 bit digital data 2, then these data can comprise any 256 unique binary bit numbers representing decade number from 0 to 255.
Though not strict needs, this preferred embodiment utilize a clock 5 and one 8 digit counters 4, make the time durations " T " of coupling update cycle can be separated into a plurality of less time intervals.Use 8 digit counters 4 that " T " during update time is separated into 256 less time intervals, each less time interval is by the continuous binary bit output expression of counter 4.
It should be noted that similar to the known technology that Fig. 1 discusses, the number of the time interval that the update cycle is separated into need not to mate gradient number possible in the numerical data.Comprise that at this in numerical data example of 8 signals, this preferred versions is mated this data with one 8 digit counters 4, with complete process data and clear the explanation.Yet counter 4 can be greater number, for example, 10 digit counters of increase is arranged on the position for other purposes.
Perhaps, the less position signal of use as 6 signals is possibility also, though this will reduce possible combination and insufficient utilization can be from all gradients of 8 position digital signals acquisition.
Please refer to signal generator 7, will recognize that counter 4 produces 256 numerical value binary bit signals in time durations " T ".On counter 4, be appointed as Q
0To Q
7Each 8 carry-out bit be mapped to input position on the priority encoder 9.
It is inferior that priority encoder manages to determine to send into binary digit purpose level.Highest significant position in the general identification of priority encoder 8 bit patterns.
In order to produce a plurality of output signals 8 of hope, will be appreciated that better signal comprises that the signal of the pulse with each second of containing 256 time intervals, another signal, each the 8th time interval that each the 4th time interval has pulse have another signal of pulse or the like, and wherein pulse does not overlap each other.The active occurrence frequency in position of these pulsed frequencies and counter 4 is complementary.Pulse signal comprises having and is being roughly 1/2
nT and n=1,2,3 ... Deng during in pulse signal.It is inferior that maximum n will mate the binary bit level in All Time interval.In this example, 256 time intervals are 2
8, so sequence stops when n=8.
If consider to map directly to the counter 4 of priority encoder 9, will recognize that then the signal distributions that is relevant to highest significant position is distributed in the time deficiently.For example, carry-out bit Q
7Be the highest significant position of 50% time durations, be the highest significant position of half number of producing by counter 4.Yet, it is the highest significant position of last 50% number that produces, and consider this be produce at signal, may originating of will causing a pulse signal, though it is represented during the pot life of half, but concentrate in last 50% the time durations, and in not being distributed in during the All Time.
Contrast ground, the present invention recognizes that the distribution of pulses of not hope is to be produced by highest significant position, and produce by the least significant bit (LSB) from counter 4.
On 256 unique binary bit numbers that produce from counter 4, Q
0The position will be 256 least significant bit (LSB)s on the binary digit purpose per second.Contrast ground, carry-out bit Q
7It is the least significant bit (LSB) of binary bit number " 10000000 ".This just takes place separately.
Use the method, priority encoder 9 is connected to counter 4, does not discern highest significant position, but actual identification is from the least significant bit (LSB) of counter 4.By reversing the mapping of output between line and input position, make counter 4 to be a position Q
0Minimum carry-out bit be mapped to the highest input position I of priority encoder 9
7, just can accomplish.As shown in the line 11 that shows among Fig. 3.
Output from priority encoder 9 comprises 256 continuous binary bit numbers, and each all represents from 0 to 7 decimal number purpose 3 bits number of pointing out the highest significant position discerned for the input of priority encoder 9.3 bits number can be transferred to demoder 10 by line 12 continuously.
10 signal comprises generally with sequence along line 12 to demoder: 7,6,7,5,7,6,7,4,7 ... the number sequence of form.
When demoder 10 is represented the input signal of decade number 7 in reception, at output P
7Last output one pulse.Similarly, receiving an input of representing decade number 4 will be at output P
4Last generation one pulse or the like.
In the output of priority encoder 9, the occurrence frequency of decade number 7 all has generation for it at the per second of 256 discrete outputs.Therefore at output P
7On demoder 10 be output as the per second pulse of 256 indivedual time slices.
Simplification form in the output of possible embodiment shown in Fig. 4 and Fig. 5.
Please refer to Fig. 4, the representativeness output of 3 systems is shown.Use same procedure, will comprise that from the output of the demoder of 3 generators wherein per second pulse produces the pulse signal P of a pulse
2, wherein per the 4th time interval produces the signal P of a pulse
1And comprise the signal P of individual pulse
0These can as hope be combined and represent 8 discrete signals by number 0 to 7 expression.Note that number represents by getting rid of all pulses.
Please refer to Fig. 5, representation signal P is shown
2And P
0The accumulation output of combination.This provides five pulses that are distributed in time durations " T ".
In these embodiments, note that pulse is not the complete time durations " T " that is distributed in equably for all combinations.As showing among Fig. 5, five individual pulses are distributed as single pulse, three pulse body, and another single pulse.When working with numerical data, the pulse that during 8 discrete less time intervals of " T " during whole section, produces and imperfect even distribution, unless less time interval " T " but beginning and end point self asynchronization.
Though it is this causes the undesirable distribution on 3 signals, when bits number increases, less as the whole structure that the distribution of three continuous impulse combined sequence showing among Fig. 5 produces.
Please get back to 8 embodiment that show among Fig. 3, can see the setting by AND door 14, data 2 can be combined with each signal in a plurality of signals 8.
O from data 2
7Position and P from demoder 10
7Signal plus.As the aforementioned, P
7Signal is included in per second place 128 individual pulses regularly of less time interval.At O
7The appearance of " 1 " and its combination by the AND door cause P on the data bit
7The output 16 of signal.Remainder data position O
0To O
6All be zero, and they by the AND door respectively with P
0To P
6On signal combination will suppress all the other pulse signals from AND door 14 output.As a result, the output 6 that is fed to LED1 is just from the P of demoder 10
7Output.
If being binary representations of numerical value 129, data 2 then can consider another example, on binary bit, and will be from the output of impact damper 15 at O
7Producing one " 1 " on the position reaches at O
0One " 1 " on the position.Therefore, from the AND passage downstream, from the P that has only of demoder 10 outputs
7And P
0Still exist, every other pulse signal is suppressed.This two signal makes up by OR door 17, makes output 6 comprise some 129 pulses.This is pulse signal P
7Additional pulse addition in the mid point that will produce one three continuous impulse in the middle of time durations obtains.This overcomes flash effect as described above near evenly distributing fully.
Therefore can see the invention provides and to produce the method and apparatus that the various energy levels that will be fed to display device 1 are represented in a series of pulses that are distributed in the time durations.Enforcement of the present invention need not to utilize the expensive Eprom of question blank or memory body address paragraph, but utilizes logical circuit.
Logical circuit utilizes the occurrence frequency of the lowermost level time position of counter to produce confession and send into the desired signal that the data subsequent combination is used.
Further aspect of the present invention can become clear to those people who knows this technology when reading description.The description relevant with preferred embodiment is not considered to limit the present invention, and a preferred embodiment and application of the present invention just are described.
The specific integer of mentioning in the entire chapter explanation can be replaced by functional equivalent when needed.
Claims (16)
1. one kind drives the method for digital indicator by distribution pulse-width signal in whole period, and this method comprises the following steps:
In time durations " T ", produce a plurality of pulse signals;
Each described a plurality of pulse signal provides at least one individual pulses in this time durations " T ";
With respect to any other pulse in any of described a plurality of pulse signals, each pulse of described a plurality of pulse signals during produce in the discrete time interval in " T "; And
Make up described pulse signal according to data, comprise the output signal of distribution pulse with generation, the part of the time durations " T " of data is sent in the summation representative of described distribution pulse.
2. method according to claim 1, the number of wherein said a plurality of pulse signals equal to represent the described data number of the binary digit of high number.
3. method according to claim 1, wherein said a plurality of pulse signals comprise containing and are being roughly 1/2 of time durations " T "
nPulse signal in the T time, and n=1,2,3 ... Deng, and maximum n equal during the number level time of " T " discrete time interval of being subdivided into.
4. method according to claim 1 wherein comprises the combination of described pulse signal and data and utilizes described data to select described pulse signal, then the synthetic single trial signal of selected sets of signals.
5. method according to claim 1 is wherein mated significance bit and the pulse signal sent in the binary bit value with the selection composite signal, and is carried out described selection.
6. one kind drives the device of digital indicator by distribution pulse-width signal in whole period, and this device comprises:
-at least one signal generator produces a plurality of pulse signals, and wherein each described signal comprises that individual pulses distributes, and provides each described individual pulses in the discrete time durations with respect to the individual pulses of all pulse signals in " T " during whole;
-AND coupling arrangement, will send into the position and described a plurality of pulse signals combinations of data-signal, represent this to send into data-signal so which to select in the described pulse signal should be combined; And
-OR coupling arrangement synthesizes the distribution pulse of representing this single series of sending into data to described a plurality of selected sets of signals in time durations " T ".
7. device according to claim 6, wherein said a plurality of pulse signals comprise that this sends into the pulse signal of each binary digit of data-signal.
8. device according to claim 6, wherein said a plurality of pulse signals comprise containing and are being roughly 1/2 of time durations " T "
nThe signal of the pulse in the T, and n=1,2,3 ... Deng, equal up to n till the binary bit level time of the discrete time interval number that " T " is subdivided into during whole section.
9. device according to claim 6, wherein said signal generator comprises: the clock actuation counter is used for producing a sequence binary bit number of designated duration " T " segmentation; Scrambler is used for discerning the least significant bit (LSB) of this counter and produces a sequence signal, and each signal is relative with each time interval, and the identification least significant bit (LSB); And demoder, be used in the discrete output of each independent least significant bit (LSB), producing the output pulse, and in the identical output of each common least significant bit (LSB) of being discerned, produce succeeding impulse.
10. one kind by producing the method that the discrete pulse signal of a plurality of times that is fit to do subsequent combination drives digital indicator, and this method comprises the following steps:
-produce the continuous binary bit number of wishing the time durations segmentation;
The inferior sequence number of exporting of the level of the continuous binary digit purpose least significant bit (LSB) that-identification is produced, each number is relative with single time durations segmentation, and identification lowermost level time position; And
Produce the output pulse on-in a plurality of outputs capable of being combined one, and produce the individual pulses of the time interval of each segmentation, and in common output, produce by time position pulse that recognizer produced of common lowermost level.
11. method according to claim 10, wherein said output pulse produces in the uniqueness output of each unique lowermost level of being discerned time position.
12. a device that drives digital indicator, by produce a plurality of pulse signals capable of being combined in whole period, this device comprises:
-counter produces a sequence binary bit number time durations is segmented;
-lowermost level time position recognizer is identified in the least significant bit (LSB) from the binary bit sequence of this counter output, and output represents the continuous signal of this least significant bit (LSB), and each sort signal is should timing separation relative with each; And
-pulse generator is used to activate the pulse in the discrete output of each unique lowermost level of being discerned time position, and activates the continuous impulse of the common lowermost level time position that will produce in common output.
13. device according to claim 12, wherein said lowermost level time position recognizer comprises the priority encoder that is connected in this counter, makes highest input of this scrambler be connected to the lowermost level time output of this counter.
14. device according to claim 13, wherein said pulse generator comprise the demoder that is used for receiving from the signal of described priority encoder.
Produce described binary bit number sequence 15. device according to claim 12, wherein said counter are driven, and utilize clock that described time durations is segmented.
16. device according to claim 12, wherein said a plurality of signals capable of being combined comprise n signal, and wherein the n representative is inferior from the binary bit number level of the time interval number of described counter.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US53552800A | 2000-03-27 | 2000-03-27 | |
| US09/535,528 | 2000-03-27 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1421028A true CN1421028A (en) | 2003-05-28 |
| CN1272757C CN1272757C (en) | 2006-08-30 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB01807359XA Expired - Lifetime CN1272757C (en) | 2000-03-27 | 2001-03-26 | Method and apparatus for driving digital display by distributing PWM pulses over time |
Country Status (12)
| Country | Link |
|---|---|
| EP (1) | EP1269455B1 (en) |
| JP (1) | JP2003529100A (en) |
| KR (1) | KR20020093011A (en) |
| CN (1) | CN1272757C (en) |
| AT (1) | ATE534984T1 (en) |
| AU (1) | AU779338B2 (en) |
| CA (1) | CA2403939C (en) |
| EA (1) | EA005964B1 (en) |
| HK (1) | HK1052789B (en) |
| MY (1) | MY126157A (en) |
| TW (1) | TW581999B (en) |
| WO (1) | WO2001073736A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100369078C (en) * | 2003-12-10 | 2008-02-13 | 精工爱普生株式会社 | PWM signal generation circuit and display driver |
| CN112985325A (en) * | 2021-04-21 | 2021-06-18 | 天津飞旋科技股份有限公司 | Position decoding method and device of sine and cosine encoder and computer readable medium |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3923341B2 (en) | 2002-03-06 | 2007-05-30 | 株式会社半導体エネルギー研究所 | Semiconductor integrated circuit and driving method thereof |
| GB2403841B (en) * | 2003-07-07 | 2006-08-09 | Pelikon Ltd | Control of Electroluminescent displays |
| KR100718962B1 (en) * | 2004-12-28 | 2007-05-16 | 엘지전자 주식회사 | Projection Display Driving Apparatus |
| WO2012022235A1 (en) * | 2010-08-19 | 2012-02-23 | 深圳市明微电子股份有限公司 | Method and device for frequency multiplication of display control |
| CN111033603B (en) * | 2017-05-08 | 2023-05-30 | 斯纳普公司 | Driving technique for modulation device |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03246592A (en) | 1990-02-23 | 1991-11-01 | Seiko Instr Inc | Gradation display circuit of display device |
| JP3500899B2 (en) | 1997-03-27 | 2004-02-23 | 三菱電機株式会社 | Image display method and image display device |
-
2001
- 2001-03-26 CA CA2403939A patent/CA2403939C/en not_active Expired - Lifetime
- 2001-03-26 AT AT01915598T patent/ATE534984T1/en active
- 2001-03-26 CN CNB01807359XA patent/CN1272757C/en not_active Expired - Lifetime
- 2001-03-26 WO PCT/IB2001/000477 patent/WO2001073736A1/en active IP Right Grant
- 2001-03-26 EA EA200201021A patent/EA005964B1/en not_active IP Right Cessation
- 2001-03-26 EP EP01915598A patent/EP1269455B1/en not_active Expired - Lifetime
- 2001-03-26 KR KR1020027012890A patent/KR20020093011A/en not_active Application Discontinuation
- 2001-03-26 AU AU42680/01A patent/AU779338B2/en not_active Ceased
- 2001-03-26 JP JP2001571376A patent/JP2003529100A/en active Pending
- 2001-03-27 MY MYPI20011399A patent/MY126157A/en unknown
- 2001-03-27 TW TW090107242A patent/TW581999B/en not_active IP Right Cessation
-
2003
- 2003-07-02 HK HK03104704.6A patent/HK1052789B/en not_active IP Right Cessation
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100369078C (en) * | 2003-12-10 | 2008-02-13 | 精工爱普生株式会社 | PWM signal generation circuit and display driver |
| CN112985325A (en) * | 2021-04-21 | 2021-06-18 | 天津飞旋科技股份有限公司 | Position decoding method and device of sine and cosine encoder and computer readable medium |
| CN112985325B (en) * | 2021-04-21 | 2021-08-17 | 天津飞旋科技股份有限公司 | Position decoding method and device of sine and cosine encoder and computer readable medium |
Also Published As
| Publication number | Publication date |
|---|---|
| EP1269455A1 (en) | 2003-01-02 |
| TW581999B (en) | 2004-04-01 |
| CA2403939A1 (en) | 2001-10-04 |
| EA200201021A1 (en) | 2003-02-27 |
| ATE534984T1 (en) | 2011-12-15 |
| HK1052789A1 (en) | 2003-09-26 |
| CA2403939C (en) | 2012-03-27 |
| KR20020093011A (en) | 2002-12-12 |
| HK1052789B (en) | 2012-03-09 |
| AU4268001A (en) | 2001-10-08 |
| EP1269455B1 (en) | 2011-11-23 |
| MY126157A (en) | 2006-09-29 |
| JP2003529100A (en) | 2003-09-30 |
| AU779338B2 (en) | 2005-01-20 |
| WO2001073736A1 (en) | 2001-10-04 |
| EA005964B1 (en) | 2005-08-25 |
| CN1272757C (en) | 2006-08-30 |
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